Article

Clinical Outcome of Narrow Diameter Implants: A Retrospective Study of 510 Implants

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Abstract

Narrow diameter implants ([NDIs]; diameter <3.75 mm) are a potential solution for specific clinical situations such as reduced interradicular bone, thin alveolar crest, and replacement of teeth with small cervical diameter. NDIs have been available in clinical practice since the 1990s, but only a few studies have analyzed their clinical outcome. From November 1996 to February 2004, 237 patients were selected, and 510 NDIs were inserted. Implant diameter ranged from 3.0 to 3.5 mm, multiple implant systems were used, and 255 implants were restored immediately without loading (IRWL). No statistical differences were detected among the studied variables. Consequently, marginal bone loss (MBL) was considered an indicator of the success rate (SCR) to evaluate the effect of several host-, surgery-, and implant-related factors. A general linear model (GLM) was used to detect those variables statistically associated with MBL. Only three of 510 implants were lost (survival rate [SRR] = 99.4%), and no differences were detected among the studied variables. On the contrary, the GLM showed that delayed loading and longer (>13 mm) and larger (3.4 and 3.5 mm) NDIs reduced MBL. NDIs have a high SRR and SCR, similar to those reported in previous studies of regular diameter implants. Moreover, IRWL of NDIs is a reliable procedure, although a slightly higher bone resorption is reported compared to delayed loading. No implant fractures were detected in the present series.

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... Previous studies have shown that the diameter of an implant has significant effects on the generation of tension/deformation of the peri-implant osseous tissue 12,13 . Several authors have suggested that an increase in the diameter favors the biomechanical issue for peri-implant osseous maintenance [14][15][16] . However, there are other studies that disagree with this 11,[17][18][19] . ...
... Therefore, success rate is high, as shown in several studies [12][13][14] . The use of 3.3 mm implants has also been highly satisfactory in relation to prosthetic units, with no clinical difference when compared to 4.1 mm diameter prosthetic implants in the posterior region of the mandible [14][15][16][17] . In the present study, the 4.1 mm diameter implant group showed the lowest rate of deformation in the cortical bone, half that of the 3.3 mm group, although this difference did not reflect distinct results as to the survival of the implants in these various clinical studies 14-17 . ...
... However, this success cannot be considered exclusively by survival, since several intrinsic and extrinsic factors impact on the stability of the marginal bone. As intrinsic factors, surrounding osseous quality and quantity, also adjacent soft tissues, should be considered, since the size of the osseous alveolar crest and the distance between the tooth and the implant is of critical importance for their maintenance 15,17,18 . The extrinsic factors involve the design of the implants, the size of the implant-abutment interface, the depth and angle or the intermediate abutments and, mainly, parafunctional habits such as bruxism 15 . ...
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Article
Introduction When stress and strain levels in the bone-implant system exceed It's capacity, a mechanical fatigue occurs, resulting in collapse and loss of osseointegration. Objective Analyze biomechanical behavior in single implant-supported prosthesis with implants of different diameters in the posterior mandible. Material and method Three different finite element models of Cone-Morse implants with the same height were created, varying the diameter (3.3 mm, 4.1 mm and 4.8 mm). The mandibular first molar area was the location of the implant, with It´s component and overlying prosthetic crown. The jawbone was composed of cortical and cancellous bone. Refined mesh of 0.5 mm was created in the critical interfaces to be analyzed. The loading of the models was performed at the point of occlusal contact with an occlusal load of 400 N. Result Maximum stress and strain occurred in the cervical regions of the implants in all groups, either in the implants or in components as well as in the analysis of cortical bone. The greater the diameter, the lower the stress and strain found in the implant. The 3.3 mm group had the highest strain in peri-implant cortical bone, and the 4.1 mm group had the smallest deformation, significantly lower than in the 4.8 mm group. Conclusion Although the biggest implant diameter (4.8 mm) appears to have lower values of stress and strain, the group of intermediate implant diameter (4.1 mm) showed less deformation rate in the cortical peri-implant bone. Therefore it is concluded that the 4.1 mm implant platform presented a more biomechanically effective peri-implant bone maintenance.
... Implant-supported rehabilitations rely on the concept of osseointegration, specifically at the anchorage of endosseous implants in bone (1)(2)(3)(4)(5). The rehabilitation of atrophic jaws poses a serious challenge because of limitations in bone quantity (volume and width) and, in this context, narrow-diameter or short-length implants represent a treatment alternative for rehabilitation (2,6). ...
... In the literature, the reported survival rates for short dental implants range widely (between 88% and 100%; 2,13,14). Conversely, results from previous studies on narrow-diameter implants indicate a survival rate of between 96% and 99.4% with follow-ups of 1-5 years and irrespective of the surgical approach used (two-stage surgical approach, one-stage surgical approach, or immediate-function approach; 6,[15][16][17]. However, the limited sample size (12,17) and follow-up duration (12,15) of these studies may increase potential bias, obscuring the true outcomes of fixedprosthetic rehabilitations supported by narrow-diameter or short-length implants. ...
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Article
We investigated the short-term clinical outcomes of narrow-diameter short-length implants for the fixed-prosthetic partial rehabilitation of extremely resorbed jaws. Twenty-three patients requiring partial rehabilitations with narrow-platform short-length implants in any jaw were included in this study. In total, 30 implants 3.3 mm in diameter and 7 (n = 15 implants) or 8.5 (n = 15 implants) mm in length were inserted. The primary outcome measure was implant cumulative survival rate (CSR); the secondary outcome measures were marginal bone resorption at 1 and 3 years and the incidence of biologic and mechanical complications. Five patients (21.7%) with six implants (20%) were lost to follow-up. Two implants failed in two patients, yielding a CSR at 3 years of follow-up of 93.4%. The average (standard deviation) marginal bone resorption was 1.34 mm (0.95 mm) after the first year and 1.38 mm (0.78 mm) after the third year. Biologic complications occurred in three patients; mechanical complications occurred in three patients. Despite the limitations of the study, our findings show that the use of new narrow-diameter short-length implants for the rehabilitation of extremely atrophic regions is viable in the short-term, and can be considered a treatment alternative in extremely resorbed jaws.
... Their small diameter jeopardized the belief in their long term survival, since it was said to be associated with higher marginal bone loss. 20,21,22 This made researchers recommend more than two mini implants to support a mandibular overdenture, 7 which might obviate their cost effectiveness and reduce the possibility of their parallel placement. 23 Overdentures retained by two mini implants have been, therefore, suggested by some authors. ...
... This finding is consistent with many studies who found that conventional diameter implants were associated with less marginal bone loss if compared to narrow or mini implants. 20,21 They attributed their findings to the larger implant diameter which is associated with increased implant bone contact, and hence decreased implant displacement and periimplant stresses per unit area. 22 ...
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Article
Purpose: To evaluate peri-implant marginal bone loss in two immediately loaded narrow versus standard diameter implants retaining mandibular implant overdentures. Material and methods: Twenty completely edentulous patients were collected from Outpatient Clinic of Prosthodontic Department, Faculty of Oral and Dental Medicine, Cairo University, for whom maxillary and mandibular dentures were constructed. Patients were randomly divided into two equal groups; N group which received 20 narrow (3x12 mm) and S group, 20 standard diameter implants (3.7x 12mm). Implants were immediately loaded using the previously constructed dentures, ball attachments for retention and silicone based resilient liner acting as female receptacle. Marginal bone loss was then assessed using standardized digital peri-apical radiographs at denture insertion, then 6 and 12 months later. Independent t test was used to study effect of group, while repeated measure ANOVA was used for studying effect of time on peri-implant marginal bone loss. Results were considered significant at p ≤0.05. Results: For both groups a significant difference was found among the different follow up intervals and between mesial and distal aspects of all implants at 0-6 and 0-12 months. N was associated with significantly higher bone loss if compared to S at all follow up intervals with the highest bone loss recorded at distal aspects of both groups after one year (N=1.485±0.215, S=1.062±0.125). Conclusion: Despite of the 100% one year survival rate found in both groups of the study, immediately loaded conventional diameter implants retaining mandibular overdentures are associated with lesser marginal bone loss if compared to immediately loaded narrow diameter ones.
... Although no universally accepted classification of implant diameters has been established to date, a narrow-diameter implant is generally taken to have a diameter from 3.0 mm and 3.5 mm. Some recent studies with narrow-diameter implants have reported implant success and survival rates similar to those obtained with greater diameter implants (20,21). Therefore, this study was conducted to evaluate the use of narrow dental implants in for the replacement of mandibular single rooted teeth in narrow mandibular ridges. ...
