No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Effect of implant cleaning on titanium particle dissolution and cytocompatibility
Abstract
Background:
Peri-implantitis treatments are mainly based on protocols for teeth but have not shown favorable outcomes for implants. The potential role of titanium dissolution products in peri-implantitis necessitate the consideration of material properties in devising treatment protocols. We assessed implant cleaning interventions on 1) bacterial removal from titanium-bound biofilms, 2) titanium surface alterations and related titanium particle dissolution, and 3) cytocompatibility.
Methods:
Acid-etched titanium discs were inoculated with human peri-implant plaque biofilms and mechanical antimicrobial interventions were applied on the titanium-bound biofilms for 30 seconds each: 1) Rotary nylon brush; 2) Titanium brush; 3) Water-jet on high and 4) low, and compared to sterile, untreated and Chlorhexidine-treated controls. We assessed CFU counts, biofilm removal, surface changes via SEM and AFM, and titanium dissolution via light microscopy and ICP-MS. Biological effects of titanium particles and surfaces changes were assessed using NIH/3T3 fibroblasts and MG-63 osteoblastic cell lines, respectively.
Results:
Sequencing revealed that the human biofilm model supported a diverse biofilm including known peri-implant pathogens. Water-jet and Nylon brush were most effective in reducing CFU counts (p<0.01 vs. control), while Chlorhexidine was least effective; biofilm imaging results were confirmatory. Titanium brushes led to visible streaks on the treated surfaces, reduced corrosion resistance and increased titanium dissolution over 30 days of material aging as compared to controls, which increase was amplified in the presence of bacteria (all p-val<0.05). Titanium particles exerted cytotoxic effects against fibroblasts, while surfaces altered by titanium brushes exhibited reduced osteoconductivity versus controls (p<.05).
Conclusions:
Present findings support that mechanical treatment strategies selected for implant biofilm removal may lead to titanium dissolution. Titanium dissolution should become an important consideration in the clinical selection of peri-implantitis treatments and a necessary criterion for the regulatory approval of instruments for implant hygiene. This article is protected by copyright. All rights reserved.
... Next, a four-species model consisting of commensal S. oralis and V. parvula and pathogens F. nucleatum and P. gingivalis was utilized to evaluate any selective bactericidal effects of the mouthwash against each species in nascent, adherent biofilm. Subsequently, an established ex vivo oral biofilm model (26,27) was employed to assess the anti-biofilm effects of the naturopathic mouthwash as compared to commercially available mouthwashes for translational impact. This ex vivo model has been previously validated and includes over 80 different taxa of oral commensal and pathogenic bacteria, including taxa challenging to retain in culture such as Treponema (26,27). ...
... Subsequently, an established ex vivo oral biofilm model (26,27) was employed to assess the anti-biofilm effects of the naturopathic mouthwash as compared to commercially available mouthwashes for translational impact. This ex vivo model has been previously validated and includes over 80 different taxa of oral commensal and pathogenic bacteria, including taxa challenging to retain in culture such as Treponema (26,27). Lastly, a translational 3D spheroid fibroblast culture was used to demonstrate the impact of oral rinse treatment on host soft tissue cytocompatibility. ...
... Additionally, this study incorporated a clinically isolated multispecies sample of periodontitis, comprising a diverse range of over thirty bacterial genera to enhance clinical relevance and explore the extent of antibiofilm effects, including fastidious anaerobes like Porphoromonas, Bacteroides, and Tannerella and other periodontal pathogens like Fusobacterium, Prevotella, and Campylobacter (Supplementary Table S1). Detailed isolation, composition, retention of bacterial diversity, and culture methods for the ex vivo ecological biofilm have been previously described (26,27). ...
Introduction
Oral rinses intended for the prevention and treatment of periodontal diseases have traditionally focused on bactericidal effects. This study evaluates the efficacy of a naturopathic mouthwash containing plant attenuations and propolis against common gram- pathogenic and gram+ commensal oral species in comparison to conventional antiseptic oral rinses.
Methods
Streptoccoccus oralis, Streptococcus gordonii, Veillonella parvula, Fusobacterium nucleatum, and Porphyromonas gingivalis were cultured and treated with naturopathic StellaLife® VEGA® Oral Rinse (SL), 0.12% chlorhexidine gluconate (CHX), LISTERINE® COOL MINT® mouthwash (LIS), or phosphate-buffered saline (PBS) as negative control. Firstly, planktonic bacterial growth was assessed through optical density measurements and colony-forming unit (CFU) counts. Subsequently, a 4-species or clinical ex vivo multispecies biofilm was used to evaluate antibiofilm effects through selective agar plating and fluorescence in situ hybridization (FISH) or live-dead biofilm imaging, respectively. Lastly, cytocompatibility to oral rinses was tested using a 3D human fibroblast spheroid model.
Results
SL significantly inhibited the growth of disease-associated F. nucleatum and P. gingivalis 12 and 120 h, respectively, after treatment, while exhibiting lower toxicity toward commensal S. oralis, S. gordonii , and V. parvula vs. LIS or CHX (all p < 0.05). Correspondingly, in 4-species biofilms, selective agar plating and FISH-staining showed decreased abundance of F. nucleatum and P. gingivalis after 4 h recovery following SL treatment vs. PBS control while maintaining a robust commensal biofilm of S. oralis and V. parvula . In contrast, CHX or LIS treatment demonstrated non-selective killing, leading to sparse biofilms with residual F. nucleatum and P. gingivalis . When tested against clinical ex vivo multispecies biofilms, all oral rinses showed significant antibiofilm effects (all p < 0.001), disrupting biofilm structure and reducing bacterial viability. Lastly, 3D human fibroblast spheroids treated with CHX or LIS displayed greater cytotoxicity with detachment of cellular debris from the spheroid mass, while spheroids exposed to SL exhibited minimal cell death with cellular viability maintained across the spheroid structure.
Discussion
The SL homeopathic rinse demonstrated selective action on oral bacteria, preferentially reducing pathogen bacterial load while preserving commensal species with high cytocompatibility. Future validation in human studies is needed to assess its selective antimicrobial activity to maintain a eubiotic oral microbiome and explore broader applications in oral health.
... While these methods have been shown to be effective in removing both soft and hard deposits [40,41], their use is not without complications [42]. As observed in various studies-including in vitro research, animal studies, and clinical trials in humans-the use of these instruments may contribute to the release of titanium particles into the surrounding environment [43,44], leading to implant surface damage specifically related to the implant passivation layer, iatrogenic implant corrosion [45] and increased osteoclastic activity [43]. Unlike these methods, which are considered contact abrasive approaches [44,46], other non-abrasive methods have shown lower titanium release from the implant surface. ...
... As observed in various studies-including in vitro research, animal studies, and clinical trials in humans-the use of these instruments may contribute to the release of titanium particles into the surrounding environment [43,44], leading to implant surface damage specifically related to the implant passivation layer, iatrogenic implant corrosion [45] and increased osteoclastic activity [43]. Unlike these methods, which are considered contact abrasive approaches [44,46], other non-abrasive methods have shown lower titanium release from the implant surface. Indeed, in clinical studies, these non-abrasive treatments [45,47] have demonstrated better results, particularly in terms of probing depths reduction [45]. ...
... However, evidence regarding surface alterations and potential titanium particle release following its use remains limited and scarce. Therefore, peri-implantitis research should focus on identifying implant surface decontamination strategies that effectively eliminate biofilms while preserving the electrochemical properties of titanium [44]. This approach is essential to prevent accelerated titanium dissolution in peri-implant tissues and to maintain the biocompatibility of titanium implants. ...
Aim
To evaluate the clinical and radiographic outcomes of non‐surgical treatment followed by either reconstructive therapy or supportive care with no further surgical measures for the treatment of peri‐implantitis intra‐bony defects.
Materials and Methods
This randomized clinical trial included patients diagnosed with peri‐implantitis exhibiting intrabony defects (≥ 3 mm). All 36 patients received a standardized peri‐implant non‐surgical therapy. Patients who did not demonstrate disease resolution based on clinical and radiographic re‐evaluation were randomized into two groups. The test group received reconstructive therapy [reconstructive group (RG)] while the control group received no additional treatment except supportive care every 3 months [non‐reconstructive group (NRG)]. The primary outcome was the mean radiographic bone change at 12 months; the difference between groups was assessed using Mann–Whitney two‐sample tests. Clinical and radiographic parameters were recorded at the initial examination and at 3, 6, and 12 months. Also, patient‐reported outcomes were assessed.
Results
Overall, 34 patients (implants = 34) completed the study. Both therapies resulted in significant clinical and radiographic changes after 12 months. Disease resolution was achieved in 8 (44.4%) NRG patients and 7 (43.8%) RG patients ( p ≥ 0.05) with no significant differences between groups. The groups displayed no significant differences in clinical variables, but radiographic bone fill was ~3× greater in the RG group at 12 months [1.21 (SD 0.92) mm versus 0.36 (SD 0.59) mm], demonstrating statistical significance between the tested groups.
Conclusions
The tested therapeutic modalities demonstrated equal disease resolution. Nevertheless, the marginal bone level gain was significantly greater for sites subjected to reconstructive surgical therapy ( NCT05168891 —This clinical trial was not registered prior to participant recruitment and randomization).
... Additionally, it has been recognized that once the integrity of the passivation film is destroyed, if it cannot be repaired immediately, titanium will no longer be immune to corrosion and could be vulnerable in corrosive environments 10 . Specifically, titanium particles resulting from implant corrosion and degradation have been linked to severe cytotoxicity and pro-inflammatory cellular responses 11,12 . ...
... Information on the growth of the multispecies clinical biofilm is provided in the supplemental information as previously described 16 . Biofilm samples retained multiple oral taxa, with an enrichment of gram-negative taxa known to be prevalent in peri-implantitis, such as S. sanguinis, V. parvula, and Neisseria species 11 . Subsequently, the samples were treated by different clinical decontamination treatments to simulate dental implant cleaning interventions that are common in practice 17 . ...
... Next, we analyzed whether the damaged oxide film could be repassivated in biological conditions by aging for 31 days in simulated inflammatory conditions using a previously established electrolytic solution rich in proteins under anaerobic conditions 11 . These conditions simulate the inflammatory environmental conditions in peri-implantitis disease. ...
Motivated by clinical problems of titanium implant degradation, we developed a workflow that enabled assessment of surface oxide dynamics as a function of clinical interventions and inflammation conditions. We found that mechanical damage led to decrease of stoichiometric TiO2 ratio in the passivation oxide film and further resulted in accelerated degradation under inflammatory anaerobic conditions. This method can be employed for the assessment of surface oxides to monitor implant safety.
... As discussed previously in this article, no biomaterial is fully bioinert. However, select non-toxic biomaterials such as titanium can achieve a homeostatic state within the peri-implant tissues enabling a long-term functional stability (108). This state is dynamic and contingent upon the biomaterial's capacity to reach an electrochemical equilibrium, while present in biological fluids. ...
... In the context of implant biomaterial-host equilibrium, successful osseointegration is characterized by a controlled immune/ inflammatory response that is critical to peri-implant wound healing and, in most cases, resolves timely to allow chronic immune surveillance to aid in maintaining tissues homeostasis. Nonetheless, if the tissue environment is not conducive to the electrochemical stability of the titanium passivation layer, destructive corrosion can occur leading to titanium dissolution from the implant surfaces (107,108). Wennerberg et al. (117) addressed the extent of primary corrosion during the osseointegration of titanium implants with various surface modifications by artificial material aging in solution for 1month at atmospheric conditions. None of the implant surfaces exhibited dissolution of titanium from the surface during the experiment in buffered saline suggesting that an electrochemical equilibrium is rapidly established and sustained under favorable conditions, which resemble healthy tissue, i.e. oxygen availability, neutral pH=7.3 (117). ...
... When the chronic electrochemical oxidation of titanium leads to gradual destruction of the passivation layer, the effects of corrosion are not limited to the biomaterial but also affect osteoimmune regulation of osseointegration. This has been evidenced by two recent studies (108,121) from independent research groups showing that abrasive dental treatments, such as ultrasonic instrumentation with steel instruments used to clean the implants surface, leads to destructive corrosion. This can be regarded as secondary corrosion when compared to the primary oxidation, i.e. corrosion, which occurs during healing of implants and has a protective effect in most cases via the formation of the passivation layer. ...
In the field of biomaterials, an endosseous implant is now recognized as an osteoimmunomodulatory but not bioinert biomaterial. Scientific advances in bone cell biology and in immunology have revealed a close relationship between the bone and immune systems resulting in a field of science called osteoimmunology. These discoveries have allowed for a novel interpretation of osseointegration as representing an osteoimmune reaction rather than a classic bone healing response, in which the activation state of macrophages ((M1–M2 polarization) appears to play a critical role. Through this viewpoint, the immune system is responsible for isolating the implant biomaterial foreign body by forming bone around the oral implant effectively shielding off the implant from the host bone system, i.e. osseointegration becomes a continuous and dynamic host defense reaction. At the same time, this has led to the proposal of a new model of osseointegration, the foreign body equilibrium (FBE). In addition, as an oral wound, the soft tissues are involved with all their innate immune characteristics. When implant integration is viewed as an osteoimmune reaction, this has implications for how marginal bone is regulated. For example, while bacteria are constitutive components of the soft tissue sulcus, if the inflammatory front and immune reaction is at some distance from the marginal bone, an equilibrium is established. If however, this inflammation approaches the marginal bone, an immune osteoclastic reaction occurs and marginal bone is removed. A number of clinical scenarios can be envisioned whereby the osteoimmune equilibrium is disturbed and marginal bone loss occurs, such as complications of aseptic nature and the synergistic activation of pro-inflammatory pathways (implant/wear debris, DAMPs, and PAMPs). Understanding that an implant is a foreign body and that the host reacts osteoimmunologically to shield off the implant allows for a distinction to be drawn between osteoimmunological conditions and peri-implant bone loss. This review will examine dental implant placement as an osteoimmune reaction and its implications for marginal bone loss.
... Air polishing with glycine powder demonstrated good antimicrobial efficacy (88.5% bacterial reduction) with moderate surface alterations. These results are consistent with those reported by Schwarz et al., who found that air polishing with glycine powder effectively removed biofilm from various implant surfaces with minimal abrasive effects 16 [16][17][18][19][20] . These findings suggest that while chlorhexidine may be beneficial as an adjunct to mechanical debridement, alternative decontamination approaches might be more suitable for the comprehensive treatment of peri-implantitis. ...
... Air polishing with glycine powder demonstrated good antimicrobial efficacy (88.5% bacterial reduction) with moderate surface alterations. These results are consistent with those reported by Schwarz et al., who found that air polishing with glycine powder effectively removed biofilm from various implant surfaces with minimal abrasive effects 16 [16][17][18][19][20] . These findings suggest that while chlorhexidine may be beneficial as an adjunct to mechanical debridement, alternative decontamination approaches might be more suitable for the comprehensive treatment of peri-implantitis. ...