... In this study, the mean of marginal bone height increased significally towards the 6th month postoperatively. Similarly, Degidi et al (21) found a better outcome with regard to reduced crestal bone loss over time for narrow implants. ...
Article
INTRODUCTION: The possibility of placing implants can sometimes be limited due to physical conditions e.g. where the horizontal space is limited by adjacent teeth and roots, or in situations with a narrow alveolar ridge. By using a narrow implant, the need for bone augmentation or orthodontic tooth movement can be avoided. OBJECTIVES: This study was designed to evaluate the use of narrow implants for replacement of lower single rooted teeth in narrow lower ridge. MATERIALS AND METHODS: Ten patients were selected from the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Alexandria University with missing lower single rooted tooth or teeth and narrow ridge (6mm thick or less) then implants were placed and they were evaluated by radiographic examination to evaluate the bone density around the implants after 1, 3, 6 months. RESULTS: The mean periimplant probing depth was 2.18 ± 0.55 on the 3rd month and 1.50 ± 0.52 on the 6th month, there was statistically significant decrease. As for the mean marginal bone height was 0 ± 0 immediately postoperative, 0.26 ± 0.14 on the 3rd month and 0.45 ± 0.16 on the 6th month, there was statistically significant increase. Also the results of the present study showed the mean bone density was 79.63 ± 8.55 immediately postoperative then increased on the 3rd month to be 86.35 ± 6.48 and 92.01 ± 5.49 on the 6th month, there was statistically significant increase. CONCLUSIONS: Narrow diameter implants can be used to restore missing single rooted teeth with narrow ridge.
... Moreover, reports indicate that the long-term success of narrow-diameter implants is lower than that of standard-diameter implants (Winkler et al. 2000;Renouard & Nisand 2006;Romeo et al. 2006;Albrektsson et al. 2007;Ortega-Oller et al. 2014). In contrast, similar success rates have been reported in a number of long-term clinical studies (Block & Kent 1993;Saadoun & Le Gall 1996;Andersen et al. 2001;Hallman 2001;Zinsli et al. 2004;Cordaro et al. 2006;Degidi et al. 2008;Sohrabi et al. 2012;Lee et al. 2013;Zweers et al. 2015). ...
... In terms of survival rates, the scientific literature has been so far contradictory. Clinical reports indicate that the long-term success of narrow-diameter implants is lower than that of standard-diameter implants (Winkler et al. 2000;Romeo et al. 2006;Albrektsson et al. 2007) although similar rates have also been reported (Andersen et al. 2001;Hallman 2001;Zinsli et al. 2004;Cordaro et al. 2006;Degidi et al. 2008;Lee et al. 2013;Zweers et al. 2015). If the literature is carefully and comprehensively reviewed, the reason for these discrepancies can be determined. ...
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Article
Objective: This study was initiated to evaluate the 5-year implant survival rate and marginal bone levels around a 3.0-mm implant when replacing a single tooth in the anterior region. Materials and methods: The study was designed as a prospective, single-arm, multicenter clinical study. Patients missing 12, 22, 32, 31, 41 or 42 teeth were included, and implants of 3.0 mm diameter and different lengths were placed by a one-stage surgery protocol. Definitive cemented crowns were placed 6-10 weeks later. Clinical and radiographic measurements were taken at implant installation, at loading and at the 6-, 12-, 24-, 36-, 48- and 60-month follow-up visits. Results: Sixty-nine patients with 97 implants were included in this study. Four implants were lost before loading (4.12% failure rate). Implant marginal bone levels did not differ statistically after the 1-year follow-up visit. After 5 years, no bone loss was observed for 50.60% of the implants and only 8.43% of them lost more than 1 mm. Similarly, probing pocket depths and gingival zenith scores did not change significantly. Conclusions: The use of the two-piece narrow 3.0-mm titanium dental implant for the restoration of upper lateral or lower incisors is safe and results in stable marginal bone levels and probing pocket depths after 5 years of function.
... The focus of implant research is shifting from descriptions of clinical success to the identification of factors associated with failure (1) . New implant types varying in length, diameter, and shape have been continuously introduced (2) .Choice of implant depends on the type of edentulism, the volume of residual bone, the amount of space available for the prosthetic reconstruction, the emergence profile, and the type of occlusion (3) . In general, the success of dental implants is related to the quality and quantity of local bones, implant design and surgical technique (4) . ...
... Type of bone (maxilla or mandible) did not show significant statistical differences in this study, either the type of bone did not influence the success rate , or on the other hand, a second hypothesis might be that osseous class influence long term stress loading (> 5 years), Degidi et al. (3) did not find a significant difference associated with bone quality (maxilla or mandible) when evaluating survival of narrow-or wide-diameter implants. They did, however, find a different success rate according to length and diameter, with a better outcome with regard to reduced crestal bone loss over time for shorter than (13 mm) or narrower than (5.0 and 5.5 mm) implants (21) . ...
... Implants with diameter ≤ 3.5 mm are known as narrow diameter implants (NDI) [1][2][3], and have been widely recommended as mandibular implant overdenture (IOD) retainers in cases with limited bone availability. The main benefit of this implant type is that it permits a simplified and less invasive surgical technique [4][5][6][7], allowing rehabilitation of individuals who are unable to undergo invasive and long surgical procedures that would result in a prolonged healing period [8]. Elders with prolonged time since edentulism and persistent complaints related to mandibular complete denture (CD) retention, comfort, and masticatory performance are among those who benefit most from this type of implant-retained rehabilitation, especially because those issues may affect their psychosocial behavior and consequently impact their quality of life negatively [9][10][11]. ...
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Article
Objective To monitor the cytokine release patterns in the peri-implant crevicular fluid (PICF) and to investigate which factors affect the success rate of narrow diameter implants (NDI) during the first year. Material and methods Mandibular implant overdentures (IOD) retained by 2 NDI were installed in 16 clinically atrophic edentulous patients. The following parameters were monitored during the first year: (i) peri-implant health parameters (plaque index (PI), calculus presence (CP), gingival index (GI), probing depth (PD) and bleeding on probing (BoP); (ii) cytokine concentrations in the PICF (TNF-α, IL-1β, IL-6, IL-10); (iii) implant stability quotient (ISQ); (iv) marginal bone level (MBL) and bone level change (BLC); (v) implant success. The insertion torque, bone type, mandibular atrophy, time since edentulism, and smoking habits were also recorded. All data were analyzed using multivariable multilevel mixed-effects regression models. Results The variability in the TNF-α release patterns temporarily reduced at weeks (w) 8–12, while the IL-1β concentrations remained low until they peaked at w48 [p < 0.05; + 177.55 pg/μl (+ 96.13 − + 258.97)]. Conversely, IL-10 release decreased significantly at w48 [p < 0.05; − 456.24 pg/μl (− 644.41 − − 268.07)]. The PD and ISQ decreased significantly (p < 0.05) over the follow-up period, while the MBL was stable after w48 with a BLC of 0.12 ± 0.71 mm. The overall success rate was 81.3%, and was influenced by TNF-α, IL-1β, IL-10, PI, GI, PD, smoking, and time since edentulism. Conclusion Pro- and anti-inflammatory cytokine release was balanced during the first 24 weeks. The GI, smoking, and time since edentulism are the most important factors determining the implant success. Clinical relevance The study contributes to the understanding of the osseointegration process in a clinically atrophic population rehabilitated with IOD, and highlights the importance of monitoring clinical peri-implant health-related parameters, smoking habit, and time since edentulism to predict implant success rates.
... The small diameter is indicated when the residual width of the crest is limited. 39 This aspect could be explained by the reduced difference of implant diameters used in the present study compared with those used in the other studies. The association between retention mode, prosthetic type, and MBL is unclear. ...
Article
Purpose: To evaluate the influence of the crown-to-implant ratio (CI) on marginal bone loss (MBL) around short dental implants placed in the posterior mandible. Materials and methods: All patients treated with short implants (7 mm length) in the posterior mandible between 1994 and 2003 at the Dental Clinic of the Department of Neuroscience of the University of Padua (Italy) were retrospectively included in the analysis. MBL and clinical CI (cCI) were measured on the radiographs. Implant characteristics including implant diameter, prosthetic type, retention mode, antagonist type, veneering material, and implant surfaces were retrieved from local medical records. A generalized linear mixed model was estimated to identify the predictors of MBL. Results: A total of 108 dental implants placed in 51 patients were included in the analysis. Mean follow-up was 16 years (range: 11 to 20 years). Mean cCI was 2.21 (SD = 0.31) with a mean crown height of 10.86 mm (SD = 0.99). Mean MBL was 1.42 mm (SD = 0.38). At multivariable analysis, cCI ≥ 2 was associated with higher MBL (regression coefficient: 0.27; 95% CI: 0.15 to 0.40), while implant characteristics, follow-up, and site were not associated with MBL. The effect of a cCI ≥ 2 was estimated in an increase of 0.28 mm in MBL (95% CI: 0.14 to 0.43 mm). Conclusion: Higher cCI was associated with greater MBL of implant-supported fixed dental prostheses in short dental implants placed in the posterior mandible, while implant characteristics, follow-up, and site were not associated with MBL. However, the increase of 0.28 mm of MBL in patients with a cCI ≥ 2 may be not clinically relevant.
... In addition, only one of the included studies had a low risk of bias, 21 whereas the quality of the other three studies was unclear. 5,6,11 Despite good clinical results of NDI, 29,30 its mechanical properties should not be considered as the sole determinant for clinical success. The data and meta-analysis presented in the present review are not sufficient to estimate the long-term success and implant failure of NDI. ...
Article
The aim of the present study was to establish survival rates, as well as crestal bone loss (CBL) of narrow diameter implants (NDI), compared to regular diameter implants (RDI). The current review followed the Enhancing the QUAlity and Transparency Of health Research guidelines and Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. We searched main databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register) for articles addressing the focused question up to and including May 2018. Meta‐analyses were conducted for CBL and survival rates. Qualitatively, three clinical studies showed comparable CBL and survival rates between NDI and RDI at follow up. Only one study showed increased CBL around NDI compared to RDI. The overall weighted mean difference (WMD) for CBL (WMD = .06, 95% confidence interval [CI] = ‐.38‐.51, P=.76) and risk difference for survival rate (risk difference = .88, 95% CI = .22‐3.50, P=.85) were not significant between the NDI and RDI groups at follow up. NDI and RDI showed comparable CBL and survival rates. However, the findings of the present study should be interpreted with caution due to significant heterogeneity and the low number of included studies. Further randomized, controlled trials should be performed in order to obtain strong conclusions.
... 1,2 The implant diameter choice is based on several factors and, since an adequate bone volume and interdental space are required to produce good results, single-tooth rehabilitation in the anterior region can be challenging. 3 Moreover, when placed in the atrophic alveolar bone, standard-diameter implants can expose their threads and lead to failure. 4 This is common in cases of agenesis, present in 2.2% to 7.6% of the population, 5 and after tooth extraction, in which the alveolar bone resorption is progressive. 4 Other conditions, such as trauma, neoplasia, and denture wearing, are related to reduced space. ...
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Article
Objective: This study aimed to retrospectively collect clinical data to evaluate the influence of possible risk factors on the long-term success of implant treatment with extra-narrow (2.9 mm diameter) implants in a daily dental practice setting. Methodology: Data were collected from records of patients who received at least one extra-narrow implant from 2012 to 2017, regarding implant survival, prosthesis survival, patient characteristics, and implant characteristics. The association between the dependent variables "implant survival", "prosthesis survival," and "adverse events" related to patient and implant characteristics was statistically evaluated by chi-square tests. Moreover, implant and prosthesis survival were analyzed by Kaplan-Meier survival curves. Results: The sample was constituted of 58 patients (37 women and 21 men) with a mean age of 54.8 years old (SD: 12.5), followed up for up to eight years. In total, 86 extra-narrow implants were placed within this sample. Four implants were lost, resulting in an implant survival rate of 95.3%. A total of 55 prostheses were inserted and only one (1.8%) was lost, resulting in a prosthesis survival rate of 98.2%. The mean implant and prosthesis survival time was, respectively, 7.1 years and 6.3 years, according to the Kaplan-Meier survival analysis. A correlation was found between smoking and implant loss, which makes implant loss eight times more likely to occur in smokers than non-smokers. A significant association was also found between prosthesis loss and previous need of prosthesis repair. However, it was not considered clinically relevant. No association was found between the occurrence of adverse events and later implant or prosthesis loss. Conclusion: High implant and prosthesis survival rates were found in the long term for treatment with extra-narrow implants. Moreover, a significant correlation between smoking and implant loss was observed.
... 5 Narrow-diameter implants (≤3.5 mm) have been proposed to address the challenge of implant placement in cases of insufficient bone quantity, thin alveolar crest, and for the replacement of teeth with small cervical diameter. 6,7 Among the advantages of their use, the most significant is the avoidance of bone augmentation procedure which presents some side effects such as edema, pain, discomfort, and risk of nerve injury. 8 Moreover, the cost of standard diameter implant placement along with grafting procedures may be inaccessible for some patients. ...
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Article
Narrow‐diameter implants (≤3.5 mm) have been proposed to address the challenge of implant placement in cases of insufficient bone quantity, thin alveolar crest, and small cervical diameter teeth replacement The aim of this study is to report one‐year outcomes of extra‐narrow implant rehabilitation of maxillary lateral incisors, due to agenesis, in a young adult that presented sites with reduced mesiodistal and buccolingual dimensions. A 26‐year‐old male patient in need of fixed‐implant supported prostheses due to the absence of permanent maxillary lateral incisors and with limited space, was submitted to surgery to receive two 2.9 mm hybrid Morse taper connection implants with hydrophilic surfaces. Immediate loading was applied by means of insertion of provisional prostheses, which were replaced for all‐ceramic prostheses 12 months after surgery. The 1 year follow‐up showed clinical and radiographic success of extra‐narrow implant rehabilitation. Also, both regions presented good evolution of peri‐implant esthetics, as assesses using the pink esthetic score, with improvements at 4 months follow‐up and reaching high scores 12 months after surgery. Although the prosthetic rehabilitation of maxillary lateral incisors is challenging due to limited space for the insertion of implants, the clinical case suggests that the use of extra‐narrow Morse Taper implants with hybrid design and hydrophilic surface is a reliable alternative, presenting good outcomes regarding hard and soft tissue and it is a versatile solution or immediate loading procedure. Further studies are needed to confirm extra‐narrow implant predictability.
... Another direct benefit of this type of implants is the adoption of simplified and less invasive surgical techniques. 9,12,19,20 The latter results in shorter treatment and recovery times and lower costs for the patients, 12 enabling the rehabilitation of patients who cannot undergo more invasive and extensive surgical procedures. 11 Studies that evaluated patient satisfaction after treatment with NDI or MI implant-retained MO reported a direct positive impact on the patients' quality of life in terms of satisfaction, comfort and masticatory ability. ...
... 3 It has been suggested that the anatomical characteristics of the peri-implant mucosa make it more prone to inflammatory changes when compared with gingival tissues around teeth, mainly due to poorer connective tissue attachment and reduced vascular supply. 6,7 The primary etiological factors for developing PIM are the presence of biofilm and the elicited host response. A variety of other factors can contribute to the development and progression of the disease, including patientrelated, implant-related and prosthetic-related factors. ...
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Article
INTRODUCTION: Peri-implant mucositis (PIM) is characterized by inflammation of the soft tissues surrounding dental implants. It affects 43% of implant patients on average and despite its reversible nature, it can, if left untreated, progress to peri-implantitis and potentially implant failure. To date, there is a paucity of data on the prevalence of PIM in South Africa AIMS AND OBJECTIVES: To determine the prevalence of peri-implant mucositis in patients from the Faculty of Dentistry of the University of the Western Cape, and to evaluate potential risk factors including systemic (smoking, diabetes), implant-related (implant position and diameter, connection and crown) and soft tissue-related (keratinized gingiva, oral hygiene) issues. DESIGN: Cross-sectional cohort study METHODS: A total of 74 partially edentulous patients with at least one implant that had been restored with a single crown for at least 12 months were clinically examined. RESULTS AND CONCLUSIONS: PIM was highly prevalent (70.3% of the sample), highlighting the need for maintenance programs for the long-term success of dental implants. Anterior location of the implant, poor oral hygiene, pre-operative oral hygiene instructions and a wide band of KM were associated with PIM. However, due to the limited sample size, these findings should be interpreted with caution.
... (23) Other studies also showed that the failure rate of narrow implants (3-3.5 mm diameter) is not different from that of standard implants, although marginal bone loss is considerably higher in the narrow implants. (24) However, Ortega observed that narrow implant (<3.3 mm) failure rate is significantly higher than that of standard implants (>3.3 mm). (25) In addition, several studies in the literature have reported that the survival rates of standard and smaller diameter implants are between 95% and 100%, and no study had reported survival rates below 89%. ...