Background: Dental implants for replacing missing teeth has become standard practice in dentistry. Biological complications like peri-implantitis is common and involves biofilm-induced inflammation and bone loss around implants. Material and Methods: Sixty standardized titanium discs (10 mm diameter, 2 mm thickness) were fabricated from grade 4 commercially pure titanium. All discs underwent sandblasting and acid etching to create a surface topography representative of contemporary dental implants. Surface characterization was performed using scanning electron microscopy (SEM) to ensure standardization across specimens. The discs were sterilized by gamma irradiation prior to biofilm formation. Results: Er:YAG laser and photodynamic therapy achieved the highest bacterial reductions (94.3% and 92.1%).However, Er:YAG laser treatment also caused noticeable surface alterations, including melting and re- solidification patterns and smoothing of some surface irregularities. Conclusion: Photodynamic therapy caused minimal surface alteration compared to other modalities. It may offer the best balance between antimicrobial efficacy and surface preservation in peri-implantitis management.
... The effects of cleaning the surfaces of Ti implants were studied by Kotsakis et al., who found that the mechanical treatment of Ti implants may increase the dissolution of Ti in peri-implant tissues, potentially contributing to the development of peri-implantitis. 68 Their results were supported by an ex vivo model of organic polymicrobial peri-implant biofilms, which was more representative of clinical conditions than other single-or three-species biofilm models. 68 The findings were also biologically relevant, as the tests regarded the crucial cell types involved in the homeostasis of peri-implant tissues. ...
... 68 Their results were supported by an ex vivo model of organic polymicrobial peri-implant biofilms, which was more representative of clinical conditions than other single-or three-species biofilm models. 68 The findings were also biologically relevant, as the tests regarded the crucial cell types involved in the homeostasis of peri-implant tissues. 69 Furthermore, the study showed that Ti was detectable in peri-implant crevicular fluid (PICF) and gingival crevicular fluid (GCF), even in healthy subjects. ...
This paper presents the major achievements in the field of biomaterials in restorative dentistry and tissue regeneration reported over the past 3 years. The review aims to summarize the knowledge on important biomaterials and the emerging modification strategies to improve their biointegration, biological activity, mechanical properties, and resistance to the harsh oral environment. We also discuss the main opportunities and challenges associated with the use of biomaterials in dentistry.
Much contemporary research focuses on the interactions between biomaterials and the surrounding tissues in the oral environment regarding adhesion, associated stresses and strains, and the durability of dental restoration materials. Dental biomaterials should support cell adhesion and activity, leading to dental tissue regeneration, and are also expected to effectively prevent bacterial infections and inhibit material corrosion in saliva. The degradation, dissolution or corrosion of restorative materials due to exposure to body fluids can alter the structure and mechanical properties of the material, causing various adverse effects.
Another aspect addressed in recent literature is the improvement of the mechanical properties and esthetics of restorative materials. The surfaces of biomaterials are usually modified with polymers or nanomaterials to reduce friction while maintaining biocompatibility.
Although all modern biomaterials are promising, there is an urgent need for more in vivo and clinical studies to investigate their biological advantages and disadvantages in detail. The computational techniques used to assess the properties of modern dental materials, particularly the mechanical ones, could assist in the development of the materials. Such an approach can help bring new biomaterials to the market by reducing complicated, tedious and expensive experimentation.
... ere were 26 in-vitro studies [8-27, 29, 30, 32, 33, 35, 39], 3 ex-vivo studies [5,28,38], 3 observational in-vivo studies [31,34,36], 1 case-control study [37], and 1 case report [40]. Eighteen studies reported the factors responsible for biotribocorrosion [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25], while 16 reported the toxic effects of the released metal ions [5,[26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. e review results are summarized as follows: ...
... erefore, the Ti ions increased the sensitivity of gingival epithelial cells to microorganisms and promoted monocyte infiltration in the oral cavity leading to cytotoxicity and inflammation at the implant-gingival tissue interface [27]. e 1 to10 µm diameter Ti ions released from the dental implant biofilm removal were cytotoxic to fibroblasts [39]. A comparative evaluation of cytotoxic effects of CpTi and its alloy Ti6Al4V on human gingival fibroblast showed better cell viability with CpTi. ...
Bio-tribocorrosion is a phenomenon that combines the essentials of tribology (friction, wear, and lubrication) and corrosion with microbiological processes. Lately, it has gained attention in implant dentistry because dental implants are exposed to wear, friction, and biofilm formation in the corrosive oral environment. They may degrade upon exposure to various microbial, biochemical, and electrochemical factors in the oral cavity. The mechanical movement of the implant components produces friction and wear that facilitates the release of metal ions, promoting adverse oro-systemic reactions. This review describes the bio-tribocorrosion of the titanium (Ti) dental implants in the oral cavity and its toxicological implications. The original research related to the bio-tribo or tribocorrosion of the dental implants was searched in electronic databases like Medline (Pubmed), Embase, Scopus, and Web of Science. About 34 studies included in the review showed that factors like the type of Ti, oral biofilm, acidic pH, fluorides, and micromovements during mastication promote bio-tribocorrosion of the Ti dental implants. Among the various grades of Ti, grade V, i.e., Ti6Al4V alloy, is most susceptible to tribocorrosion. Oral pathogens like Streptococcus mutans and Porphyromonas gingivalis produce acids and lipopolysaccharides (LPS) that cause pitting corrosion and degrade the TiO2. The low pH and high fluoride concentration in saliva hinder passive film formation and promote metal corrosion. The released metal ions promote inflammatory reactions and bone destruction in the surrounding tissues resulting in peri-implantitis, allergies, and hyper-sensitivity reactions. However, further validation of the role of bio-tribocorrosion on the durability of the Ti dental implants and Ti toxicity is warranted through clinical trials.
... A broad categorisation of implant surface decontamination approaches divides them into chemical, mechanical or combination interventions 277 . With regard to biofilm removal efficacy, chemical reagents generally have much higher antibiofilm efficacy compared to mechanical interventions such as ultrasonics and curettes designed for use around teeth 276 , or even abrasion-driven implant cleaning aids such as titanium brushes. Nevertheless, in addition to having limited biofilm removal capacity, mechanical instrumentation of the surface leads to a long-term release of titanium biomaterial degradation products in the form of particles. ...
... Nevertheless, the use of chemical antimicrobial agents poses risks to the cytocompatibility of the implant surface. It has been shown that chemotherapeutic agents invariably adsorb on the implant surface and, depending on their molecular composition, may prevent cellular reattachment on the treated surface 276 . CHX is a prime example because this organic macromolecule is adsorbed on the implant surface, where it demonstrates substantivity and protracted cytotoxicity against osteoblastic cells 282 . ...
Peri-implantitis is an infectious disease that leads to progressive bone loss. Surgical therapy has been advocated as a way of halting its progression and re-establishing peri-implant health. One of the most challenging but crucial tasks in the management of peri-implantitis is biofilm removal to achieve reosseointegration and promote the reduction of peri-implant pockets. A wide variety of strategies have been used for implant surface decontamination. Mechanical means have been demonstrated to be effective in eliminating calculus deposits and residual debris; however, the presence of undercuts and the grooves and porosities along the roughened implant surface make it difficult to achieve an aseptic surface. In conjunction with mechanical measures, use of chemical adjuncts has been advocated to dilute bacterial concentrations, destroy the bacteria's organic components and eliminate endotoxins. Pharmacological adjuncts have also been recommended to diminish the bacterial load. Other strategies, such as use of lasers, implantoplasty and electrolysis, have been suggested for implant surface decontamination to promote predictable clinical and radiographic outcomes.
... Os discos de titânio foram fixados, com o auxílio de anteparo plástico esterilizado, na tampa da placa. Fechando a placa com a tampa contendo os discos, estes ficaram submersos no inóculo e então foram incubados em condição de aerobiose a 37 °C por 24 horas 15,16 . ...
... Devido à característica da técnica de EDS, que é apenas de análise de elementos químicos, não é possível afirmar que foi gerada uma fase cristalina de óxido de titânio (TiO 2 ) após a aplicação do agente descontaminante. Estudos mostram que a ocorrência da formação de TiO 2 é importante, podendo inclusive influenciar na desestabilização molecular bacteriana 12,16 . ...
Introdução
Tratamentos têm sido propostos para a peri-implantite com o objetivo de descontaminar a superfície dos implantes, removendo microrganismos que podem estar associados à doença.
Objetivo
O objetivo deste estudo foi avaliar a ação in vitro de diferentes métodos de aplicação de digluconato de clorexidina (CLX) na descontaminação de discos de titânio (Ti) com microtopografia e seu efeito físico-químico sobre a superfície.
Material e método
Vinte discos de Ti foram expostos a inóculo de Escherichia coli por 24 horas. Foram distribuídos em quatro grupos de descontaminação (n=5): 1 - um minuto de exposição à solução de CLX 0,12%; 2 - dois minutos de exposição à solução de CLX 0,12%; 3 - esfregaço durante um minuto com gel de CLX 1%; 4 - esfregaço durante um minuto com gel de CLX 2%. O produto de cada disco foi diluído e plaqueado individualmente. Após 24 horas, realizou-se contagem das unidades de colônias formadas (UFC).
Resultado
O grupo com o menor número de crescimento de UFC foi o grupo 4 (0,20±0,37), com apenas UFC em uma das amostras. Seguido do grupo 2 (0,40±0,73), grupo 1 (18,60±33,96). O grupo 3 apresentou as maiores quantidades de UFC (36,07±41,39). Em todas as amostras, foi possível observar uma diminuição estatisticamente significante da concentração superficial de Ti, assim como um aumento de Oxigênio.
Conclusão
Pode-se concluir que o uso de CLX gel a 2% em superfícies de Ti com microtopografia contaminadas com E. coli propicia a eliminação das UFC e que sua aplicação resulta em diminuição do percentual de Ti e aumento do teor de O.
... As reported by others, these findings underscore the importance of considering the specific cleaning method and surface conditions when managing protein contamination on titanium implants. [68][69][70] Future research on polymeric nanoparticles (NPs) for dental implant decontamination should take a comprehensive approach, focusing on immediate cleaning efficacy and long-term impacts on implant integrity, patient health, and the environment. Optimising NP formulations, such as adjusting size, shape, and surface properties, is critical to enhancing biofilm removal. ...
Peri-implant diseases, such as peri-implantitis, affect up to 47% of dental implant recipients, primarily due to biofilm formation. Current decontamination methods vary in efficacy, prompting interest in polymeric nanoparticles (NPs) for their antimicrobial and protein-specific cleaning properties. This study evaluated the efficacy of polymeric nanoparticles (NPs) in decontaminating titanium dental implants by removing proteinaceous pellicle layers and resisting recontamination. Titanium discs were treated with saline water, PrefGel®, hydrogen peroxide (H2O2), GUM® Paroex®, or polymeric NPs, and analysed using SEM, EDX, XPS, and contact angle measurements to assess changes in surface composition, morphology, and hydrophilicity. Polymeric NPs significantly reduced nitrogen levels compared to PrefGel® (mean reduction: 2.6%, p < 0.05), indicating effective protein removal. However, their carbon reduction efficacy was similar to that of other agents. SEM images revealed that polymeric NPs disaggregated larger protein aggregates but did not fully decontaminate the surface. Contact angle analysis showed changes in hydrophilicity consistent with other treatments. Hydrogen peroxide performed best overall, achieving the lowest carbon levels post-recontamination (mean reduction: 13%, p < 0.01). While polymeric NPs exhibited unique protein-specific cleaning potential, their overall performance was comparable to traditional agents. Residual contaminants, including carbon and oxygen, persisted on all treated surfaces, indicating enhanced cleaning strategies were needed. These findings highlight the potential of polymeric NPs as an innovative approach to implant decontamination, particularly for protein-specific biofilm control. However, their efficacy in broader applications remains like that of conventional methods. This research contributes to developing targeted decontamination protocols to manage peri-implant diseases and improve long-term implant outcomes.
... Regarding the decontamination of the dental implant with peri-implantitis, most authors recommend the use of "radical" therapies, that is, treatments that are very aggressive for the surface of the dental implant, such as implantoplasty or Ti brushes. Kotsakis et al. [123] compared different methods of decontamination such as Ti brush, Nylon, and a pressurized water system, and determined the corrosion resistance and dissolution of Ti. The results of this interesting study highlight that more aggressive mechanical decontamination methods modify the surface of the dental implant, affecting the osteoconductive properties of the material. ...
Dental implantology has transformed modern dentistry, providing long-lasting solutions for patients with various types of edentulism. However, the increased use of dental implants has led to more complications. Peri-implantitis, an inflammatory disease affecting tissues around implants, causes bone loss and can lead to implant failure if untreated. The shift from mechanical to treated (roughened) implant surfaces has improved osseointegration but complicated decontamination. Various methods, such as sprays, electrolysis, and techniques like titanium brushes or implantoplasty, have been proposed to address these challenges. Implantoplasty, which involves smoothing and polishing the implant surface to remove bacterial biofilm and reduce roughness, is effective in treating peri-implantitis. However, it generates metallic particles that could adversely affect peri-implant tissues and systemic health. This chapter evaluates the biosafety of implantoplasty, examining the physicochemical characteristics of released metal particles, their impact on cellular health, the inflammatory and osteogenic response, and systemic effects observed in animal model studies.
... Ti is a metallic element common for different uses in dentistry [13]. Ti sterilization may affect its mechanical properties depending on the sterilization method and the number of cycles, possible results are Ti dissolution, change in retention force values, surface morphology, roughness, hydrophobicity, etc. [14]. Burkhardt et al. found that contamination of Ti-base abutments followed by cleaning (different protocols were tested) can degrade the bonding properties to titanium and only the protocol with alcohol after contamination showed bond failure (in thermo-mechanical aging tests) and hence lower retention force value [15]. ...
Background
The purpose of this pilot in-vitro study was to assess the effect of sterilization on the intra-implant axis, inter-implant axis, intra-implant distance and inter-implant distance of three implants in a straight line by using laboratory scanner (LBS) versus intra-oral scanner (IOS) with intra-oral scan bodies (ISB). Methods: A printed 3D model with three internal hex analogs in the positions 15#,16#,17# was used. Zirkonzhan (ZZ) intra-oral scan body (ISB), two-piece titanium was used. The ZZ ISBs were scanned by 7 Series dental wings (LBS) and 30 times by Primescan (IOS) pre sterilization and 30 times post sterilization. For each scan (pre and post) stereolithography (STL) file was created and a comparison between all the scans pre sterilization and post sterilization were superimposed on the laboratory scan by using a 3D analyzing software. A Kolmogorov-Smirnov test performed followed by Wilcoxon Signed Ranks tests. (p < 0.05) Results: Post sterilization of the ZZ ISB, the mean errors were significantly increased for the inter-implant distances (p < 0.0005), intra-implant distances 1,2,3 (p < 0.0005), intra-implant axis 1,3 (p < 0.0005) and inter-implant axes 13,23 (p < 0.05). In contrast, the mean errors for intra-implant axis 2 (p < 0.0005) and inter-implant axis 12 (p < 0.0005) were significantly reduced. Conclusions: ZZ ISB showed changes in all four parameters after sterilization. The middle ISB had the largest changes in mean error regarding all four parameters. Sterilization process may affect the three-dimensional (3D) structure of the ZZ ISB after three cycles. There is a lack in the literature in this field and there is a need for further studies to explore the effect of sterilization (multiple cycles) on different ISBs and for creating an approved guidelines regarding the amount of sterilization for each ISB in the industry.
... The Ti implants released substantially more and larger particles than the Zr discs, except for the ZM discs treated with diamond burs. This finding is consistent with a previous study suggesting that Zr implants release fewer particles than Ti-implants [34,35]. But the implantoplasty-induced release of implant particles may cause a reduction in both diameter and thickness of the implant, leading to a diminished fracture resistance [36]. ...