... Frente aos desafios inerentes à técnica, três fatores principais parecem colaborar para a manutenção dos tecidos peri-implantares após instalação imediata de implantes, como: presença e espessura da tábua óssea vestibular, cirurgia flapless, e distância entre o implante e a tábua óssea interna (gap) 6,21,25,26 . ...
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Article
Resumo O objetivo deste artigo é apresentar um protocolo de tratamento de implantes imedia-tos de excelente previsibilidade estética e biológica. O caso clínico em questão apresenta comprometimento do elemento 21, que após o exame clínico e complementar constatou a fratura radicular irreparável. O planejamento foi a exodontia da raiz fraturada e instalação de implante imediato com provisionalização imediata, associando biomaterial para preenchi-mento do gap e enxerto conjunto na vestibular. Para restauração final foram confeccionadas uma coroa zircocerâmica como restauração definitiva do elemento 21 e uma microlâmina em dissilicato de lítio (IPS e.max) no dente 11 para harmonizar contorno e proporção entre os incisivos. O resultado final obtido mostrou-se favorável no follow-up de 1 ano, tanto nos aspectos biológicos dos tecidos peri-implantares e quanto à estética final. Com isso, conclu-ímos que o protocolo adotado mostrou excelente previsibilidade. Descritores: Implantes dentários para um único dente. Abstract The aim of this paper is to present a treatment protocol for excellent aesthetic and biological predictability with immediate implant. In the reported clinical case, the element 21 was compromised with irreparable root fracture. The planning was the extraction of the fractured root and immediate implant placement with immediate temporization, associating biomaterial for gap filling and conjunctive tissue graft. For the final restoration were made a zirco-ceramic crown in the element 21, and a lithium disilicate veneer (IPS e.max) in tooth 11 to harmonize contour and ratio between the incisors. The final result was favorable along the 1 year follow-up for both biological aspects of peri-implant tissues and final aesthetic. Thus, it could be concluded that the adopted protocol showed great predictability. Descriptors: Single tooth dental implant. Prosthes. Lab. Sci. 2016; 6(21):59-69.
... Short implants were applied mainly in posterior regions presenting with advanced crestal bone resorption or pneumatization of the maxillary sinus. The threshold for reduced implant diameter was set as below 3.75 mm in width (Degidi et al., 2008), thus a total of 2.509 implants were classified as narrowdiameter implants (implant diameters ranging between 3.0 and 3.5 mm) corresponding to 19.5% of all fixtures placed. Reduced implant diameters were used in cases of horizontal bone loss, i.e. compromised buccopalatal alveolar dimension, as well as singletooth gaps in the central incisor (16.3%), lateral incisor (30.1%), canine (6.4%), first premolar (26.7%), second premolar (17.7%) or molar region (2.8%). ...
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Article
Introduction: Minimally invasive implantology using reduced implant dimensions as well as virtual treatment planning and CAD/CAM stereolithographic templates has gained popularity in recent years. The aim of the present investigation was to analyze prevailing trends in clinical utilization of these graftless therapeutic options. Material and methods: A total of 12.865 dental implants were placed in 5.365 patients at the Academy for Oral Implantology in Vienna, of which 5.5% were short (length < 10 mm), 19.5% narrow (diameter < 3.75 mm) and 10.6% template-guided. Application trends were analyzed using linear regression and compared between jaw location and dentition subgroups. Results: Use of short implants and guided surgery increased significantly in all subgroups. Narrow-diameter implants were most frequent in single-tooth gaps (24.1%), however, upward trends could only be observed in partially and completely edentulous patients. Short implants were predominantly used in the mandible (9.9% vs. 2.5%, P < 0.001) while guided surgery was favored in the maxilla (14.2% vs. 5.4%, P < 0.001). Conclusion: Short implants (most frequent in partial edentulism) and guided implant surgery (most frequent in complete edentulism) represent uprising and promising surgical approaches to avoid patient morbidity associated with bone graft surgery.
... Deep peri-implant pockets without bleeding on probing, suppuration, or other signs of inflammation [Colour figure can be viewed at wileyonlinelibrary.com]with high success rates.40 Narrow-diameter implants have high success and survival rates, similar to those reported in previous studies of regular-diameter implants.35 By increasing implant diameter, there is a significant risk of damage to the cancellous bone, which is fundamental for bone remodeling and activity via vascularization. ...
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The use of dental implants is nowadays a well‐accepted and highly predictable treatment modality for restoring the dentition and reestablishing the masticatory function of edentulous and partially edentulous patients. Despite the high predictability and excellent long‐term survival rates reported for implant therapy, complications may still occur and can jeopardize both short‐ and long‐term success. The present paper provides an overview on the most important aspects related to the etiology, prevention, and management of complications associated with implant therapy. Data from the literature indicate that a number of factors, such as surgical trauma, implant diameter, type of implant‐abutment connection, abutment disconnection and reconnection, presence of microgap, and implant malpositioning, can substantially influence the biologic processes of bone remodeling and biofilm formation, thus increasing the rate of short‐ and long‐term hard‐ and soft‐tissue complications. Other factors, such as excess cement at cement‐retained prosthetic restorations, abutment mobility, and infections (e.g. peri‐implant mucositis and peri‐implantitis) caused by bacterial biofilm, are further causes for complications and failures. More recent evidence also indicates that besides the need for sufficient bone volume surrounding the implant, the presence of an adequate width and thickness of attached mucosa may improve biofilm control and limit crestal bone resorption. Furthermore, emerging evidence points also to the pivotal role of human factors as one of the most important causes of complications in implant dentistry. It can be concluded that clinicians need to consider all biologic and biomechanical factors affecting implant placement and survival, as well as undergo adequate training to improve their surgical skills to control and prevent implant complications. Careful patient selection and control of environmental and systemic factors, such as smoking, diabetes etc., coupled with an accurate surgical and prosthetic planning, enable a better prevention and control of infections.
... [4] The short implants are indicated to retain complete, partial removable dentures and to support fixed partial denture. [5,6] Many researchers reported that the MI surgery is a noninvasive simple procedure offering numerous advantages, including decreased surgical time, less coast, improve soft tissue architecture, and hard tissue volume at the site of implant placement. [7,8] The aim of this comparative study was to evaluate the effect of different positions (interforaminal and both inter-foraminal and posterior areas) of MI supporting mandibular overdenture on the masticatory function. ...
... Hence, narrow-diameter implants can be used in patients with limited ] space without the need for additional augmentation procedures Being [1 minimally invasive, they are more accepted by the patient. Narrow diameter implants supporting single tooth replacements have shown [9,10,11,12,13,14,15,16] favorable clinical results in the long-term perspective. ...
Article
A 54-year-old female patient reported with missing anterior front tooth since past one year and wanted its replacement. After considering all factors, she was advised for an implant supported prosthesis with respect to the missing tooth. Moreover, the anterior atrophic maxilla represents a challenge for the dentist which often require hard and soft tissue augmentation procedures. Currently custom abutments are reported in having functional and esthetic advantages over prefabricated abutments. In this case report , a maxillary anterior tooth has been replaced using a narrow diameter implant using a custom abutment followed by a DMLS prosthesis placement.
... Another study examined the success of 255 NDIs that underwent immediate loading, of which, 194 were inserted into the healed bone and 61 in post-extractive sites. No statistically significant difference was reported, suggesting that even the immediate loading of NDIs placed in fresh extraction sockets should be considered as safe and predictable a procedure as those that utilize standard diameter implants (22). It has been suggested that an NDI could lead to a smaller implant/bone contact area and reduced fracture resistance (23,24). ...
... Los resultados sugieren que los implantes de diámetro pequeño se pueden utilizar con éxito en el tratamiento de pacientes parcialmente desdentados. Por otro lado, Degidi et al (6) , en el 2008, publican un estudio retrospectivo, donde desde noviembre del 1996 a febrero del 2004, seleccionaron 237 pacientes y se insertaron 510 implantes estrechos. El diámetro del implante varió de 3,0 a 3,5 mm, utilizaron múltiples sistemas de implantes y de ellos se restauraron 255 mediante provisionalización inmediata, sin carga. ...
... 8,13,42 However, the safe use posteriorly was based mainly on the high survival rates demonstrated in the anterior regions. [9][10][11][12]26,28,43,44 Klein et al 25 identified studies on 3.3-to 3.5-mm NDIs reporting survival rates between 88.9% and 100%. Nevertheless, most of these investigations considered NDI use in diverse clinical indications and not exclusively in load-bearing areas, making data specific to the posterior segments difficult to identify clearly. ...
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Statement of problem The placement of narrow-diameter implants (NDIs) in the posterior region is still debated in view of the high biomechanical risks in these areas. Purpose The purpose of this retrospective observational study was to evaluate the success and survival rates of NDIs restored with fixed prostheses in the posterior region (primary outcome) and analyze whether splinting multiple units (prosthesis design) affects the biological and mechanical complications (secondary outcome). Material and methods Dental records from 2 private clinics were reviewed for NDIs in the posterior region installed between 2009 and 2018. Ninety study participants (58 women and 32 men) aged between 21 and 84 years (mean age 49.9 years) were recalled for the assessment of implant survival and success of 160 NDIs previously provided for partial posterior edentulism associated with moderate horizontal bone loss or reduced interradicular space (105 premolars and 55 molars). The implants were restored with metal-ceramic single crowns or splinted multiple-unit prostheses, either screw-retained or cemented on customized (n=100) or stock titanium abutments (n=60). Peri-implant probing depth (PPD), bleeding on probing (BOP), bone quality, type of edentulism, and patient satisfaction were scored. The chi-square test for independence and 2-sample Welch t test were performed for statistical analysis (α=.05). Results The overall success rate was 89.37%. One implant had been removed 4 years after loading, another after 9 years, yielding a cumulative survival rate of 98.75%. Fourteen implants exhibited PPD > 5 mm. One implant and 1 abutment screw fractured, and 16 restorations demonstrated porcelain chipping. The chi-square test showed no significant relationship between prosthetic design and complications whether biological (P=.087) or mechanical (P=.805). Eighty-two percent of patients were satisfied with esthetics, 76% with function, 85% with total duration of treatment, and 90% with overall treatment cost. Conclusions Within the limitations of this retrospective study, NDIs may be considered a reliable option to replace posterior teeth. The prosthetic design had no significant impact on biological or mechanical complications.
... [2] To achieve optimal osseointegration and hence implant success the choice of an implant to be restored in a particular case is extremely important which depends on the type of edentulism, the remaining bone volume, the availability of space for the prosthetic reconstruction, the emergence profile as well as the type of occlusion. [3] However, implant placement can be limited due to the situations of either reduced bone height or presence of anatomical structures, such as the extensive maxillary sinus pneumatization and mandibular canal proximity to tooth sockets. [4,5] A short and wide-diameter implant has been suggested to restore tooth loss in the posterior region, where the dimension of the alveolus is greater than the diameter of a standard implant (3.75 mm). ...
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Background: Success of an implant depends on its placement in the bone and how well the stress and strain are distributed to the surrounding structures when occlusal force is applied to it. The size and shape of the implant plays an important role is the formation and distribution of stress and strains in the periodontium. Von Mises stresses and micromovements need to be evaluated while placing implants in D4 bone quality regions for a higher success rate. Aim: To evaluate the peri-implant Von Mises stresses, strains, and micromovements distribution in D4 bone quality around ultra-short implants of 5 mm length with varying diameters of 4 mm, 5 mm, and 6 mm. Materials and methods: The finite element method was employed to make models replacing maxillary molars in D4 type bone that was missing. Implants that could be classified as ultrashort (5 mm) were used. These implants were of varying diameters of 4, 5, and 6 mm. In each model, the implant was subjected to a force of 100 N and analyzed. The force was applied in an oblique (45 degrees) and vertical direction (90°) to the long axis of the tooth. The models were made such that they simulated cortical and cancellous anisotropic properties of the bone. The models were then analyzed using the program ANSYS workbench version 12.1. Results: When all the three diameters were compared wide diameter, i.e., 6 mm threads had the least values of peri-implant von Mises stresses, strains, and micro-movements around them. When thread shapes were taken into consideration square micro thread created the most favorable stress parameters around them with minimum values of stress, strains, and micromovements. Conclusion: Ultrashort implants combined with a wide diameter and platform switched can be used in atrophic ridges or when there is a need for extensive surgery to prepare the implant site.
... 26 Other reports conclude that there is no difference in the long-term survival rate of implants between the mandible and maxilla. 27 Yet, small-diameter implants show more marginal bone loss compared to regular diameter implants in the mandible even in the first three years after implant surgery. 16 ...
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Background Implant‐supported overdentures represent a successful treatment for edentulous patients. As early diagnosis, detection and supportive care are considered key factors for the prevention of peri‐implant diseases, consistent maintenance of these implants is becoming increasingly relevant. Purpose This retrospective analysis evaluated a cohort of edentulous patients with a mandibular implant‐supported overdenture over a period of 3.5 years during which the peri‐implant tissues were assessed. Materials and Methods A total of 108 patients that had consistently adhered to the annual maintenance appointments was selected. The clinical peri‐implant pocket probing depth (PiPPD) and peri‐implant bleeding on probing score (PiBOP) were investigated. Data from the 3.5‐year follow‐up were compared to data from the baseline assessment. Results A 100% implant survival was reported after 3.5 years. The mean PiBOP showed a significant decrease over time (P = .028). The mean PiPPD was found significantly deeper for male patients both at baseline (P = .004) and 3.5‐year follow‐up (P < .001). Besides, the PiPPD for locator anchorages was found significantly deeper compared to ball anchorages at the 3.5‐year follow‐up (P = .026). Conclusion In those patients that adhered to the annual maintenance visits during the 3.5 years after implant surgery a stable peri‐implant condition was observed. As future consideration, the comparison of the clinical outcomes of patients participating in the maintenance program with those that did not would make this observation even more meaningful.
... A literature review reported that placement of narrow diameter implants offers survival rates similar to the placement with implants of greater diameter [5][6]. However, researchers suggested that further studies are needed, with longer follow-up periods, in order to verify these reports [2,7]. ...
Article
Atrophic anterior maxilla edentulous space could pose a significant challenge to successful osseointegrated implant due to inadequate labio-palatal dimensions. The load transferring to surrounding bone is a key factor for the long-term success of implant treatment. Thus, the aim of this study was to evaluate the influence of bone quality change in age-related bone mechanical property (AMP), cortical bone thickness (CBT) and incisal relationship (ICR) on the biomechanical performance of narrow diameter implant placed in atrophic anterior maxilla via finite element method. Three-dimensional models of a narrow diameter implant and an anterior maxillary bone were constructed. Eighteen different clinical situations including two CBTs [thin (0.5 mm) and thick (1.0 mm)], three AMPs [young, middle and old ages] under three ICRs [a low overbite (LO), a mean overbite (MO), a high overbite (HO)] were studied under the loading of 50.1 N. From the results, it is crucial to consider the critical situations of narrow diameter implant placed in atrophic anterior maxilla where the combination of the thin CBT, old age-AMP and HO-ICR clinical situation which induce surrounding bone resorption and implant damage.
... 4 Studies have supported the use of NDIs in posterior regions exposed to high occlusal force, 10,22 and they have been shown to be as successful as SDIs. 10,13,23 However, studies on this subject are very limited, and there is no clear indication that NDIs can be used as an alternative to SDIs in the posterior regions. 10,22,24,25 In addition, in the posterior region, studies investigating the effects of Ti-Zr NDIs on stress distribution and comparing Ti-Zr NDIs with SDIs are sparse. ...
Article
Purpose: The purpose of the three-dimensional (3D) finite element analysis study was to compare the use of titanium-zirconium (Ti-Zr) narrow-diameter implants as an alternative to titanium (Ti) or Ti-Zr standard-diameter implants in the posterior jaw regions. Materials and methods: Ti-Zr and Ti standard-diameter implants (4.1 mm) and Ti-Zr narrow-diameter implants (3.3 mm) in cylindrical (parallel) macrodesign were simulated in the mandibular and maxillary first premolar area. Forces of 100 N were applied to the crowns in a vertical and oblique (45-degree angle to the long axis) direction. The von Mises stresses and fatigue strength values of the implants and principal stresses in the bone structures were evaluated. Results: In vertical and oblique force application, stress data in cortical and trabecular bone structures were found to be higher in 3.3-mm Ti-Zr narrow-diameter implant models than 4.1-mm Ti-Zr and Ti standard-diameter implant models. Also, the von Mises stress data of the 3.3-mm Ti-Zr narrow-diameter implants were higher than the 4.1-mm Ti-Zr and Ti standard-diameter implants. The shortest cycle of fatigue failure and estimated duration of clinical success (years) results were found in the mandibular 3.3-mm Ti-Zr implant model under oblique force, and these results remained below the identified 30-year critical threshold. Conclusion: Considering all implant models, Ti-Zr narrow-diameter implants exhibited higher stress values than Ti-Zr and Ti standard-diameter implants. In the premolar region, care should be taken biomechanically when using Ti-Zr narrow-diameter implants as an alternative to standard-diameter implants. Further comparative and in vivo studies are needed to examine the long-term success of Ti-Zr narrow-diameter implants as an alternative to standard-diameter implants.