This study investigates the impact of various instrumentation techniques on material removal and surface changes in titanium (Ti)- and zirconia (Zr) implant discs. Ti- and Zr discs were subjected to standardized experiments using various instruments including airflow, ultrasound, carbide, and diamond burs. Instrumentation was performed for 60 s with continuous automatic motion. Abrasion and changes in surface roughness were assessed using profilometry, while scanning electron microscopy was used to examine morphological changes and particle size. Carbide burs predominantly caused abrasion on Ti discs, while diamond burs caused more abrasion on Zr discs. The Ti discs were more susceptible to surface changes. However, among the materials tested, machined Zr discs treated with diamond burs produced the largest particle. In certain cases, a statistical significance (p < 0.05) was observed between the groups, while in others, there was no considerable difference among the means (p > 0.05). These results highlighted the statistical significance of our findings. These results found diverse alterations in surface characteristics of Ti- and Zr discs due to different instruments, with carbide and diamond burs causing notable effects. The findings highlight the need for a careful balance between promoting healing and minimizing harm during implantoplasty.
... Titanium implants are generally corrosion-resistant; however, in certain conditions, corrosion can occur [15][16][17][18][19][20]. Exposure to possibly corrosive substances, such as toothpastes [21,22], acidic mouthwashes, or other cleaning methods [23], as well as to an increased bacterial load, [19,[24][25][26] may lead to titanium corrosion and in turn may influence the biofilm composition and tissue damage. ...
Preclinical and clinical research on two-piece zirconia implants are warranted. Therefore, we evaluated the in vitro fracture resistance of such a zirconia oral implant system. The present study comprised 32 two-piece zirconia implants and abutments attached to the implants using a titanium (n = 16) or a zirconia abutment screw (n = 16). Both groups were subdivided (n = 8): group T-0 comprised implants with a titanium abutment screw and no artificial loading; group T-HL was the titanium screw group exposed to hydro-thermomechanical loading in a chewing simulator; group Z-0 was the zirconia abutment screw group with no artificial loading; and group Z-HL comprised the zirconia screw group with hydro-thermomechanical loading. Groups T-HL and Z-HL were loaded with 98 N and aged in 85 °C hot water for 10⁷ chewing cycles. All samples were loaded to fracture. Kruskal–Wallis tests were executed to assess the loading/bending moment group differences. The significance level was established at a probability of 0.05. During the artificial loading, there was a single occurrence of an implant fracture. The mean fracture resistances measured in a universal testing machine were 749 N for group T-0, 828 N for group Z-0, 652 N for group T-HL, and 826 N for group Z-HL. The corresponding bending moments were as follows: group T-0, 411 Ncm; group Z-0, 452 Ncm; group T-HL, 356 Ncm; and group Z-HL, 456 Ncm. There were no statistically significant differences found between the experimental groups. Therefore, the conclusion was that loading and aging did not diminish the fracture resistance of the evaluated implant system.
... Titanium (Ti) is a metallic element common for different uses in dentistry [31]. Ti sterilization may affect its mechanical properties depending on the sterilization method and the number of cycles, possible results are Ti dissolution, change in retention force values, surface morphology, roughness, hydrophobicity, etc. [32]. Burkhardt et al found that contamination of Ti-base abutments followed by cleaning (different protocols were tested) can degrade the bonding properties to titanium and only the protocol with alcohol after contamination showed bond failure (in thermo-mechanical aging tests) and hence lower retention force value [33]. ...
Background: The purpose of this pilot in-vitro study was to assess the effect of sterilization on the intra-implant axis, intra-implant distance, inter-implant distance and inter-implant axis of three implants in a straight line by using laboratory scanner (LBS) versus intra-oral scanner (IOS) with intra-oral scan bodies (ISB).
Methods: A printed 3D model with three internal hex analogs in the positions 15#,16#,17# was used. Zirkonzhan (ZZ) intra-oral scan body (ISB), two-piece titanium was used. The ZZ ISBs were scanned by 7 Series dental wings (LBS) and 30 times by Primescan (IOS) pre sterilization and 30 times post sterilization. For each scan (pre and post) stereolithography (STL) file was created and a comparison between all the scans pre sterilization and post sterilization were superimposed on the laboratory scan by using a 3D analyzing software. A Kolmogorov-Smirnov test performed followed by Wilcoxon Signed Ranks tests. (p <0.05)
Results: Poststerilization of the ZZ ISB, the mean errors were significantly increased for the inter-implant distances (p <0.0005), intra-implant distances 1,2,3 (p <0.0005), intra-implant axis 1,3 (p <0.0005) and inter-implant axes 13,23 (p <0.05). In contrast, the mean errors for intra-implant axis 2 (p <0.0005) and inter-implant axis 12 (p <0.0005) were significantly reduced.
Conclusions: ZZ ISB showed changes in all four parameters after sterilization. The middle ISB had the largest changes in mean error regarding all four parameters. Sterilization process may affect the three-dimensional (3D) structure of the ZZ ISB after three cycles. There is a lack in the literature in this field and there is a need for further studies to explore the effect of sterilization (multiple cycles) on ISB and for creating an approved guidelines regarding the amount of sterilization for each ISB in the industry.
... While debris from the implant itself may be released to the peri-implant bone, such debris may also be produced at the interface between the prosthesis and the implant or between the implant and the transmucosal abutments [13]. In fact, numerous studies have found titanium particles released from the implants in the surrounding tissues [14][15][16][17][18][19][20][21]. Within this debate, the activation of NLRP3, specifically, may help in finding a biologically plausible explanation for the differences between periodontitis and peri-implantitis. ...
The activation of inflammasomes is thought to induce the inflammatory process around dental implants. No information is available on the correlation between microbiota and inflammasomes in clinical samples from patients suffering peri-implantitis. For this cross-sectional study, 30 biofilm samples were obtained from 19 patients undergoing surgical treatment for peri-implantitis because of the presence of bleeding on probing, probing depth higher than 6 mm, and radiographic bone loss higher than 3 mm. Then, soft tissue samples from around the implant were also collected. The relative abundance of bacteria and alpha-diversity indexes were calculated after analyzing the 16S rRNA gene using next-generation sequencing. The soft-tissue samples were processed for evaluation of the inflammasomes NLRP3 and AIM2 as well as caspase-1 and IL-1β. The relative abundance (mean (SD)) of specific species indicated that the most abundant species were Porphyromonas gingivalis (10.95 (14.17)%), Fusobacterium vincentii (10.93 (13.18)%), Porphyromonas endodontalis (5.89 (7.23)%), Prevotella oris (3.88 (4.94)%), Treponema denticola (2.91 (3.19)%), and Tannerella forsythia (2.84 (4.15)%). Several correlations were found between the species and the immunohistochemical detection of the inflammasomes NLRP3 and AIM2 as well as caspase-1 and IL-1β, both in the epithelium and the lamina propria. A network analysis found an important cluster of variables formed by NLRP3 in the lamina propria and AIM2, caspase-1, and IL-1β in the lamina propria and the epithelium with Prevotella dentalis, Prevotella tannerae, Tannerella forsythia, or Selenomonas timonae. Thus, it could be concluded that inflammasomes NLRP3 and AIM2 and their downstream effectors caspase-1 and interleukin-1β can be significantly associated with specific bacteria.
... 26 Detailed isolation and culture methods for the ex vivo ecological bio lm have been previously described. 26,27 Assessment of Oral Rinsing Treatment on Planktonic Bacterial Growth ...
Background
The growing utilization of oral rinses in dental and periodontal care has prompted the need for innovative products with selective antibacterial properties. This study evaluates the efficacy of an herbal compound rinse (StellaLife VEGA Oral Rinse, StellaLife Inc, IL) containing plant attenuations and propolis, in comparison to conventional antimicrobial oral rinses.
Materials and Methods
Streptoccoccus oralis, Streptococcus gordonii DL1, Veillonella parvula, Fusobacterium nucleatum, and Porphyromonas gingivalis were cultured and treated with StellaLife VEGA Oral Rinse (SL), 0.12% chlorhexidine (CHX), and Listerine Cool Mint mouthwash. Planktonic bacterial growth was assessed through optical density measurements (OD600), and colony forming units (CFU) counts. A clinical ex vivo multi-species biofilm was used to evaluate antibiofilm effects through fluorescence biofilm tracking.
Results
SL significantly inhibited the growth of F. nucleatum 12 hours after treatment and P. gingivalis 96 hours after treatment, while exhibiting lower toxicity toward commensal bacteria such as S. oralis, S. gordonii, and V. parvula compared to LIS or CHX. In the clinical ex vivo biofilm, StellaLife, CHX, and Listerine all showed significant antibiofilm effects, disrupting biofilm structure and reducing bacteria viability.
Conclusions
SL’s selective action on oral bacteria, targeting pathogens while preserving commensal microbes, holds promise for selective preservation of eubiotic biofilms. This study demonstrates the potential of this herbal compound rinse as an effective aid to selectively combat particularly against periodontal pathogens. Additional clinical studies are warranted to validate these findings and explore their broader applications in oral health.
... Дана гіпотеза може бути інкорпорована в структуру уже попередньо проаналізованих результатів імплантопластики по відношенню до шансу подальшого виживання уражених імплантатів: в ході клінічного дослідження було встановлено, що незважаючи на факт проведення модифікації поверхні імплантату, ураженого периімплантитом, прогноз виживання таких критично не змінювався, а основними предикторами можливих змін були вихідні характеристики ураження (рівень втрати оточуючої кісткової тканини) [38]. У експериментальному дослідженні Kotsakis G.A. та колег (2021) вдалось відмітити, що механічна очистка поверхонь титанових дентальних імплантатів з використанням титанових щіточок провокує зниження корозієстійкості інтраосальних опор та асоційована із зростанням розчинності титану на протязі 30 днів (останній феномен також набирав прогресуючого тренду при наявності бактеріальної контамінації) [39]. ...
Вступ. Корозія дентальних імплантатів, як процес поступової деградації сплавів титану, що використовуються в якості основного матеріалу для їх виготовлення, є мультифакторним за своєю етіологією та відбувається під дією електричних, хімічних та механічних чинників, і характеризується впливом на стан пери-імплантантних тканин та структуру мікробіому периімплантатної ділянки. Мета дослідження. Систематизувати дані щодо феноменів корозії дентальних титанових імплантатів та вивільнення іонів з поверхні встановлених інтраосальних опор у розрізі їх клінічної значущості з урахуванням причин виникнення. Матеріали та методи. Дослідження було проведено у форматі ретроспективного огляду літератури. З метою пошуку публікацій, які в найбільшій мірі були релевантними з поставленою метою дослідження, та які потенційно могли містити інформацію щодо причин розвитку та клінічної значимості феномену корозії дентальних титанових імплантатів, був сформований наступний набір ключових слів: «dental implant», «corrosion», «titanium dissolution», «ion release». Опрацювання відібраних наукових робіт передбачало проведення деталізованого контент-аналізу у відповідності до попередньо сформованих категорій. Результати дослідження та їх обговорення. Виходячи з дефіциту доступних клінічних даних належної якості важко резюмувати, чи корозія дентальних імплантатів може провокувати прогресування уже наявної патології периімплантиту, чи є причинним фактором по відношенню до розвитку запальних змін в оточуючих тканинах. Взаємозв’язки між розвитком периімплантиту та дефектами оксидної плівки на поверхні титану досі остаточно не вивчені, однак в попередніх дослідженнях було відмічено, що корозія дентального імплантату потенційно може розцінюватися, як один із тригерних факторів для розвитку периімплантиту, а імплантати з ознаками запалення оточуючої кісткової тканини характеризуються наявністю дефектів оксидної плівки. Попри те, що достатньо якісних доказів щодо зв’язку концентрації наявних частинок титану в оточуючих тканинах з ризиком розвитку периімплантитного запалення досі не виявлено, доступні дані свідчать, що частинки титану в принципі можуть відігравати прозапальну роль по відношенню до змін стану периімплантаційних тканин. Висновки. Питання клінічної значимості фактору мікророзчинності поверхонь титанових дентальних імплантатів та їх корозії залишається предметом дискусії, однак враховуючи дефіцит доказів, які б підтверджували визначальну, або ж ініціативну роль корозії у розвитку периімплантатних порушень можна зробити висновок, що повільна деградація титанових поверхонь в ході функціонування внутрішньокісткових опор не становить загрози для прогнозу успішності та виживання останніх, а також не характеризується вираженим негативним впливом на організм пацієнта за умов відсутності суміжних запальних змін у формі перимукозиту чи периімплантиту.
... These findings are of utmost importance as healthy implants could present with titanium corrosion. In contrast, compromised implants are frequently decontaminated with physical or chemical methods that have been shown to produce surface alterations and disseminate titanium particles into the surrounding tissues (Kotsakis et al., 2021;Romanos et al., 2021). ...
Peri-implantitis is an inflammatory condition induced by bacterial biofilm that affects the soft and hard tissues surrounding dental implants, compromising the success of implant therapy. Recent studies have highlighted the potential links between peri-implant health and systemic inflammation, including uncontrolled diabetes mellitus, psychological stress, cardiovascular disease, obesity, and infectious diseases such as COVID-19. As an inflammatory disease, peri-implantitis may trigger systemic inflammation by elevating circulating levels of pro-inflammatory cytokines, which could have unknown impacts on overall health. While the relationship between periodontal health and systemic conditions is better understood, the association between peri-implant disease and systemic inflammation remains unclear. Therefore, this comprehensive review aims to summarize the most recent evidence on the relationship between peri-implantitis and systemic inflammation, focusing on biological complications, microbiology, and biomarkers. This review aims to enhance our understanding of the links between peri-implantitis and systemic inflammation and promote further research in this field by discussing the latest insights and clinical implications.
... 16 Above all, one of the most common routes of Ti particle release may be through hygiene instrumentation during maintenance appointments as shown in vitro, and conversely, it has been demonstrated that the use of nylon brushes to clean Ti releases fewer Ti particles. 27 Eger et al. showed that millions of Ti particles were produced by an ultrasonic metal tip used to clean dental implants, and these particles in turn induced osteoclastic bone resorption in mice. 28 Other studies have also evaluated the results of non-surgical treatment for peri-implant disease using abrasive dental instruments and have reported minimal improvement especially with a diagnosis of peri-implantitis. ...
Background:
Peri-implantitis is a frequent finding. Initial treatment involves non-surgical debridement of the implant surface. Recent studies have found a correlation between titanium particle release and peri-implantitis, yet there is a dearth of information regarding the effect of various non-surgical instrumentation on particle release or peri-implantitis resolution.
Materials and methods:
Patients with peri-implantitis were recruited for a randomized, blinded, parallel-group clinical trial. The implants were randomized to treatment composed of titanium curettes (group "Mech") or implant-specific treatment composed of rotary polymer microbrushes (group "Imp"). Titanium (Ti) release in submucosal peri-implant plaque pre- and 8 weeks post-treatment was assessed as the primary outcome. Peri-implant probing depth, bleeding on probing, and suppuration on probing were evaluated and compared between groups.
Results:
34 participants completed treatment; 18 were randomized to the Mech group and 16 to the Imp group. The groups were comparable for Ti levels and probing depths at baseline. A trend was noted for 10-fold greater Ti dissolution in the Mech group post-treatment compared to the Imp group (P = 0.069). The Imp group had a significant reduction in probing depth post-treatment (p = 0.006), while the Mech group reduction was not significant.