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Purpose: The present systematic review and meta-analysis aimed to investigate the available evidence in the literature to answer the following focused question: In partially edentulous arches with reduced bone width, do implants placed after horizontal bone augmentation exhibit differences in survival and success rate compared to narrow-diameter implants placed in native bone? Materials and methods: A population, intervention, comparison and outcome question was defined and an electronic search was conducted using the MEDLINE (via PubMed) and Cochrane Oral Health Group databases to identify all studies analysing the use of standard-diameter implants inserted in regenerated bone or narrow-diameter implants for the rehabilitation of partially or completely edentulous atrophic maxillae and mandibles. Inclusion criteria and quality assessments were established, and studies were selected on this basis. Results: Twenty-four studies met the inclusion criteria and were analysed cumulatively. A comparative meta-analysis was not possible due to the lack of studies directly comparing the two rehabilitation methods in question. A cumulative implant survival rate of 97.80% (1246/1274; pooled proportion 0.984, 95% confidence interval 0.977-0.991) was reported for the narrow implants placed in atrophic ridges, while similar results were obtained for the standard-diameter implants placed in regenerated bone, with a cumulative implant survival rate of 97.94% (1332/1360; pooled proportion 0.983, 95% confidence interval 0.976-0.990). Conclusions: The present systematic review found high and comparable survival rates between narrow- and standard-diameter implants placed in regenerated bone; however, well-designed randomised controlled trials are required to support the hypothesis that both treatment strategies are successful in comparable circumstances.
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Purpose: The Authors analyzed the effect of spherical glass mega fillers (SGMF) on reducing contraction stress in dental composite resins, by means of a cavity model simulating the cuspal deflection which occurs on filled tooth cavity walls in clinical condition. Materials and methods: 20 stylized MOD cavities (C-factor = 0.83) were performed in acrylic resin. The inner surface of each cavity was sand blasted and adhesively treated in order to ensure a valid bond with the composite resin. Three different diameter of SGMF were used (i.e. 1, 1,5, 2 mm). The samples were divided in 4 groups of 5 each: Group 1 samples filled with the composite only; Group 2 samples filled with composite added with SGMFs, Ø1mm (16 spheres for each sample); Group 3 samples filled with composite added with SGMFs, Ø1,5 mm (5 spheres for each sample); Group 4 samples filled with composite added with SGMFs, Ø2 mm (2 spheres for each sample). Digital pictures were taken, in standardized settings, before and immediately after the polymerization of the composite material, placed into the cavities. With a digital image analysis software the distances from the coronal reference points of the cavity walls were measured. Then the difference between the first and second measurement was calculated. The data were analyzed by means of the ANOVA test. Results: A significative reduction on cavity walls deflection, when the composite resin is used in addiction with the SGMFs was observed. The SGMFs of smallest diameter (1mm) showed the better outcome. Conclusion: The SGMFs are reliable in reducing contraction stress in dental composite resins.
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Background: Periodontal disease (PD) is a multifactorial illness in which environment and host interact. The genetic component plays a key role in the onset of PD. In fact the genetic compound can modulate the inflammation of the mucous membranes and the loss of alveolar bone. The genetics of PD is not well understood. Previous studies suggest a strong association between PD occurrence and individual genetic profile. The role of genetic susceptibility could impact on the clinical manifestations of PD, and consequently on prevention and therapy. Materials and methods: Genetic polymorphisms of VRD, IL6 and IL10 were investigated in Italian adults affected by PD. 571 cases classified according the criteria of the American Academy of Periodontology were included. All patients were Italian coming from three areas according to italian institute of statistics (ISTAT) (www.istat.it/it/archivio/regioni). The sample comprised 379 patients from North (66%), 152 from Central (26%) and 40 of South (8%). Results: No significant differences were found among allele distribution. Conclusion: Chronic PD is a complex disease caused by a combination of genetic susceptibility, patients habits (oral hygiene, smoking, alcohol consumption) and oral pathogens. In our report no differences were detected among three Italian regions in allele distribution.
Article
Purpose: The objective of the following study is to observe the behavior of the six layers of the masseter during an isometric contraction at maximum exertion with the deformation pattern analysis method. Materials and methods: This study has been conducted by use of an ultrasound machine (MicrUs ext-1H Telemed Medical Systems Milano) and a linear probe (L12-5l40S-3 5-12 MHz 40 mm) which allowed us to record a video (DCM) comprised of 45 frames per second. The probe was fixed to a brace and the patient was asked to clench their teeth as hard as possible, obtain the muscle's maximum exertion, for 5 seconds three times, with 30 seconds intervals in between. Both right and left masseter muscles were analyzed. Then we applied to the resulting video a software (Mudy 1.7.7.2 AMID Sulmona Italy) for the analysis of muscle deformation patterns (contraction, dilatation, cross-plane, vertical strain, horizontal strain, vertical shear, horizontal shear, horizontal displacement, vertical displacement). The number of videos of masseter muscles in contraction at maximum exertion due to dental clenching made during this research is around 12,000. Out of these we chose 1,200 videos which examine 200 patients (100 females, 100 males). Results: The analysis of the deformation patterns of the masseter allows us to observe how the six layers of the muscle have different and specific functions each, which vary depending on the applied force (application point, magnitude and direction) so that we find it impossible to assign to one of the three sections of the muscle a mechanical predominance. Therefore it appears that the three parts of the muscle have specific and synergistic tasks.
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Purpose. The Authors analyzed the effect of spherical glass mega fillers (SGMF) on reducing contraction stress in dental composite resins, by means of a cavity model simulating the cuspal deflection which occurs on filled tooth cavity walls in clinical condition. Materials and methods. 20 stylized MOD cavities (C-factor = 0.83) were performed in acrylic resin. The inner surface of each cavity was sand blasted and adhesively treated in order to ensure a valid bond with the composite resin. Three different diameter of SGMF were used (i.e. 1, 1,5, 2 mm). The samples were divided in 4 groups of 5 each: Group 1 samples filled with the composite only; Group 2 samples filled with composite added with SGMFs, Ø1mm (16 spheres for each sample); Group 3 samples filled with composite added with SGMFs, Ø1,5 mm (5 spheres for each sample); Group 4 samples filled with composite added with SGMFs, Ø2 mm (2 spheres for each sample). Digital pictures were taken, in standardized settings, before and immediately after the polymerization of the composite material, placed into the cavities. With a digital image analysis software the distances from the coronal reference points of the cavity walls were measured. Then the difference between the first and second measurement was calculated. The data were analyzed by means of the ANOVA test. Results. A significative reduction on cavity walls deflection, when the composite resin is used in addiction with the SGMFs was observed. The SGMFs of smallest diameter (1mm) showed the better outcome. Conclusion. The SGMFs are reliable in reducing contraction stress in dental composite resins.
Chapter
Narrow-diameter dental implants (NDIs) can be an option to provide minimally invasive implant treatment. NDI applications for replacement of maxillary lateral incisors and mandibular incisors are predictable provided that adequate interproximal (1.5 mm) and facial (2 mm) bone dimensions can be maintained. The main concern with NDIs is that reduced implant diameter will increase the strain on crestal bone with the possibility of mechanical overload and loss of crestal bone and osseointegration. NDIs are appropriate for use where horizontal augmentation procedures would otherwise be needed to augment bucco-lingual ridge width and the patient is unwilling to accept this more invasive and costly approach. Surgical planning requires a minimum facial bone thickness of about 1.5-2 mm or more after osteotomy preparation to promote a stable long-term result. NDIs also may be indicated in situations where bone grafting procedures have previously failed or are at risk of failing because of local site conditions.
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The lack of the available time of professionals involved in the Odontologic field and the difficulty to maintain a good level of information about Oral Implantology, arouse the interest of these authors to expose a synthetic review of 2008 publications in the most relevant dental journals. Inside this article there are different aspects related to treatment planning, special patients, design and surfaces, immediate load, guided bone regeneration, guided tissue regeneration, radiotherapy and extraoral implants.
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Objectives This study aimed to retrospectively investigate the success and survival rates of dental implants used for dentomaxillary prostheses at our hospital and the risk factors associated with large bone defects.Materials and methodsA total of 138 external joint system implants used for dentomaxillary prostheses in 40 patients with large bone defects were included in this study. The alveolar bone at the site of implant insertion was evaluated using panoramic radiography and computed tomography. Various risk factors (demographic characteristics, dental status, and operative factors such as the employment of alveolar bone augmentation, the site, the length, and diameter of implants) for implant failure and complete implant loss were investigated using univariate and multivariate analyses. The associations between the variables and the success and survival rates of dental implants were analyzed using the multivariate Cox proportional hazard models.ResultsThe 10-year overall success and survival rates were 81.3% and 88.4% in this study. Multivariable analysis showed that the male sex (HR 6.22), shorter implants (≤ 8.5 mm) (HR 5.21), and bone augmentation (HR 2.58) were independent predictors of success rate. Bone augmentation (HR 5.14) and narrow implants (≤ 3.3 mm) (HR 3.86) were independent predictors of the survival rate.Conclusion Male sex, shorter or narrow implants, and bone augmentation were independent risk factors for dental implants used in dentomaxillary prostheses in patients with large bone defects.Clinical relevance.Clinicians should consider these risk factors and pay close attention to the management of these patients.
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Mastoid lymph node inflammation is a rare entity. Pathological conditions in the vicinity of the mastoid processes can be challenging for maxillofacial head-neck surgeons to address. We report a case of suppurative mastoid lymphadenitis in an 18-year-old Caucasian male. To our knowledge, there are no publications that highlight the clinical, ultrasonographic, intra-, and postoperative data for any pathologic process that presented as mastoiditis.
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Background/Purpose Crestal bone stability, implant rigidity and occlusal loading are issues with small-diameter implants. This article demonstrates the use of two small-diameter implants replacing a missing wide edentulous site and discusses factors that may affect bone changes. Methods Patients who wanted to restore an edentulous space measuring from 12 to 14 mm wide in the posterior region were offered an alternative treatment option, using two narrow or regular-diameter implants instead of one wide implant. In the study, the crestal bone stability of 12 implants in 6 edentulous sites was assessed by cone beam CTs and periapical radiographs in follow-up visits for up to 4 years. Results The bone level of all the implants was stable at buccal, lingual, mesial and distal sites, with mean values < 1 mm. The average buccal bone thickness was 1.15 ± 1.07 mm and lingual was 1.86 ± 0.89 mm, meaning that implants were surrounded by a sufficient amount of bone. The good treatment outcome may be attributed to the capability of fabricating better emergence profiles, angles (Mean: 20.67 ± 7.82° at the mesial and 20.25 ± 8.23° at the distal site) and cleansable embrasures of prostheses which are key to maintaining good oral hygiene and implant health. Conclusion Using two narrow or regular-diameter implants to replace a single edentulous site measured around 12–14 mm wide in posterior region seemed to be a feasible treatment option. It is especially suitable for sites with ridge atrophy and/or patients suffering from systemic diseases.
Article
Purpose: The aim of the present study was to evaluate the prevalence of some periodontal pathogens in Italian adults with chronic periodontitis. Materials and methods: The sample consisted of 2992 patients with a clinical diagnosis of chronic periodontitis, based on the criteria of the American Academy of Periodontology, sampled in the period 2013-2016: 2108 patients were from Northern, 690 from Central and 194 from Southern Italy. Porphyromonas gengivalis, Treponema denticola, and Tannerella forsythia were investigated in all patients of the present study, while Campylobacter rectus, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans only in 2514 (84%) patients. Subgingival plaque samples of the four sites of greatest probing depth in each patient were used to obtain subgingival microbiota and then processed by quantitative polymerase chain reaction. Results: Periodontal pathogens had the following presence respect to all amount of patients: Aggregatibacter actinomycetemcomitans 16.1%, Campylobacter rectus 73.4%, Fusobacterium nucleatum 93.8%, Porphyromonas gengivalis 65.5%, Treponema denticola 66.4%, and Tannerella forsythia 72.7%. There are no significant statistical differences among geographic areas both for the total bacterial and the single species except for T. Denticola and C. Rectus, which prevalence was significantly higher in Southern Italy (P value <.05). The other investigated species were equally distributed among different regions. A. actinomycetemcomitans was the rarer species detected in this study, while F. nucleatum was the commonest. No differences among areas where observed as regard of the mean bacterial load except for F. Nucleatum whose prevalence in Northern Italy was lower then both in Central and Southern Italy (P value <.05). Conclusions: The results of our study didn't show different geographic distribution of periodontal pathogens among Italian population of the three areas investigated. The homogeneity of the results could be related to genetic and environmental factors.
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Background: Despite the existence of several studies validating the use of narrow diameter implants, most of them are based on pure Ti alloys. There is few clinical evidence of the success of TiZr narrow diameter implants (TiZr NDIs) regarding survival rate (SR) and marginal bone loss (MLB). Purpose: The aim of this review was to systematically assess SR, as well as MBL of TiZr NDIs compared to commercially pure titanium narrow diameter implants (cpTi NDIs). Material and methods: The search was conducted in Medline/PubMed, Cochrane, Scopus, and Embase databases (year 2000 to November 2016). Cohort studies and randomized trials were included. Results: Six clinical studies from the 3453 articles initially identified met the inclusion criteria. There were no statistically significant differences in SR when TiZr NDIs and cpTi NDIs were compared in the 1-year follow up (P = .5), or when comparing TiZr NDIs placed in posterior and anterior regions. There was no difference between groups regarding 1-year SR: -0.01 (95% CI, -0.05-0.03) and MLB: -0.01 mm (95% CI: -0.14-0.12). Conclusion: It can be concluded that TiZr NDIs present similar success rates and peri-implant bone resorption to cpTi NDIs.
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Purpose. The present case report presents the clinical results of delayed expansion of mandibles by ultrasonic surgery in case of mono edentulous. Materials and methods. The patients with a residual alveolar ridge thickness between 2,3 and 4,1 mm in the coronal area of posterior mandible was threated. In the first stage, four linear corticotomies were carried out by ultrasonic surgical device; bone expansion was not performed. After 4 weeks, in the second stage, adequate bone expansion, without compromising cortical vascularisation, by utilising a combination of scalpel, thin chisels and threaded osteotomes was achieved and one implant was placement, after filling the gaps with a cortico bovine biomaterial. Results. The postoperative course was uneventful and final width ridge was 6,17±0,26mm. Conclusions. The present case report showed that mandibular ridge expansion using a delayed split-crest technique by means of ultrasonic surgery and association with biomaterial clinically lead to a good horizontal bone gain with no fractures of the buccal plate and high implant success rate.
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Purpose: The aim of our study is to evaluate the ability of a new type of implant (Konus Implant System®, Industrie biomediche e farmaceutiche, Italy) to isolate the internal of an implant-abutment connection from the external environment. Materials and methods: To identify the capability of the implant to protect the internal space from the external environment, the passage of genetically modified Escherichia coli across implant-abutment interface was evaluated. Implants were immerged in a bacterial culture for twenty-four hours and then bacteria amount was measured inside implant-abutment interface with Real-time PCR. Results: Bacteria were detected inside all studied implants, with a median percentage of 18% for Porphiromonas Gingivalis and 19% for Tannerella Forsythia. Conclusion: The reported results are similar to previous work. Konus Implant System® showed bacterial leakage similar respect others implant systems (18% Porphiromonas Gingivalis, 19% Tannerella Forsitya versus 20% of Bicon© and Ankylos ® systems). In spite of the limits of our study, none two-piece implant system has been demonstrated to perfectly close the gap between implant and abutment.
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Purpose: Different surgical approaches for zygomatic implantology using new designed implants are reported. Material and methods: The surgical technique is described and two cases reported. The zygomatic fixture has a complete extrasinus path in order to preserve the sinus membrane and to avoid any post-surgical sinus sequelae. Results: The surgical procedure allows an optimal position of the implant and consequently an ideal emergence of the fixture on the alveolar crest. Conclusion: The surgical procedures and the zygomatic implant design reduce remarkably the serious post-operative sequelae due to the intrasinus path of the zygomatic fixtures.