Conclusion:
Peri-implantitis treated non-surgically with implant-specific instruments had a significantly greater decrease in probing depth versus the Mech treatment group. This improvement was linked with a trend for less titanium release to the peri-implant plaque by the non-abrasive treatment. This article is protected by copyright. All rights reserved.
... However, it has been found that the mechanical treatment strategies used to remove implant biofilms may cause titanium dissolution and increase the cytotoxicity. Therefore, the dissolution of implant material should be an important consideration in the clinical choice of treatment of peri-implant inflammation [137]. ...
Biofilms are aggregates formed as a protective survival state by microorganisms to adapt to the environment and can be resistant to antimicrobial agents and host immune responses due to chemical or physical diffusion barriers, modified nutrient environments, suppression of the growth rate within biofilms, and the genetic adaptation of cells within biofilms. With the widespread use of medical devices, medical device-associated biofilms continue to pose a serious threat to human health, and these biofilms have become the most important source of nosocomial infections. However, traditional antimicrobial agents cannot completely eliminate medical device-associated biofilms. New strategies for the treatment of these biofilms and targeting biofilm infections are urgently required. Several novel approaches have been developed and identified as effective and promising treatments. In this review, we briefly summarize the challenges associated with the treatment of medical device-associated biofilm infections and highlight the latest promising approaches aimed at preventing or eradicating these biofilms.
... Modifications of the implant microstructure are undesirable because they can reduce corrosion resistance and be cytotoxic to fibroblasts. This was shown before as a less powerful WaterJet showed minor biofilm removal compared to a nylon brush but better-preserved titanium surface structure and corrosion resistance [42]. ...
Peri-implantitis-associated inflammation can lead to bone loss and implant failure. Current decontamination measures are ineffective due to the implants’ complex geometry and rough surfaces providing niches for microbial biofilms. A modified water jet system (WaterJet) was combined with cold plasma technology (CAP) to achieve superior antimicrobial efficacy compared to cotton gauze treatment. Seven-day-old multi-species-contaminated titanium discs and implants were investigated as model systems. The efficacy of decontamination on implants was determined by rolling the implants over agar and determining colony-forming units supported by scanning electron microscopy image quantification of implant surface features. The inflammatory consequences of mono and combination treatments were investigated with peripheral blood mononuclear cell surface marker expression and chemokine and cytokine release profiles on titanium discs. In addition, titanium discs were assayed using fluorescence microscopy. Cotton gauze was inferior to WaterJet treatment according to all types of analysis. In combination with the antimicrobial effect of CAP, decontamination was improved accordingly. Mono and CAP-combined treatment on titanium surfaces alone did not unleash inflammation. Simultaneously, chemokine and cytokine release was dramatically reduced in samples that had benefited from additional antimicrobial effects through CAP. The combined treatment with WaterJet and CAP potently removed biofilm and disinfected rough titanium implant surfaces. At the same time, non-favorable rendering of the surface structure or its pro-inflammatory potential through CAP was not observed.
... 43 Future wellcontrolled studies are needed to explore further the effect of laser treatment on implant surfaces and the healing potential of the surgical sites, as material dissolution could be cytotoxic to fibroblasts and affect osteoconductivity. 44 ...
Background:
Lasers represent a promising method for implant decontamination, but evidence on implant surface changes and subsequent biofilm formation is limited. This study aimed to assess the effect of Er:YAG laser treatment on zirconia and titanium discs, and the differences in biofilm formation as a result of surface alterations.
Methods:
A two-stage (in vitro and in vivo) experiment utilizing Er:YAG laser on titanium and zirconia discs was performed. In vitro, surface alterations, roughness, and elemental-material weight differences following laser treatment were assessed using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). In vivo, four participants wore custom-made intra-oral stents, embedded with laser-treated and untreated titanium and zirconia discs overnight. Biofilm-coated discs were stained using nucleic acid fluorescence dye and visualized using multiphoton confocal laser scanning microscopy. Biofilm 3D structure, biomass, thickness, and live-to-dead bacteria ratio were assessed.
Results:
Both titanium (TiZir) and zirconia (YTZP) discs treated with Er:YAG laser resulted in visual surface alterations, but showed no significant change in average surface roughness (titanium P = 0.53, zirconia P = 0.34) or elemental-material-weight (TiZir, P = 0.98), (YTZP, P = 0.96). No significant differences on biofilm biomass, average thickness and live-to-dead bacteria ratio of laser-treated titanium and zirconia discs, were identified compared to untreated groups (titanium P > 0.05, zirconia P >0.05). Generally, zirconia discs presented with a lower live-to-dead bacteria ratio compared to titanium discs, regardless of laser treatment.
Conclusion:
Er:YAG laser treatment of titanium and zirconia implant surfaces does not significantly affect surface roughness, elemental-material weight, and early biofilm formation in the oral cavity. This article is protected by copyright. All rights reserved.
... Likewise, the effects of the release of these metal ions and nanoparticles into the medium are still unknown. 5,13,14 On the other hand, the interaction between Ti metal particles and peri-implant tissues still raises controversy. 15 Albrektsson et al. 16 suggested that this metal debris triggers a foreign body reaction, while others 17,18 reported that Ti particles induce a pro-inflammatory response. ...
Background:
The objective of this study was to evaluate the accumulation of ions in blood and organs caused by Ti metal particles in a mandibular defect in rats, together with a description of the local reaction of oral tissues to these titanium alloy debris.
Methods:
Twenty Sprague-Dawley rats were randomly distributed into three groups: an experimental group with a mandibular bone defect filled with metallic debris obtained by implantoplasty; a positive control group; and a negative control group. Thirty days after surgery, the rats were euthanized and perilesional tissue surrounding the mandibular defect was removed, together with the lungs, spleen, liver and brain. Two blood samples were collected: immediately before surgery and before euthanasia. The perilesional tissue was histologically analyzed using hematoxylin-eosin staining, and titanium, aluminum and vanadium ion concentrations in blood and organs were measured by TQ-ICP-MS. Descriptive and bivariate analyses of the data were performed.
Results:
All rats with implanted metal debris showed metal particles and a bone fracture callus on the osseous defect. The metal particles were surrounded by a foreign body reaction characterized by the presence of histiocytes and multinucleated giant cells. The experimental group had a significant higher concentration of Ti ions in all studied organs except lung tissue (p < 0.05). In addition, there were more V ions in the brain in the experimental group (p = 0.008).
Conclusions:
Although further studies are required to confirm the clinical relevance of these results, Ti metal particles in the jaw might increase the concentration of metal ions in vital organs and induce a foreign body reaction. This article is protected by copyright. All rights reserved.
... Comparisons with other studies using only water jetting to decontaminate or clean implant surfaces are difficult, because not only the surface contamination-microbial or artificial-or surface models used, but also the physical properties (e.g. water pressure) of devices used were very different [24,[55][56][57]. ...
Background
Peri-implantitis therapy is a major problem in implantology. Because of challenging rough implant surface and implant geometry, microorganisms can hide and survive in implant microstructures and impede debridement. We developed a new water jet (WJ) device and a new cold atmospheric pressure plasma (CAP) device to overcome these problems and investigated aspects of efficacy in vitro and safety with the aim to create the prerequisites for a clinical pilot study with these medical devices.
Methods
We compared the efficiency of a single treatment with a WJ or curette and cotton swab (CC) without or with adjunctive use of CAP (WJ + CAP, CC + CAP) to remove biofilm in vitro from rough titanium discs. Treatment efficacy was evaluated by measuring turbidity up to 72 h for bacterial re-growth or spreading of osteoblast-like cells (MG-63) after 5 days with scanning electron microscopy. With respect to application safety, the WJ and CAP instruments were examined according to basic regulations for medical devices.
Results
After 96 h of incubation all WJ and CC treated disks were turbid but 67% of WJ + CAP and 46% CC + CAP treated specimens were still clear. The increase in turbidity after WJ treatment was delayed by about 20 h compared to CC treatment. In combination with CAP the cell coverage significantly increased to 82% (WJ + CAP) or 72% (CC + CAP), compared to single treatment 11% (WJ) or 10% (CC).
Conclusion
The newly developed water jet device effectively removes biofilm from rough titanium surfaces in vitro and, in combination with the new CAP device, biologically acceptable surfaces allow osteoblasts to grow. WJ in combination with CAP leads to cleaner surfaces than the usage of curette and cotton swabs with or without subsequent plasma treatment. Our next step will be a clinical pilot study with these new devices to assess the clinical healing process.
... TPs seemingly represent a common finding in peri-implant tissues that may originate from drilling, friction and instrumental manipulation during routine dental procedures (Kister et al., 2017;Kotsakis et al., 2020;Suárez-López Del Amo et al., 2018). ( Wilson et al., 2015). ...
Objectives:
To identify titanium particles (TPs) in biopsy specimens harvested from peri-implantitis lesions and secondarily to study the histopathological characteristics in peri-implantitis compared to periodontitis, in order to evaluate whether the presence of TPs could alter respective inflammatory patterns.
Material and methods:
Biopsies containing granulation tissue were harvested during routine surgical treatment in 39 peri-implantitis cases and 35 periodontitis controls. Serial sections were obtained using titanium-free microtome blades. The first and last sections of the peri-implantitis specimens were used for identification of TPs by scanning electron microscopy coupled with dispersive X-ray spectrometry. Intermediate sections and periodontitis specimens were processed for descriptive histological study using haematoxylin-eosin staining and for immunohistochemical analysis using CD68, IL-6, Nf-kB and VEGF markers.
Results:
TPs were identified in all peri-implantitis specimens as free metal bodies interspersed within granulation tissue. However, presence of macrophages or multinucleated giant cells engulfing the TPs were not identified in any specimen. Peri-implantitis granulations were characterized by a chronic inflammatory infiltrate rich in neutrophils. About half of peri-implantitis patients exhibited a subacute infiltrate characterized with lymphocytes interweaved with neutrophils and eosinophils. When compared to periodontitis, peri-implantitis tissues showed higher proportions of macrophages and a more intense neovascularization, based on significantly higher expression of CD68 and VEGF respectively.
Conclusion:
TPs were identified in all peri-implantitis specimens, but without evidencing any foreign body reaction suggestive for direct pathological effects of TPs. The peri-implantitis granulation tissue was characterized by intense neovascularization and presence of a chronic inflammatory infiltrate dominated by plasma cells, neutrophils and macrophages.
... Furthermore, a higher concentration of titanium is associated with the predominance of M1 macrophage polarization (Fretwurst et al., 2016). Titanium particles may be released into soft tissue during the implant placement, or as a result of electrochemical corrosion after the insertion, and accumulate over time (Abraham, Grenón, Sánchez, Pérez, & Valentinuzzi, 2006;Flatebø et al., 2006;Kotsakis et al., 2021). In addition, the release of acidic products by bacteria such as Streptococcus mutans and lipopolysaccharide from Gram-negative bacteria promotes the dissolution of titanium in the oral environment (Souza et al., 2013;Yu, Addison, Baker, & Davenport, 2015). ...
Objective
To conduct a systematic review of the inflammatory elements in peri-implantitis (PI) and peri-implant mucositis (PM) in comparison with healthy peri-implant tissues (HI) and periodontal disease.
Design
The PubMed, Embase, Web of Science, and Scopus databases were searched up to December 2020. English articles that evaluated human soft tissue biopsies of PI or PM were included. Values reported for the surface area of the infiltrated connective tissue (ICT) were pooled using the random-effect model meta-analysis to estimate the mean (95% CI).
Results
A total of 33 articles were included. Of 30 studies on PI, the majority evidenced significantly increased vascularization and inflammatory cell counts dominated by plasma cells in PI compared with HI. Studies that compared PI with chronic periodontitis primarily reported more severe inflammatory infiltrates in PI. This was confirmed by the meta-analysis results since the surface area of the ICT was significantly larger in PI (p<0.001). Only seven studies analyzed the PM lesions and reported increased inflammatory infiltrates and vascularization in PM compared with HI. Based on the meta-analysis results, the surface area of the ICT was 3.00 [1.50, 4.51] mm ² in PI and 0.23 [0.02, 0.44] mm ² in PM lesions. Based on the available evidence, presence of foreign body particles considerably increased the inflammatory infiltrate; however, smoking did not have a significant effect.
Conclusions
There was controversy regarding the prevalence of various inflammatory cell types in peri-implant diseases; however, a considerably high ICT surface area in PI indicates the aggressive nature of the disease.
... On one hand, detached titanium particles have been shown to have a significant direct effect on the inflammatory response, thereby inducing peri-implant osteolysis and macrophage response. [32][33][34] On the other hand, these particles favor a noxious shift in the adjacent biofilm [35]. Using soft tip materials, considerable amounts of debris were found on the rough implant surfaces. ...
Background
To assess the changes of implant surfaces of different roughness after instrumentation with ultrasonic-driven scaler tips of different materials.
Methods
Experiments were performed on two moderately rough surfaces (I—Inicell® and II—SLA®), one surface without pre-treatment (III) and one smooth machined surface (IV). Scaler tips made of steel (A), PEEK (B), titanium (C), carbon (D) and resin (E) were used for instrumentation with a standardized pressure of 100 g for ten seconds and under continuous automatic motion. Each combination of scaler tip and implant surface was performed three times on 8 titanium discs. After instrumentation roughness was assessed by profilometry, morphological changes were assessed by scanning electron microscopy, and element distribution on the utmost surface by energy dispersive X-ray spectroscopy.
Results
The surface roughness of discs I and II were significantly reduced by instrumentation with all tips except E. For disc III and IV roughness was enhanced by tip A and C and, only for IV, by tip D. Instrumentation with tips B, D and E left extensive residuals on surface I, II and III. The element analysis of these deposits proved consistent with the elemental composition of the respective tip materials.
Conclusion
All ultrasonic instruments led to microscopic alterations of all types of implants surfaces assessed in the present study. The least change of implant surfaces might result from resin or carbon tips on machined surfaces.
The peri-implant mucosal barrier is a unique microenvironment where host-microbiome interactions take place on the surface of an implanted biomaterial. Therefore, peri-implant immunity not only is quintessential to oral health but also contributes to the maintenance of the biomaterial-tissue equilibrium in health. This review delves into the intricate interplay between host factors, biomaterial properties, and the microbiome with a focus on the mechanisms underlying peri-implant dysbiosis. Investigations into this complex milieu have led to the emerging understanding of titanium particles released from the implant as significant exposomes. When biomaterial breakdown occurs, implant degradation products form particles that are released in the peri-implant crevice, exerting profound effects on the local immune surveillance. Comparative analyses with natural dentition highlight the distinct immune responses elicited by titanium particles, thereby implicating them as a key modulator of peri-implant dysbiosis that differentiates peri-implant from periodontal inflammation. Nonetheless, disruptions in the homeostatic balance of host-biomaterial interactions are linked to pathogenic shifts of the peri-implant microbiome that are correlated with titanium particles in humans. Collectively, it is now well established that to elucidate the mechanisms governing peri-implant dysbiosis, this triangle of host-microbiome-biomaterial has to be conjointly investigated. This review highlights findings from studies that have underscored the multifaceted nature of peri-implant dysbiosis, emphasizing the intricate crosstalk between host immunity, biomaterial characteristics, and microbial ecology. These findings suggest that the titanium particle exposome may alter key inflammatory cascades in the peri-implant tissues including toll-like receptor activation and inflammasome and complement signaling, which lead to nonresolving destructive inflammation. The presence of abiotic danger signals in the form of implant degradation products in peri-implant tissues may make antimicrobial monotherapies largely ineffective for managing peri-implantitis. In turn, the future of peri-implantitis therapy seems to lie in the development of targeted host modulatory interventions against titanium-mediated inflammatory pathways.
Background
This study compared titanium and zirconia implant ligature‐induced peri‐implant defect progression and response to regenerative surgical intervention.
Methods
Eight tissue‐level endosseous implants were placed in 6 mixed‐breed foxhounds, with 2 zirconia and 2 titanium alternating in each hemimandible. Cotton ligatures were placed subgingivally for 16 weeks followed by 8 weeks of spontaneous progression. Standardized radiographs were captured every 2 weeks to evaluate the rate of bone loss. Regenerative surgery was performed utilizing water‐jet decontamination, enamel matrix derivative, and locally harvested autogenous bone. After 16 weeks of healing, final radiographic bone levels as well as probing depths, recession, and clinical attachment levels were assessed.
Results
All 48 implants integrated successfully. The final average post‐ligature radiographic defects were 2.88 and 3.05 mm for titanium and zirconia implants, respectively. There was no significant difference between materials in the rate of radiographic bone loss ( p = 0.09). Following regenerative surgery, the total average amount of radiographic bone gain was 1.41 and 1.20 mm for titanium and zirconia, respectively. The percentage of defect fill was 51.56% and 37.98% ( p = 0.03) for titanium and zirconia, respectively. Inter‐group differences were minimal for clinical parameters at the time of sacrifice including periodontal pocket depths ( p = 0.81), recession ( p = 0.98), or clinical attachment levels ( p = 0.51).
Conclusions
No significant difference was found in the rate of peri‐implant defect development between titanium and zirconia implants. Both materials gained significant radiographic bone following regenerative surgery with significantly greater defect percentage fill in titanium implants. The final clinical parameters were similar in both groups.
Background
Implant surface decontamination is a critical step in peri‐implantitis treatment. The aim of this study was to assess the effect chemotherapeutic agents have on reosseointegration after treatment on ligature‐inducted peri‐implantitis.
Methods
Six male canines had 36 implants placed and ligatures were placed around them for 28 weeks to establish peri‐implantitis. The peri‐implant defects were randomly treated by 1 of 3 methods: 0.12% chlorhexidine (CHX test group), 1.5% sodium hypochlorite (NaOCl test group), or saline (Control group). Sites treated with NaOCl and CHX were grafted with autogenous bone, and all sites then either received a collagen membrane or not. Histology sections were obtained at 6 months postsurgery to assess percentage of reosseointegration.
Results
Thirty‐five implants were analyzed (CHX: 13; NaOCl: 14; Control:8). NaOCl‐treated sites demonstrated reosseointegration with direct bone‐to‐implant‐contact on the previously contaminated surfaces (42% mean reosseointegration), which was significantly higher than Controls ( p < 0.05). Correspondingly, clinical improvement was noted with a significant reduction in probing depth from 5.50 ± 1.24 mm at baseline to 4.46 ± 1.70 mm at 6‐months postsurgery ( p = 0.006). CHX‐treated sites demonstrated a nonsignificant reosseointegration of 26% ( p > 0.05); however, in the majority of cases, the new bone growth was at a distance from the implant surface without contact. Probing depths did not improve in the CHX group. The use of membrane did not influence reosseointegration or probing depths (all p > 0.05).
Conclusion
Titanium implants with peri‐implantitis have the capacity to reosseointegrate following regenerative surgery. However, treatment response is contingent upon the chemotherapeutic agent selection. Additional chemical treatment with 1.5% NaOCl lead to the most favorable results in terms of changes in defect depth and percentage of reosseointegration as compared to CHX, which may hinder reosseointegration.
Objectives
Self‐performed oral hygiene is essential for preventing dental caries, periodontal, and peri‐implant diseases. Oral irrigators are adjunctive oral home care aids that may benefit oral health. However, the effects of oral irrigation on oral health, its role in oral home care, and its mechanism of action are not fully understood. A comprehensive search of the literature revealed no existing broad scoping reviews on oral irrigators. Therefore, this study aimed to provide a comprehensive systematic review of the literature on oral irrigation devices and identify evidence gaps.
Methods
The Joanna Briggs Institute and Preferred Reporting Items for Systematic reviews and Meta‐Analyses extension for Scoping Reviews guidelines were utilized to prepare the review. Four databases and eight gray literature sources were searched for English publications across any geographical location or setting.
Results
Two hundred and seventy‐five sources were included, predominantly from scientific journals and academic settings. Most studies originated from North America. Research primarily involved adults, with limited studies in children and adolescents. Oral irrigation was safe and well‐accepted when used appropriately. It reduced periodontal inflammation, potentially by modulating the oral microbiota, but further research needs to clarify its mechanism of action. Promising results were reported in populations with dental implants and special needs. Patient acceptance appeared high, but standardized patient‐reported outcome measures were rarely used. Anti‐inflammatory benefits occurred consistently across populations and irrigant solutions. Plaque reduction findings were mixed, potentially reflecting differences in study designs and devices.
Conclusions
Oral irrigators reduce periodontal inflammation, but their impact on plaque removal remains unclear. Well‐designed, sufficiently powered trials of appropriate duration need to assess the clinical, microbiological, and inflammatory responses of the periodontium to oral irrigation, particularly those with periodontitis, dental implants, and special needs. Patient‐reported outcome measures, costs, caries prevention, and environmental impact of oral irrigation need to be compared to other oral hygiene aids.
Introduction: Titanium is considered to be an inert material owing to the ability of the material to form a passive titanium oxide layer. However, once the titanium oxide layer is lost, it can lead to exposure of the underlying titanium substructure and can undergo corrosion.
Summary: The article explores the role of titanium ions and particles from dental implants on cells, cytokine release, and on the systemic redistribution of these particles as well as theories proposed to elucidate the effects of these particles on peri-implant inflammation based on evidence from in-vitro, human, and animal studies. Titanium particles and ions have a pro-inflammatory and cytotoxic effect on cells and promote the release of pro-inflammatory mediators like cytokines. Three theories to explain etiopathogenesis have been proposed, one based on microbial dysbiosis, the second based on titanium particles and ions and the third based on a synergistic effect between microbiome and titanium particles on the host.
Conclusion: There is clear evidence from in-vitro and limited human and animal studies that titanium particles released from dental implants have a detrimental effect on cells directly and through the release of pro-inflammatory cytokines. Future clinical and translational studies are required to clarify the role of titanium particles and ions in peri-implant inflammation and the etiopathogenesis of peri-implantitis.
Objective
To assess which decontamination method(s) used for the debridement of titanium surfaces (disks and dental implants) contaminated with bacterial, most efficiently eliminate bacterial biofilms.
Material and Methods
A systematic search was conducted in four electronic databases between January 1, 2010 and October 31, 2022. The search strategy followed the PICOS format and included only in vitro studies completed on either dental implant or titanium disk samples. The assessed outcome variable consisted of the most effective method(s)—chemical or mechanical— removing bacterial biofilm from titanium surfaces. A meta‐analysis was conducted, and data was summarized through single‐ and multi‐level random effects model ( p < .05).
Results
The initial search resulted in 5260 articles after the removal of duplicates. After assessment by title, abstract, and full‐text review, a total of 13 articles met the inclusion criteria for this review. Different decontamination methods were assessed, including both mechanical and chemical, with the most common method across studies being chlorhexidine (CHX). Significant heterogeneity was noted across the included studies. The meta‐analyses only identified a significant difference in biofilm reduction when CHX treatment was compared against PBS. The remaining comparisons did not identify significant differences between the various decontamination methods.
Conclusions
The present results do not demonstrate that one method of decontamination is superior in eliminating bacterial biofilm from titanium disk and implant surfaces.
Surface decontamination is a crucial step in the treatment of peri‐implant infections, yet deep and mild cleansing techniques are lacking. Drawing inspiration from lysosomes, which enclose hydrolytic enzymes within their membranes to safely and effectively degrade organics within cells, the use of a near‐infrared (NIR)/H2O2‐activated TiO2‐x‐Alginate system for enclosed and deep surface decontamination is proposed. It leverages synergistically generated reactive oxygen species (ROS) to eliminate bacterial contaminants, mimicking the process of lysosomal digestion. By employing Ca²⁺ spray‐induced surface gelation, the TiO2‐x and H2O2 around implant surface are enclosed, creating a membrane‐like isolation. This system robustly degrades extracellular polymeric substances (EPS)‐mimic biomacromolecules, removes organic residues (OR) from both mono‐species (Staphylococcus aureus and Porphyromonas gingivalis) biofilm and polymicrobial ex vivo biofilm of peri‐implantitis, while avoiding healthy tissue irritation. Encouragingly, this system has also demonstrated powerful decontamination capabilities when applied to clinic‐retrieved infected dental implants. Notably, this technique restores the pristine implant surface topography and chemical composition, which are further revealed by the minimal inflammation response observed in macrophage culture and subcutaneous implantation. Consequently, osteoblast functionalities are effectively restored, and re‐osseointegration in vivo is also greatly enhanced. Thus, this deep decontamination strategy holds great promise for clinical applications in managing peri‐implant infections.
Objective:
Our aim was to examine the effect of titanium particles and lipopolysaccharide (LPS) from P. gingivalis on the inflammatory profile expression of human gingival fibroblasts (hGFs), cultured on rough titanium discs, in an in vitro peri-implantitis simulation.
Design:
Human gingival fibroblasts cultured on SLA and TCP surfaces were challenged with LPS, titanium particles or both. At 24, 48 and 72 h after treatment, MTT assay was performed to assess cell proliferation. FDA/PI staining was performed for the same time periods, in order to evaluate cell viability/apoptosis. At 5 and 7 days after the treatment, qPCR was performed to assess gene expressions of IL-6, IL-8 and COL1A1, as well as SEM on titanium discs.
Results:
All groups presented a significant increase of their population between the time periods of examination. Regarding the interleukin gene expression, the combination of LPS and particles significantly increased the levels of Interleukin-8. Treatment with LPS and particles also induced a significant increase of Interleukin-6 and collagen. FDA/PI microscopy has revealed several apoptotic cells in the treatment groups. SEM micrographs have shown the difficulty of hGFs to adhere on rough surfaces.
Conclusions:
The combination of titanium particles and LPS significantly upregulated the expression of IL-6, IL-8 and Col-1a. It appears that particles may arouse similar reactions to the endotoxin, while synergistically intensifying it.
The study aims: 1. To perform diode laser, titanium (Ti) brush, and Ti curette treatment on sandblasted and acid-etched (SLA) Ti surfaces, with/without H2O2 and CHX, 2. To investigate the influence of decontamination techniques on implant surface topography and hydrophilicity. Diode laser, Ti brush, and Ti curette treatments were performed on the Grade 4 Ti discs, with/without treatment with 3% H2O2 solution or 0.2% CHX. Surface characteristics were investigated via SEM, optical profilometry, and water contact angle meter. SEM findings revealed flat and scratched areas when treated with Ti curette and Ti brush. For diode laser, SEM showed melting in specific areas. Ra and Rt values were lower in all test groups than in the control group (p < 0.05). The adjunctive chemical treatment showed negligible effects in SEM images and surface roughness measurements compared to laser and mechanical treatment-only groups. H2O2 treatment resulted in enhanced hydrophilicity in either treatment modalities with a significant difference compared to the negative control group (p < 0.05). In all test groups, the hydrophilicity was enhanced compared to the negative control group (p < 0.05). Diode laser treatment had the least disruptive effect on the Ti surface characteristics. The use of other mechanical methods caused significant alterations in the surface roughness.
Purpose:
This study aimed to explore the antimicrobial properties of graphene coated Ti-6Al-4V to oral pathogens.
Materials and methods:
Graphene directly synthesized on Ti-6Al-4V alloy was characterized by scanning electron microscopy (SEM) and Raman spectroscopy. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, live/dead fluorescent staining and SEM were used to analyze the antimicrobial properties of graphene coated Ti-6Al-4V alloy to Porphyromonas gingivalis (P. gingivalis), Fusobacterium nucleatum (F. nucleatum) and Candida albicans (C. albicans). Reactive oxygen species (ROS) generation was monitored to reveal the antimicrobial mechanism.
Results:
Graphene coated Ti-6Al-4V alloy caused a significant reduction in the presence of both bacterial and fungal pathogens as compared to uncoated Ti-6Al-4V alloy. P. gingivalis, F. nucleatum and C. albicans on graphene coated Ti-6Al-4V alloy were less active than them on uncoated Ti-6Al-4V alloy, and tended to become shrunk and deformed. Meanwhile, graphene coated Ti-6Al-4V alloy induced more generation of ROS in the pathogens than uncoated Ti-6Al-4V alloy.
Conclusions:
Graphene coated Ti-6Al-4V alloy exhibited antimicrobial properties against oral pathogens, the induction of oxidative stress might be involved in its antimicrobial mechanisms. This article is protected by copyright. All rights reserved.
Periodontitis is an inflammatory disease caused by biofilm accumulation and dysbiosis in subgingival areas surrounding the teeth. If not properly treated, this oral disease may result in tooth loss and consequently poor esthetics, deteriorated masticatory function and compromised quality of life. Epidemiological and clinical intervention studies indicate that periodontitis can potentially aggravate systemic diseases, such as, cardiovascular disease, type 2 diabetes mellitus, rheumatoid arthritis, and Alzheimer disease. Therefore, improvements in the treatment of periodontal disease may benefit not only oral health but also systemic health. The complement system is an ancient host defense system that plays pivotal roles in immunosurveillance and tissue homeostasis. However, complement has unwanted consequences if not controlled appropriately or excessively activated. Complement overactivation has been observed in patients with periodontitis and in animal models of periodontitis and drives periodontal inflammation and tissue destruction. This review places emphasis on a promising periodontal host-modulation therapy targeting the complement system, namely the complement C3-targeting drug, AMY-101. AMY-101 has shown safety and efficacy in reducing gingival inflammation in a recent Phase 2a clinical study. We also discuss the potential of AMY-101 to treat peri-implant inflammatory conditions, where complement also seems to be involved and there is an urgent unmet need for effective treatment.
This chapter focuses on the complications that can lead to peri‐implant disease (mucositis and implantitis). It establishes that dental implant complications are common and may be due to a variety of etiologies and may be classified as prosthetic or biologic. The chapter includes special contributions from by Dr. Maria L. Geisinger (implant complications and peri‐implant disease), Dr. Gerrarda O'Beirne (biofilm), and Dr. Luciana Safioti (corrosion). Osteoporosis/osteopenia have risk factors with periodontal and peri‐implant diseases, including cigarette smoking, dietary factors, and medications, but periodontal disease has been associated with bone density and osteoporosis diagnosis. Plaque control delivered by patients and professionals can result in a reduction in clinical signs of peri‐implant inflammation. As the oral biofilm grows, an extracellular matrix is formed to envelope, nourish, and protect the growing mass. The presence of Streptococcus mutans, responsible for the release of oral acid, also renders anacidic environment that reduces the corrosion resistance of titanium.
[This corrects the article DOI: 10.1371/journal.pone.0210530.].
Background
Titanium (Ti) and its alloys possess high biocompatibility and corrosion resistance due to Ti ability to form a passive oxide film, i.e. TiO2, immediately after contact with oxygen. This passive layer is considered stable during function in the oral cavity, however, emerging information associate inflammatory peri-implantitis to vast increases in Ti corrosion products around diseased implants as compared to healthy ones. Thus, it is imperative to identify which factors in the peri-implant micro-environment may reduce Ti corrosion resistance.
Methods
The aim of this work is to simulate peri-implant inflammatory conditions in vitro to determine which factors affect corrosion susceptibility of Ti-6Al-4V dental implants. The effects of hydrogen peroxide (surrogate for reactive oxygen species, ROS, found during inflammation), albumin (a protein typical of physiological fluids), deaeration (to simulate reduced pO2 conditions during inflammation), in an acidic environment (pH 3), which is typical of inflammation condition, were investigated. Corrosion resistance of Ti-6Al-4V clinically-relevant acid etched surfaces was investigated by electrochemical techniques: Open Circuit Potential; Electrochemical Impedance Spectroscopy; and Anodic Polarization.
Results
Electrochemical tests confirmed that most aggressive conditions to the Ti-6Al-4V alloy were those typical of occluded cells, i.e. oxidizing conditions (H2O2), in the presence of protein and deaeration of the physiological medium.
Conclusions
Our results provide evidence that titanium’s corrosion resistance can be reduced by intense inflammatory conditions. This observation indicates that the micro-environment to which the implant is exposed during peri-implant inflammation is highly aggressive and may lead to TiO2 passive layer attack. Further investigation of the effect of these aggressive conditions on titanium dissolution is warranted.
Implant surface characteristics, as well as physical and mechanical properties, are responsible for the positive interaction between the dental implant, the bone and the surrounding soft tissues. Unfortunately, the dental implant surface does not remain unaltered and changes over time during the life of the implant. If changes occur at the implant surface, mucositis and peri-implantitis processes could be initiated; implant osseointegration might be disrupted and bone resorption phenomena (osteolysis) may lead to implant loss. This systematic review compiled the information related to the potential sources of titanium particle and ions in implant dentistry. Research questions were structured in the Population, Intervention, Comparison, Outcome (PICO) framework. PICO questionnaires were developed and an exhaustive search was performed for all the relevant studies published between 1980 and 2018 involving titanium particles and ions related to implant dentistry procedures. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for the selection and inclusion of the manuscripts in this review. Titanium particle and ions are released during the implant bed preparation, during the implant insertion and during the implant decontamination. In addition, the implant surfaces and restorations are exposed to the saliva, bacteria and chemicals that can potentially dissolve the titanium oxide layer and, therefore, corrosion cycles can be initiated. Mechanical factors, the micro-gap and fluorides can also influence the proportion of metal particles and ions released from implants and restorations.
Background
Recent data support the implication of accelerated titanium dissolution products in peri‐implantitis. It is unknown whether these dissolution products have an effect on the peri‐implant microbiome, the target of existing peri‐implantitis therapies.
Purpose
This study assessed the relationship between the peri‐implant microbiome, dissolved titanium levels, and peri‐implantitis.
Materials and Methods
Clinical, microbiome, and titanium data were collected from a periodontal population having implants in function for 10 years. Clinical examinations were performed, and submucosal plaque samples were collected from the deepest site per implant. An aliquot of the sample was used for 16S rRNA gene sequencing, with the remainder analyzed for titanium quantity using mass spectrometry. Sequences were clustered into taxonomic units at 97% minimum sequence similarity using the QIIME pipeline approach.
Results
Fifteen implants were assessed. According to established case definitions, six had a diagnosis of peri‐implantitis; nine were healthy. The genera Streptococcus, Prevotella and Haemophilus characterized peri‐implant health. Peri‐implantitis was associated with a marked increase in Veillonella. Quantities of dissolved titanium were identified in 40% of sites. Titanium presence was associated with peri‐implant disease status (P = .02) and correlated to the first principal component of the microbiome (rho = 0.552) and its alpha‐diversity (rho = −0.496). Canonical correlation analyses found that titanium levels, but not health or disease status of the implant, were significantly associated with the microbiota composition (P = .045).
Conclusions
These findings suggest an association between titanium dissolution products and peri‐implantitis and support a role for these products in modifying the peri‐implant microbiome structure and diversity.
Peri-implantitis is a destructive inflammatory process affecting tissues surrounding dental implants and it is considered a new global health concern. Human studies have suggested that the frequencies of Langerhans cells (LCs), the main antigen-presenting cells (APCs) of the oral epithelium, are dysregulated around the implants. Since LCs play a role in regulating oral mucosal homeostasis, we studied the impact of dental titanium implants on LC differentiation using a novel murine model. We demonstrate that whereas the percentage of LC precursors (CD11c⁺MHCII⁺) increased in the peri-implant epithelium, the frequencies of LCs (CD11c⁺MHCII⁺EpCAM⁺langerin⁺) were significantly reduced. Instead, a population of partially developed LCs expressing CD11c⁺MHCII⁺EpCAM⁺ but not langerin evolved in the peri-implant mucosa, which was also accompanied by a considerable leukocyte infiltrate. In line with the increased levels of LC precursors, expression of CCL2 and CCL20, chemokines mediating their translocation to the epithelium, was elevated in the peri-implant epithelium. However, expression of TGF-β1, the major cytokine driving final differentiation of LCs, was reduced in the epithelium. Further analysis revealed that while the expression of the TGF-β1 canonical receptor activing-like kinase (ALK)5 was upregulated, expression of its non-canonical receptor ALK3 was decreased. Since titanium ions releasing from implants were proposed to alter APC function, we next analyzed the impact of such ions on TGF-β1-induced LC differentiation cultures. Concurring with the in vivo studies, the presence of titanium ions resulted in the generation of partially developed LCs that express CD11c⁺MHCII⁺EpCAM⁺ but failed to upregulate langerin expression. Collectively, these findings suggest that titanium dental implants have the capacity to impair the development of oral LCs and might subsequently dysregulate immunity in the peri-implant mucosa.
Background: This retrospective analysis aimed at comparing the clinical outcomes following combined surgical therapy of peri-implantitis at initially grafted and non-grafted (i.e. pristine) implant sites.
Methods: A total of 39 patients exhibiting 57 implants diagnosed with peri-implantitis (i.e. 16 implants at grafted and 41 implants at non-grafted sites) were included. Each subject had received a combined (i.e. implantoplasty and augmentative therapy) surgical treatment proce-dures at respective implants (grafted sites: 10 patients, 16 implants, non-grafted sites: 29 pa-tients, 41 implants). A chi - squared test (χ2) was used to assess whether the initial grafting procedure did affect the treatment outcomes (i.e. disease resolution, bleeding on probing – BOP, probing pocket depths - PD). The mean follow-up period was 41.9±34.75 months.
Results: At the patient level, disease resolution (i.e. absence of BOP and PD ≥ 6 mm) was obtained in 4/10 (40%) at grafted and in 7/27 (24.1%) at non-grafted implant sites (p = 0.579). BOP reductions was found to be 60.64±40.81% at non-grafted and 77.45±30.92% at grafted sites (p = 0.778). PD reductions amounted to 2.20±2.22 mm at non-grafted and 1.57±1.54 mm at grafted sites (p = 0.969).
Conclusions: The initial bone-grafting procedures at the implant sites did not influence the effectiveness of combined surgical therapy of peri-implantitis.
With millions of new dental and orthopedic implants inserted annually, periprosthetic osteolysis becomes a major concern. In dentistry, peri-implantitis management includes cleaning using ultrasonic scaling. We examined whether ultrasonic scaling releases titanium particles and induces inflammation and osteolysis. Titanium discs with machined, sandblasted/acid-etched and sandblasted surfaces were subjected to ultrasonic scaling and we physically and chemically characterized the released particles. These particles induced a severe inflammatory response in macrophages and stimulated osteoclastogenesis. The number of released particles and their chemical composition and nanotopography had a significant effect on the inflammatory response. Sandblasted surfaces released the highest number of particles with the greatest nanoroughness properties. Particles from sandblasted/acid-etched discs induced a milder inflammatory response than those from sandblasted discs but a stronger inflammatory response than those from machined discs. Titanium particles were then embedded in fibrin membranes placed on mouse calvariae for 5 weeks. Using micro-CT, we observed that particles from sandblasted discs induced more osteolysis than those from sandblasted/acid-etched discs. In summary, ultrasonic scaling of titanium implants releases particles in a surface type-dependent manner and may aggravate peri-implantitis. Future studies should assess whether surface roughening affects the extent of released wear particles and aseptic loosening of orthopedic implants.
Background and objective:
Peri-implantitis is a destructive inflammatory process characterized by destruction of the implant-supporting bone. Inflammasomes are large intracellular multiprotein complexes that play a central role in innate immunity by activating the release of proinflammatory cytokines. Although inflammasome activation has previously been linked to periodontal inflammation, there is still no information on a potential association with peri-implantitis. The aim of this study was to examine cytotoxic and proinflammatory effects, including inflammasome activation, of metals used in dental implants, in an in vitro model, as well as from clinical tissue samples.
Material and methods:
Human macrophages were exposed to different metals [titanium (Ti), cobalt, chromium and molybdenum] in a cell-culture assay. Cytotoxicity was determined using the neutral red uptake assay. Cytokine secretion was quantified using an ELISA, and the expression of genes of various inflammasome components was analysed using quantitative PCR. In addition, the concentrations of interleukin-1β (IL-1β) and Ti in mucosal tissue samples taken in the vicinity of dental implants were determined using ELISA and inductively coupled plasma mass spectrometry, respectively.
Results:
Ti ions in physiological solutions stimulated inflammasome activation in human macrophages and consequently IL-1β release. This effect was further enhanced by macrophages that have been exposed to lipopolysaccharides. The proinflammatory activation caused by Ti ions disappeared after filtration (0.22 μm), which indicates an effect of particles. Ti ions alone did not stimulate transcription of the inflammasome components. The Ti levels of tissue samples obtained in the vicinity of Ti implants were sufficiently high (≥ 40 μm) to stimulate secretion of IL-1β from human macrophages in vitro.
Conclusion:
Ti ions form particles that act as secondary stimuli for a proinflammatory reaction.
Background:
Chemotherapeutic agents (ChAs) are considered an integral part of current treatment protocols for the decontamination of titanium (Ti) implants with peri-implantitis, based on their antimicrobial effect. Despite the proven antimicrobial effect of ChAs on titanium-bound biofilms, previous studies have elucidated an unexpected disassociation between bacterial reduction and biologically acceptable treatment outcomes. In this study we hypothesized that ChAs residues alter Ti physicochemistry, and thus compromise cellular response to decontaminated surfaces.
Methods:
Grit-blasted acid-etched Ti discs were contaminated with multi-species microcosms grown from in vivo peri-implant plaque samples. To simulate implant decontamination, we burnished the contaminated discs with either 0.12%-chlorhexidine, 20%-citric acid, 24%-EDTA/1.5%-NaOCl, or sterile saline, and assessed surface physicochemical properties. Sterile untreated surfaces were the controls. Biologic effects of decontamination were assessed via cell proliferation and differentiation assays.
Results:
Bacterial counts after decontamination confirmed that the ChAs were antimicrobial. XPS invariably detected elemental contaminants associated with each ChA molecule or salt that significantly altered wettability compared to controls. Notably, all surfaces with ChA-residues showed some cytotoxic effect compared to controls (p<.05). Increased cell counts were consistently found in the saline-treated group compared to chlorhexidine (p=.03). Interestingly, no association was found between antimicrobial effect and cell counts (p>.05).
Conclusion:
ChA-specific residues that were left on the Ti surfaces altered titanium physical properties and adversely affected osteoblastic response irrespective of their observed antimicrobial effect. Chlorhexidine may compromise the biocompatibility of titanium surfaces, and its use is not recommended to detoxify implants. Sterile saline, citric acid and NaOCl-EDTA may be proposed for use in the treatment of peri-implantitis. Contrary to previous studies that recommended the selection of ChAs for the decontamination of Ti implants according to their antimicrobial effects, we demonstrated that the restoration of the biocompatibility of contaminated titanium surfaces is also contingent upon the preservation of titanium material properties.
Background:
Insufficient information is currently available on the exact prevalence and the standard therapeutic protocol of peri-implant diseases. The aim of this survey was to investigate the perceived prevalence, etiology and management of peri-implant mucositis and peri-implantitis of US periodontists.
Methods:
A twenty question survey was developed. Periodontists currently practicing in the US were contacted by e-mail providing a link to access the survey.
Results:
280 periodontists - 79.3% males, 62.9% with >10 years in practice, 75.7% in private practice -completed the survey. 96.1% of the participants were placing implants, 58.3% for >10 years and 32.4% >150 implants/year. The majority reported that the prevalence of peri-implant mucositis and peri-implantitis in their practices is up to 25% but is higher in the general US population and that up to 10% of implants must be removed due to peri-implantitis. There was agreement as to the role of plaque, smoking and adverse loading as etiological factors, as well as to the use of oral hygiene, an antimicrobial gel/mouth rinse, non-surgical debridement, use of systemic antibiotics and 3-month supportive care for treatment of peri-implantitis. A significant heterogeneity was recorded in relation to the instruments used for debridement, use and type of surgical treatment, and materials used for regeneration. Only 5.1% believed that treatment is very effective.
Conclusions:
This survey indicates that peri-implant diseases are a frequently encountered problem in periodontal practices and that the absence of a standard therapeutic protocol results in significant empirical use of therapeutic modalities and a moderately effective treatment outcome.
Peri-implant diseases are becoming a major health issue in dentistry. Despite the magnitude of this problem and the potential grave consequences, commonly acceptable treatment protocols are missing. Hence, the present paper reviews the literature treatment of peri-implantitis in order to explore their benefits and limitations. Treatment of peri-implantitis may include surgical and nonsurgical approaches, either individually or combined. Nonsurgical therapy is aimed at removing local irritants from the implants' surface with or without surface decontamination and possibly some additional adjunctive therapies agents or devices. Systemic antibiotics may also be incorporated. Surgical therapy is aimed at removing any residual subgingival deposits and additionally reducing the peri-implant pockets depth. This can be done alone or in conjunction with either osseous respective approach or regenerative approach. Finally, if all fails, explantation might be the best alternative in order to arrest the destruction of the osseous structure around the implant, thus preserving whatever is left in this site for future reconstruction. The available literature is still lacking with large heterogeneity in the clinical response thus suggesting possible underlying predisposing conditions that are not all clear to us. Therefore, at present time treatment of peri-implantitis should be considered possible but not necessarily predictable.
Corrosion of titanium dental implants has been associated with implant failure and is considered one of the triggering factors for peri-implantitis. This corrosion is concerning, because a large amount of metal ions and debris are generated in this process, the accumulation of which may lead to adverse tissue reactions in vivo. The goal of this study is to investigate the mechanisms for implant degradation by evaluating the surface of five titanium dental implants retrieved due to peri-implantitis. The results demonstrated that all the implants were subjected to very acidic environments, which, in combination with normal implant loading, led to cases of severe implant discoloration, pitting attack, cracking and fretting-crevice corrosion. The results suggest that acidic environments induced by bacterial biofilms and/or inflammatory processes may trigger oxidation of the surface of titanium dental implants. The corrosive process can lead to permanent breakdown of the oxide film, which, besides releasing metal ions and debris in vivo, may also hinder re-integration of the implant surface with surrounding bone.
Purpose. Peri-implantitis is one of the major causes of implant failure. The detoxification of the implant surface is necessary to obtain reosseointegration. The aim of this review was to summarize in vitro and in vivo studies as well as clinical trials that have evaluated surgical approaches for detoxification of the implant body surfaces. Materials and Methods. A literature search was conducted using MEDLINE (PubMed) from 1966 to 2013. The outcome variables were the ability of the therapeutic method to eliminate the biofilm and endotoxins from the implant surface, the changes in clinical parameters, radiographic bone fill, and histological reosseointegration. Results. From 574 articles found, 76 were analyzed. The findings, advantages, and disadvantages of using mechanical, chemical methods and lasers are discussed. Conclusions. Complete elimination of the biofilms is difficult to achieve. All therapies induce changes of the chemical and physical properties of the implant surface. Partial reosseointegration after detoxification has been reported in animals. Combination protocols for surgical treatment of peri-implantitis in humans have shown some positive clinical and radiographic results, but long-term evaluation to evaluate the validity and reliability of the techniques is needed.
Metagenomic shotgun sequencing data can identify microbes populating a microbial community and their proportions, but existing taxonomic profiling methods are inefficient for increasingly large data sets. We present an approach that uses clade-specific marker genes to unambiguously assign reads to microbial clades more accurately and >50× faster than current approaches. We validated our metagenomic phylogenetic analysis tool, MetaPhlAn, on terabases of short reads and provide the largest metagenomic profiling to date of the human gut. It can be accessed at http://huttenhower.sph.harvard.edu/metaphlan/.
Background:
Oral exfoliative cytology is a diagnostic method that involves the study of cells exfoliated from the oral mucosa. Ions/particles released from metallic implants can remain in the peri-implant milieu. The aim of the present study is to assess the presence of metal particles in cells exfoliated from peri-implant oral mucosa around titanium dental implants.
Methods:
The study comprised 30 patients carrying titanium dental implants, who had neither a metallic prosthesis nor metal restorations in neighboring teeth. Individuals undergoing orthodontic therapy and those who had oral piercing were also excluded from the study. The study sample included patients with and without peri-implantitis. Cytologic samples of the peri-implant area were collected. Samples of the marginal gingiva on the contralateral side of the implant were taken from the same individuals to serve as control. Cytologic analysis was performed using light microscopy. Titanium concentration was determined using inductively coupled plasma-mass spectrophotometry.
Results:
Metal-like particles were observed inside and outside epithelial cells and macrophages in cytologic smears of peri-implant mucosa of both patients with and without peri-implantitis. No particles were found in the control cytologic samples. The concentration of titanium was higher in the peri-implantitis group compared with the group without peri-implantitis; no traces of titanium were observed in controls.
Conclusions:
Regardless of an inflammatory response, ions/particles are released from the surface of the implant into the biologic milieu. Exfoliative cytology is a simple technique that may be used to detect metal particles in cells exfoliated from the peri-implant mucosa.
The use of nanoparticles (NPs) has increased in the past few years in various fields, including defence, aerospace, electronics, biology, medicine, and so forth. and in applications such as diagnostic technology, bioimaging, and drug/gene delivery. Thus, human exposure to NPs and nanomaterials is unavoidable and will certainly expand in the future resulting in a growing interest in nanotoxicology, the study of toxicity of nanomaterials. A number of studies have reported the effects of NPs in respect to pulmonary inflammation by investigating in vitro activation of pulmonary cells with NPs and in vivo in a variety of models in which neutrophils appear to be the predominant leukocyte cell type in lungs and in bronchoalveolar lavages following inhalation or intratracheal instillation of NPs. Despite the fact that several studies have reported an increased number of neutrophils, the literature dealing with the direct activation of neutrophils by a given NP is poorly documented. This paper will summarize the current literature in this latter area of research and will end with a perspective view in which our laboratory will be involved in the following years.
The main aim of this work was to study the simultaneous wear-corrosion of titanium (Ti) in the presence of biofilms composed of Streptococcus mutans and Candida albicans. Both organisms were separately grown in specific growth media, and then mixed in a medium supplemented with a high sucrose concentration. Corrosion and tribocorrosion tests were performed after 48 h and 216 h of biofilm growth. Electrochemical corrosion tests indicated a decrease in the corrosion resistance of Ti in the presence of the biofilms although the TiO2 film presented the characteristics of a compact oxide film. While the open circuit potential of Ti indicated a tendency to corrosion in the presence of the biofilms, tribocorrosion tests revealed a low friction on biofilm covered Ti. The properties of the biofilms were similar to those of the lubricant agents used to decrease the wear rate of materials. However, the pH-lowering promoted by microbial species, can lead to corrosion of Ti-based oral rehabilitation systems.
Introduction:
Epigenetic changes are associated with various inflammatory diseases and are influenced by environmental factors. Recent data support an association between titanium dissolution products and peri-implantitis. We hypothesize that site-specific changes in gene methylation, a form of epigenetic regulation, around dental implants may be influenced by local environmental factors, such as titanium dissolution particles.
Objectives:
The primary purpose of this study was to assess global methylation patterns related to the disease status of dental implants and the concentration of titanium particles.
Methods:
We assessed peri-implantitis cases defined according to established definitions from a cross-sectional study that had implants in function for at least 2 y. Controls were sampled from the same population and had healthy implants. Peri-implant crevicular fluid samples were collected and prepared for immunohistochemical analysis of 5-methylcytosine (5mC), and submucosal plaque samples were collected and subjected to inductively coupled plasma mass spectrometry (ICP-MS) for measuring titanium. Data were analyzed via generalized estimating equation models to account for multiple implants per participant.
Results:
Forty participants were included; 21 implants with peri-implantitis and 24 healthy implants were included in the analysis. Epigenetic alterations in global gene methylation were significantly more pronounced in peri-implantitis cases as compared to controls (P = 0.002). Adjustment for smoking status further strengthened the association (P = 0.0079). Higher adjusted titanium quantities had significantly higher 5mC (P < 0.001).
Conclusions:
Peri-implantitis cases exhibited increased levels of methylated DNA cytosine (5mC) as compared to controls, suggesting that peri-implantitis is associated with epigenetic alterations in the peri-implant tissues. In addition, the finding that titanium concentrations were associated with global methylation levels independent of peri-implantitis status suggests that methylation may be affected by titanium dissolution products. Collectively, these results support further investigations to determine if these associations are causal or ecological in nature.
Knowledge transfer statement:
These are the first human data to elucidate the epigenetic regulation of gene transcription via hypermethylation as a potential mechanism involved in peri-implantitis. Furthermore, they identify titanium dissolution products as a potential environmental factor associated with this hypermethylation, which provides cues for novel therapeutic targets for peri-implantitis.
Background
Titanium (Ti) dominates as the material of choice for dental implant systems. Recently, titanium‐zirconium alloy (TiZr) and zirconia (ZrO₂) have emerged as alternative materials due to higher mechanical strength and lower corrosion susceptibility. Oral pathogenic bacteria can colonize Ti surfaces, leading to surface degradation, which has yet to be investigated on TiZr and ZrO2. The aim of this study was to compare in vitro oral bacterial adhesion and subsequent surface degradation on commercial Ti, TiZr, and ZrO2 implants.
Methods
Ti, TiZr, and ZrO2 implants with sandblasted, acid‐etched (SLA) surfaces in addition to modified SLA‐treated (modSLA) Ti implants (n = 3) were immersed for 30 consecutive days in Streptococcus polyculture. Post‐immersion, adherent bacterial count was quantified. Optical microscopy was used to assess qualitative degradation and score Ti‐based implants based on degree of surface damage while electrochemical testing quantified corrosion behavior. Analysis of variance followed by post‐hoc Tukey test was used to statistically compare quantitative results (α = 0.05).
Results
Ti‐SLA, Ti‐modSLA, and TiZr‐SLA implants exhibited localized features characteristic of corrosion attack while ZrO2‐SLA implants experienced minimal changes in surface morphology as compared to non‐immersed control. Corrosion features were more numerous on Ti‐modSLA implants but smaller in size as compared to those on Ti‐SLA and TiZr‐SLA implants. No significant differences in corrosion resistance (polarization resistance and corrosion rate) were observed between Ti‐SLA, Ti‐modSLA, and TiZr‐SLA implants.
Conclusion
TiZr and ZrO2 dental implant surfaces were not more susceptible to colonization and surface degradation by oral Streptococcus species than commercially pure Ti implants.
This article is protected by copyright. All rights reserved
Objectives
This narrative review provides an evidence‐based overview on peri‐implantitis for the 2017 World Workshop on the Classification of Periodontal and Peri‐Implant Diseases and Conditions.
Methods
A literature review was conducted addressing the following topics: 1) definition of peri‐implantitis; 2) conversion from peri‐implant mucositis to peri‐implantitis, 3) onset and pattern of disease progression, 4) characteristics of peri‐implantitis, 5) risk factors/indicators for peri‐implantitis, and 6) progressive crestal bone loss in the absence of soft tissue inflammation.
Conclusions
• 1) Peri‐implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri‐implant connective tissue and progressive loss of supporting bone.
• 2) The histopathologic and clinical conditions leading to the conversion from peri‐implant mucositis to peri‐implantitis are not completely understood.
• 3) The onset of peri‐implantitis may occur early during follow‐up and the disease progresses in a non‐linear and accelerating pattern.
• 4a) Peri‐implantitis sites exhibit clinical signs of inflammation and increased probing depths compared to baseline measurements.
• 4b) At the histologic level, compared to periodontitis sites, peri‐implantitis sites often have larger inflammatory lesions.
• 4c) Surgical entry at peri‐implantitis sites often reveals a circumferential pattern of bone loss.
• 5a) There is strong evidence that there is an increased risk of developing peri‐implantitis in patients who have a history of chronic periodontitis, poor plaque control skills, and no regular maintenance care after implant therapy. Data identifying “smoking” and “diabetes” as potential risk factors/indicators for peri‐implantitis are inconclusive.
• 5b) There is some limited evidence linking peri‐implantitis to other factors such as: post‐restorative presence of submucosal cement, lack of peri‐implant keratinized mucosa and positioning of implants that make it difficult to perform oral hygiene and maintenance.
• 6) Evidence suggests that progressive crestal bone loss around implants in the absence of clinical signs of soft tissue inflammation is a rare event.
Aim
Peri‐implantitis is a common cause of late implant failure. Studies have investigated different treatment strategies. The effectiveness of these modalities, however, remains unclear. This study aimed to evaluate the success of surgical peri‐implantitis treatment using clinical and radiographic parameters.
Material and methods
A systematic review of published literature was employed. Key words were selected to conduct an electronic search using four databases for literature on human clinical studies. Meta‐analyses were carried out for clinical probing, pocket depth and radiographic bone level.
Results
A total of 16 papers met the inclusion criteria. Four treatment modalities to supplement mechanical debridement were identified: (i) apically repositioned flap, (ii) chemical surface decontamination, (iii) implantoplasty, and (iv) bone augmentation. Inconsistent results were evident which were dependent on several treatment‐independent factors. No clinical benefits were identified for the additional use of surface decontamination, while limited evidence demonstrated improvement of clinical and radiographic outcomes after implantoplasty. The effect of bone augmentation appeared limited to ‘filling’ radiographic defects.
Conclusions
The outcomes of the currently available surgical interventions for peri‐implantitis remain unpredictable. There is no reliable evidence to suggest which methods are the most effective. Further randomised‐controlled studies are needed to identify the best treatment methods.
Bacterial peri-implant biofilms, and the chemotherapeutics for their removal alter titanium surface cytocompatibility. In this study we aimed to assess the adjunctive use of an osteostimulative biomaterial utilizing a peri-implantitis model under the hypothesis that it will increase cell migration towards treated titanium surfaces. Acid-etched titanium surfaces were inoculated with a multi-species biofilm model and treated with 1.5% NaOCl in a previously characterized in vitro peri-implantitis model. Cell migration of MG63 cells towards the treated titanium surface (CTRL) was significantly reduced following inoculation with biofilm and chemotherapeutic treatment as compared to sterile controls. Addition of a tricalcium phosphate biomaterial (TCP) as a control for Ca⁺² had a small non-significant effect, while BG significantly increased MG63 chemotaxis to titanium to levels comparable to sterile (STE). Similarly, cell viability at 5 days was increased in BG and TCP as compared to CTRL. SEM imaging confirmed the improved cytocompatibility of BG and TCP surfaces as compared to CTRL. Osteostimulative BG exhibited a strong chemotactic effect to osteoblasts, which was stronger than what was expected due to the chemotactic effect of Ca⁺² alone (TCP). In addition, substantially increased cell attachment and viability was found on treated implant surfaces as compared to CTRL. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018.
Peri-implant diseases affecting the surrounding structures of endosseous dental implants include peri-implant mucositis and peri-implantitis. The prevalence of peri-implantitis ranges between 15% and 20% after 10 y, highlighting the major challenge in clinical practice in the rehabilitation of dental implant patients. The widespread nature of peri-implant bone loss poses difficulties in the management of biological complications affecting the long-term success of osseointegrated implant reconstructions. Metal and titanium particles have been detected in peri-implant supporting tissues. However, it remains unclear what mechanisms could be responsible for the elicitation of particle and ion release and whether these released implant-associated materials have a local and/or systemic impact on the peri-implant soft and hard tissues. Metal particle release as a potential etiologic factor has been intensively studied in the field of orthopedics and is known to provoke aseptic loosening around arthroplasties and is associated with implant failures. In dental medicine, emerging information about metal/titanium particle release suggests that the potential impact of biomaterials at the abutment or bone interfaces may have an influence on the pathogenesis of peri-implant bone loss. This mini-review highlights current evidence of metal particle release around dental implants and future areas for research.
Two- piece implant systems are mainly used in oral implantology involving an osseointegrated implant connected to an abutment, which supports prosthetic structures. It is well documented that the presence of microgaps, biofilms and oral fluids at the implant- abutment connection can cause mechanical and biological complications. The aim of this review paper was to report the degradation at the implant- abutment con-nection by wear and corrosion processes taking place in the oral cavity. Most of the retrieved studies evaluated the wear and corrosion (tribocorrosion) of titanium-based materials used for implants and abutments in artificial saliva. Electrochemical and wear tests together with microscopic techniques were applied to validate the tribocorrosion behavior of the surfaces. A few studies inspected the wear on the inner surfaces of the implant connection as a result of fatigue or removal of abutments. The studies reported increased microgaps after fatigue tests. In addition, data suggest that micro-movements occurring at the contacting surfaces can increase the wear of the inner surfaces of the connection. Biofilms and/or glycoproteins act as lubricants, although they can also amplify the corrosion of the surfaces. Consequently, loosening of the implant- abutment connection can take place during mastication. In addition, wear and corrosion debris such as ions and micro- and nanoparticles released into the surrounding tissues can stimulate peri- implant inflammation that can lead to pathologic bone resorption.
http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1600-0765/earlyview
Background:
Peri-implantitis represents a disruption of the biocompatible interface between the titanium (Ti) dioxide layer of the implant surface and the peri-implant tissues. Increasing preclinical data suggest that the peri-implantitis microbiota not only triggers an inflammatory immune response but also causes electrochemical alterations of the Ti surfaces, i.e. corrosion, that aggravate this inflammatory response. Thus, we hypothesized that there is an association between the dissolution of titanium from dental implants, which suggests corrosion, and peri-implantitis in humans. The objective of this study was to compare the levels of dissoluted titanium in submucosal plaque collected from healthy implants and implants with peri-implantitis.
Methods:
Submucosal plaque from N=20 implants with peri-implantitis and N=20 healthy implants was collected with sterile curettes (N=30 participants). Levels of titanium were quantified using inductively coupled plasma mass spectrometry (ICP-MS) and normalized for mass of bacterial DNA per sample to exclude confounding by varying amounts of plaque per site. Statistical analysis was performed utilizing Generalized Estimated Equations (GEE) to adjust for clustering of implants per subject.
Results:
Implants with peri-implantitis harbored significantly higher mean levels of titanium (0.85 ± 2.47) versus healthy implants (0.07 ± 0.19) after adjusting for amount of plaque collected per site (p-value=0.033).
Conclusions:
Greater levels of dissoluted titanium were detected in submucosal plaque around implants with peri-implantitis when compared to healthy implants, indicating an association between Ti dissolution and peri-implantitis. Factors triggering titanium dissolution as well as the role of titanium corrosion in the peri-implant inflammatory process warrant further investigation.
Objectives:
Dental peri-implantitis is characterized by a multifactorial etiology. The role of metal elements as an etiological factor for peri-implantitis is still unclear. The aim of this study was to investigate the incidence of metal elements in bone and mucosal tissues around dental Grade 4 CP titanium implants with signs of peri-implantitis in human patients.
Methods:
In this prospective pilot study, all patients were enrolled consecutively in two study centers. Bone and soft tissue samples of patients with peri-implantitis with indication for explantation were analyzed for the incidence of different elements (Ca, P, Ti, Fe) by means of synchrotron radiation X-ray fluorescence spectroscopy (SRXRF) and polarized light microscopy (PLM). The existence of macrophages and lymphocytes in the histologic specimens was analyzed.
Results:
Biopsies of 12 patients (seven bone samples, five mucosal samples) were included and analyzed. In nine of the 12 samples (75%), the SRXRF examination revealed the existence of titanium (Ti) and an associated occurrence with Iron (Fe). Metal particles were detected in peri-implant soft tissue using PLM. In samples with increased titanium concentration, lymphocytes were detected, whereas M1 macrophages were predominantly seen in samples with metal particles.
Conclusion:
Titanium and Iron elements were found in soft and hard tissue biopsies retrieved from peri-implantitis sites. Further histologic and immunohistochemical studies need to clarify which specific immune reaction metal elements/particles induce in dental peri-implant tissue.
To study the combined effect of mechanical and chemical cleansing on a 4-day biofilm grown intra-orally on titanium discs with different surface characteristics.
Twenty subjects used a splint with two metal plates in the upper jaw. Each plate was placed in the premolar-molar region and carried four titanium discs with four different surface characteristics (OsseoSpeed(™) , TiOblast(™) , experimental and turned surface). After 4 days of biofilm growth, the discs were cleaned mechanically and chemically with saline or chlorhexidine. Following cleansing, microbial samples were obtained and analysed by culture. The titanium discs were processed for scanning electron microscope (SEM) analysis. The experiment was repeated 3 days later using delmopinol or a mixture of essential oils during cleansing.
The combination of mechanical and chemical cleansing was ineffective in complete biofilm removal from all four titanium discs. The microbiological analysis did not reveal any statistically significant differences between surface types or between cleaning agents regarding logarithmic mean counts of CFU for specific bacteria, aerobes, anaerobes or the TVC. Aerobes were more numerous than anaerobes on all surface types. The SEM analysis disclosed that the remaining biofilm on moderately rough surfaces (OsseoSpeed(™) , TiOblast(™) and experimental) was complex and firmly attached, while the biofilm on turned surface had a pattern of spread bacteria forming less clusters.
Cleansing may call for prolonged time of chemomechanical debridement and/or more effective disinfectants to suppress biofilms on dental implant surfaces.
Objective:
To determine the effectiveness of a water flosser in reducing the bleeding on probing (BOP) index around dental implants as compared to flossing.
Methods and materials:
Patients with implants were randomly assigned to one of two groups in this examiner-masked, single-center study. The study compared the efficacy of a manual toothbrush paired with either traditional string floss or a water flosser.
Results:
The primary outcome was the reduction in the incidence of BOP after 30 days. There were no differences in the percent of bleeding sites between the groups at baseline. At 30 days, 18 of the 22 (81.8%) implants in the water flosser group showed a reduction in BOP compared to 6 of the 18 (33.3%) in the floss group (P=0.0018).
Conclusions:
These results demonstrate that the water flosser group had statistically significantly greater bleeding reduction than the string floss group. The authors concluded that water flossing may be a useful adjuvant for implant hygiene maintenance.
To assess the effectiveness of different chemotherapeutic agents on biofilm-contaminated titanium surfaces.
This study used a recently described biofilm model. In experiment 1, Streptococcus mutans biofilms grown on titanium discs were treated with (1) EDTA, (2) citric acid (CA), (3) cetylpyridium chloride, (4) Ardox-X, (5) hydrogen peroxide (H(2) O(2) ), (6) chlorhexidine (CHX) and (7) water. In experiment 2, polymicrobial biofilms were treated with (1) CA, (2) Ardox-X, (3) H(2) O(2) , (4) Ardox-X followed by CA, (5) H(2) O(2) followed by CA, (6) CHX and (7) water. Aliquots of the suspended biofilms were plated and incubated anaerobically to enable counts of the total remaining viable bacteria, which were expressed as CFUs. Following incubation, the amount of protein remaining in the treated S. mutans biofilms was quantified to assess the removal potency of each treatment agent.
H(2) O(2) , Ardox-X and CA killed significantly more S. mutans compared with the other treatments. H(2) O(2) and CA removed significantly more protein than water. CA and the combination treatments were significantly more effective against the polymicrobial biofilms than CHX, H(2) O(2) and Ardox-X. The difference in the killing efficacy between CA alone and the combination treatments was not statistically significant.
Among the chemicals tested, CA demonstrated the greatest decontamination capacity with respect to both the killing and the removal of biofilm cells. This combination of effects is clinically desirable because it promotes biocompatibility and healing around a previously contaminated implant surface. These results should, however, be validated in in vivo studies.
More than 700 bacterial species have been detected in the human oral cavity. They form highly organized microbial communities and are responsible for many oral infectious diseases, such as dental caries and periodontal disease. The prevention and treatment of these diseases require a comprehensive knowledge of oral microbial communities, which largely relies on culture-dependent methods to provide detailed phenotypic and physiological analysis of these communities. However, most of the currently available laboratory media can only selectively support the growth of a limited number of bacterial species within these communities, and fail to sustain the original oral microbial diversity. In this study, using denaturing gradient gel electrophoresis (DGGE) as an index to systematically survey and analyse the selectivity of commonly used laboratory media, we developed a new medium (SHI medium) by combining the ingredients of several selected media that can support different subpopulations within the original oral microbial community derived from pooled saliva. DGGE and 454 pyrosequencing analysis showed that SHI medium was capable of supporting a more diversified community with a microbial profile closer to that of the original oral microbiota. Furthermore, 454 pyrosequencing revealed that SHI medium supported the growth of many oral species that have not before been cultured. Crystal violet assay and the confocal laser scanning microscope analysis indicated that, compared with other media, SHI medium is able to support a more complex saliva-derived biofilm with higher biomass yield and more diverse species. This DGGE-guided method could also be used to develop novel media for other complex microbial communities.
Adherent pathogen-associated molecular patterns (PAMPs) act through toll-like receptor 2 (TLR2) and TLR4 to increase the biological activity of orthopedic wear particles in cell culture and animal models of implant loosening. This study tested whether this is dependent on TLR association with lipid rafts as reported for the response to soluble TLR ligands. For this purpose, RAW264.7 murine macrophages were activated by exposure to titanium particles with adherent PAMPs, soluble lipopolysaccharide (LPS), soluble lipotecichoic acid (LTA), or heat-killed bacteria that had been extensively washed to remove soluble PAMPs. Lipid rafts were isolated by two independent methods and the location of TLR4 and TLR2 was analyzed by Western blotting. The cognate TLRs associated with lipid rafts when the macrophages were activated with soluble LPS and LTA but not after stimulation with either titanium particles with adherent PAMPs or heat-killed bacteria. The lipid raft disruptor, methyl-β-cyclodextrin, dose-dependently inhibited TNF-α release in response to LPS but had no affect on TNF-α release in response to titanium particles with adherent PAMPs. We conclude, therefore, that titanium particles with adherent PAMPs and heat-killed bacteria activate TLR2 and TLR4 in macrophages without inducing either TLR to associate with lipid rafts. These results have important implications for the mechanisms of orthopedic implant loosening as well the mechanisms for TLR activation in other inflammatory situations.
The shelf life of implantable materials has rarely been addressed. We determined whether osteoconductivity of titanium is stable over time. Rat bone marrow-derived osteoblasts were cultured on new titanium disks (immediately after acid-etching), 3-day-old (stored after acid-etching for 3 days in dark ambient conditions), 2-week-old, and 4-week-old disks. Protein adsorption capacity, and osteoblast migration, attachment, spread, proliferation and mineralization decreased substantially on old titanium surfaces in an age-dependent manner. When the 4-week-old implants were placed into rat femurs, the biomechanical strength of bone-titanium integration was less than half that for newly processed implants at the early healing stage. More than 90% of the new implant surface was covered by newly generated bone compared to 58% for 4-week-old implants. This time-dependent biological degradation was also found for machined and sandblasted titanium surfaces and was associated with progressive accumulation of hydrocarbon on titanium surfaces. The new surface could attract osteoblasts even under a protein-free condition, but its high bioactivity was abrogated by masking the surface with anions. These results uncover an aging-like time-dependent biological degradation of titanium surfaces from bioactive to bioinert. We also suggest possible underlying mechanisms for this biological degradation that provide new insights into how we could inadvertently lose, and conversely, maximize the osteoconductivity of titanium-based implant materials.
The objective of this study was to evaluate the effect of a dental water jet on plaque biofilm removal using scanning electron microscopy (SEM).
Eight teeth with advanced aggressive periodontal disease were extracted. Ten thin slices were cut from four teeth. Two slices were used as the control. Eight were inoculated with saliva and incubated for 4 days. Four slices were treated using a standard jet tip, and four slices were treated using an orthodontic jet tip. The remaining four teeth were treated with the orthodontic jet tip but were not inoculated with saliva to grow new plaque biofilm. All experimental teeth were treated using a dental water jet for 3 seconds on medium pressure.
The standard jet tip removed 99.99% of the salivary (ex vivo) biofilm, and the orthodontic jet tip removed 99.84% of the salivary biofilm. Observation of the remaining four teeth by the naked eye indicated that the orthodontic jet tip removed significant amounts of calcified (in vivo) plaque biofilm. This was confirmed by SEM evaluations.
The Waterpik dental water jet (Water Pik, Inc, Fort Collins, CO) can remove both ex vivo and in vivo plaque biofilm significantly.
Although considerable bone fill may occur following treatment of peri-implantitis, re-osseointegration appears to be limited and unpredictable. Objectives: To evaluate the effects of various decontamination techniques and implant surface configurations on re-osseointegration of contaminated dental implants.
Three months after tooth extraction, implants consisting of a basal part and an exchangeable intraosseous implant cylinder (EIIC) were placed in the mandibles of dogs. The EIIC was machined (M), sandblasted and acid-etched (SLA), or titanium plasma sprayed (TPS). Ligature-induced peri-implantitis was initiated 8 weeks post-implantation and lasted until bone loss reached the junction of the two implant parts. Three treatment modalities were applied: (T1) the EIIC was exchanged for a pristine EIIC; (T2) the EIIC was sprayed in situ with saline; and (T3) the EIIC was removed, cleansed outside the mouth by spraying with saline, steam-sterilized, and remounted. A collagen barrier was placed over each fixture, and 3 months later, samples were processed for histology and histomorphometry.
T2 revealed the highest bone-to-implant contact (BIC) level (significantly better than T1 and T3). T2 also yielded the highest bone crest level (significantly better than T1), followed by T3 (significantly better than T1). SLA showed the highest BIC level (significantly better than M), followed by TPS. There were no statistically significant differences in bone crest height between implant types.
Both SLA implants and in situ cleansing resulted in the best re-osseointegration and bone fill of previously contaminated implants.
Chlorhexidine (CHX) digluconate exerts plaque inhibitory efficacy in the natural dentition environment due to a superior degree of persistence at the tooth surface. The purpose of the present study was to assess the interaction of CHX with titanium surfaces to estimate its antiplaque potential in the peri-implant environment.
Saliva-coated machined smooth (S) and sand-blasted acid-etched rough (R) titanium disks were soaked in either 0.1% or 0.2% CHX solution. After 24 hours, CHX amounts that were adsorbed, washed out, and desorbed from the titanium surfaces were determined spectrophotometrically at 230 nm. The antibacterial activity of CHX-treated titanium disks was assessed by measuring bacterial inhibition zones on Streptococcus mutans lawns.
Titanium disks adsorbed 3% to 8% of the available CHX, which was significantly higher with 0.2% CHX (P<0.001) than with 0.1% CHX and two-fold higher on the R titanium disks compared to S titanium surface (P<0.001). After rinsing with water, 2.2% of the adsorbed CHX was washed out. Over 24 hours, S- and R-type disks released 1.1% and 0.6% of the adsorbed agent, respectively. Larger bacterial inhibition zones were obtained with 0.2% CHX and in R disks compared to S disks.
CHX displayed persistence at the titanium surface. The adsorption level and bacterial growth inhibition were affected by CHX concentration and titanium surface characteristics, with higher levels of adsorption and antibacterial activity with 0.2% CHX and rough titanium surface. The slow CHX release rate suggests persistence of this agent at the titanium-pellicle surface, which can provide a long-term antiplaque effect.
Maintenance of patients with dental implants in contemporary dental practice
- G Kotsakis
- M Goldie
- I Konstantinidis
Kotsakis G, Goldie M, Konstantinidis I. Maintenance of patients
with dental implants in contemporary dental practice. Alpha
Omegan. 2015/2016;108:10-17.
Evaluation of oral microbial corrosion on the surface degradation of dental implant materials
- DA Siddiqui
- L Guida
- S Sridhar
- P Valderrama
- TG Wilson
- DC Rodrigues
Siddiqui DA, Guida L, Sridhar S, Valderrama P, Wilson TG, Jr,
Rodrigues DC. Evaluation of oral microbial corrosion on the
surface degradation of dental implant materials. J Periodontol.
2019;90:72-81.
Maintenance of patients with dental implants in contemporary dental practice
- Kotsakis G
Corrosion of Metallic Materials and Their Characterizatin
- E Gemelli
Gemelli E. Corrosion of Metallic Materials and Their Characterizatin: LTC; 1st ed.; 2001.
- F Schwarz
- J Derks
- A Monje
- H L Wang
- Peri-Implantitis
Schwarz F, Derks J, Monje A, Wang HL. Peri-implantitis. J Periodontol. 2018;89(Suppl 1):S267-S290.