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Purpose: The light-emitting diodes (LEDs) have been applied in oral surgery for tissue stimulation and wound healing. Several Authors have highlighted that fibroblasts subjected to phototherapy have an increased viability, proliferation, biomodulation of inflammatory cytokines and genes expression. It remains to be determined which are the best irradiation parameters (energy, wavelength, power) for each type of cell in order to obtain the best bio-stimulation. The aim of this study was to investigate the effects of LED irradiation on primary human gingival fibroblast cells (HGF) on DSP, ELN, HAS1, ELANE, HYAL1, RPL13 genes activation using Real Time PCR. These genes activation is directly connected with elastin protein production and HGF functionality. Materials and methods: Human gingival tissue biopsies were obtained from three healthy patients during extraction of teeth. The gingival pieces were fragmented with a scalpel and transferred in culture dishes for allow the cells growth. Human gingival fibroblasts at the second passage were seeded on multiple 6-well plates and were stimulated with three different light-emitting diodes (LEDs) fixture. After irradiation, the cells were trypsinized, harvested and lysed for RNA extraction. Genes expression was quantified using Real Time PCR. Results: We didn't found significant differences in genes activation of HGF of the three different LEDs. The LED irradiation seems to be directly correlated with the elastin and hyaluronoglucosaminidase 1 genes activation that are directly connected with proteins production and HGF functionality. Conclusions: HGF show an increased deposition of elastin as well as enhanced expression of collagen type I, which is the main protein related to the synthesis and of the collagen-rich matrix.
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Purpose: To present the most frequent occult pathologies unexpectedly encountered via cone-beam computed tomography (CBCT), with particular reference to the diagnostic role of the dentist and that of the radiographer, with a view to clarifying where the diagnostic responsibility lies. Material and methods: A narrative literature review on the most diffused occult pathologies under CBCT was conducted, with iconographical guide as an example for each category. Results: The most frequent forms of unexpected pathologies encountered are: the presence of foreign bodies, airway anomaly, and the presence of radio-opacity or -transparency in the maxillofacial district. Conclusions: The orthodontists must know that they are responsible to recognize these frequent, and potentially serious, pathologies of the head and neck. If the dentist feels unable to take on this responsibility, he or she should, however, be sure to have the scans read by a specialist radiologist.
Article
Purpose To study long‐term function of narrow diameter implants (NDI:s) and if reduced implant‐tooth distance negatively impacts adjacent teeth. Materials and Methods A clinical and radiological follow‐up of NDI:s replacing maxillary laterals and mandibular incisors was performed. Subjects that received 3.0‐3.3 mm‐diameter single implants from 3 units in Uppsala and Västerås, Sweden, between 2002 and 2011 were offered to participate in this retrospective study. Results Twenty‐seven patients (30 implants) underwent clinical and CBCT examination, mean follow‐up time was 63.3 months. On average, the implant‐tooth distance was 1.6 mm at the cervical region and 17 implants were placed 1 mm or less to the adjacent root. Additionally, 2 patients (3 implants) underwent clinical examination (I). Twenty‐seven patients (36 implants) declined the examination but agreed to an interview (II). At the time of the follow‐up, all implants had good function, and implant survival of group I and II together was 97.2%. In both groups, the 2 main patient concerns were discoloration and regression of the buccal gingiva. Conclusion Survival of implants is in accordance to standard diameter studies and although most implants were placed very close to the adjacent teeth, no pathologies could be linked to this except aesthetic concerns.
Article
Dental implants are popular for dental rehabilitation after tooth loss. The goal of this systematic review was to assess bone changes around bone-level and tissue-level implants and the possible causes. Electronic searches of PubMed, Google Scholar, Scopus, and Web of Science, and a hand search limited to English language clinical trials were performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines up to September 2020. Studies that stated the type of implants used, and that reported bone-level changes after insertion met the inclusion criteria. The risk of bias was also evaluated. A total of 38 studies were included. Eighteen studies only used bone-level implants, 10 utilized tissue-level designs and 10 observed bone-level changes in both types of implants. Based on bias assessments, evaluating the risk of bias was not applicable in most studies. There are vast differences in methodologies, follow-ups, and multifactorial characteristics of bone loss around implants, which makes direct comparison impossible. Therefore, further well-structured studies are needed.
Article
Statement of problem Patients diagnosed with a cleft palate often have a congenitally missing maxillary lateral incisor. The congenital cleft presents the practitioner with challenges including the quantity and quality of bone, a surgically managed cleft correction, and limited clinical space. Purpose The purpose of the present prospective investigation was to report preliminary results at the 1-year follow-up for this planned 5-year investigation of narrow diameter implants used to restore a missing lateral incisor in patients with a cleft palate. Material and methods Fourteen study participants with a cleft palate and a missing maxillary lateral incisor were enrolled based on established criteria. Narrow diameter implants (AstraTech OsseoSpeed TX 3.0S and 3.5 mm) were placed by using a 2-stage protocol and restored. All study participants received an Atlantis abutment and a cement-retained crown. Four probing depth measurements and bleeding on probing were measured at baseline and at 1 year. Probing depth measurements were evaluated using a 2-way repeated measures ANOVA with Tukey-Kramer multiple comparisons tests. Radiographic marginal bone loss was measured at 1-year by using a digital subtraction technique and evaluated by using a repeated measures ANOVA. Pretreatment cone beam computed tomography (CBCT) images were used to measure a mean gray level that was proportional to bone mineral density (BMD) in the implant site. One-way mixed ANOVA was used to compare the mean gray level and average implant stability quotient (ISQ) loading. A Pearson correlation was also tested between those parameters (α=.05) for each statistical analysis. Results The mean marginal bone loss at 1 year was 0.601 ±0.48 mm. Regarding probing depth measurements, a 2-way repeated measures ANOVA found both the location (P=.012) and time (P=.009) were significant. The Tukey-Kramer multiple comparisons test showed a significant difference between the buccal and distal site (P=.006) from baseline to 1-year follow-up. Conclusions Narrow diameter implants are a reliable treatment for replacing a missing lateral incisor in patients with a cleft palate at 1 year, with an implant survival rate of 100% and implant success rate of 94% using the established criteria. A negative association was found between the bone mineral density and the implant stability in the alveolar cleft site of a patient with a cleft palate. The peri-implant soft tissue probe depths exhibited significant change during the first year.
Article
Edentulous sites are often characterized by inadequate bone volume for dental implant therapy. Bone augmentation procedures for site development involve longer healing period and are often invasive, costly, and associated with postoperative morbidity. This article discusses alternatives to invasive bone grafting procedures that are often used to develop implant sites. Owing to the broad nature of this topic, it is presented in two articles. In part I, the use of short and narrow-diameter implants are discussed. Part II reviews the use of tilted as well as fewer implants to support a prosthesis.
Article
Purpose: To propose a length-and-diameter-based classification scheme for dental implants to standardize terminology in the dental literature and communication between interested parties. Materials and methods: This study was mainly based on searching two major resources: published scientific research papers and 14 of the most popular dental implant manufacturers. Indexed databases were searched from January 2004 up to and including February 2016 using the keywords "dental implant length" and "dental implant diameter." Retrieved titles and abstracts were screened, and related full-text articles were reviewed. Full-text articles that clearly stated the terms and measurements of implants used were included and considered for proposing this classification scheme. Results: The initial search for implant diameter and length yielded 1007 and 936 articles, respectively. A total of 85 studies (41 about diameter, 44 about length) were selected and reviewed. The remaining studies (966 about diameter, 892 about length) that did not abide by the eligibility criteria were excluded. The terms "long," "short," "standard," "wide," and "narrow" were the most commonly used terms in the literature. A classification scheme for implants by diameter and length was proposed. Conclusions: Indexed publications contain a variety of terms used by authors to describe diameter and length of dental implants without conformity and standardization. The classification scheme proposed in this article could serve as a reference for interested parties.
Full-text available
Article
Criteria for the evaluation of dental implant success are proposed. These criteria are applied in an assessment of the long-term efficacy of currently used dental implants including the subperiosteal implant, the vitreous carbon implant, the blade-vent implant, the single-crystal sapphire implant, the Tübingen implant, the TCP-implant, the TPS-screw, the ITI hollow-cylinder implant, the IMZ dental implant, the Core-Vent titanium alloy implant, the transosteal mandibular staple bone plate, and the Brånemark osseointegrated titanium implant. An attempt has been made to standardize the basis for comments on each type of implant.
Full-text available
Article
A study involving the immediate loading of Brånemark implants in the edentulous mandibles of 10 patients is reported. The design involved the immediate loading of four widely distributed implants with a transitional fixed implant-supported prosthesis at first-stage surgery, avoiding the need for a removable prosthesis. A sufficient number of additional implants are allowed to heal in the conventional manner to provide sufficient support for a definitive fixed prosthesis even if all of the immediately loaded implants fail. Preliminary results have been favorable, with all patients functioning with a fixed implant prosthesis from the day of first-stage surgery.
Full-text available
Article
A clinical and radiographical study was performed to compare the outcome of oral rehabilitation in the edentulous mandible by fixed supraconstructions connected to implants installed according to either i) a 1-stage surgical procedure and immediate loading (Experimental Group-EG), or ii) the original 2-stage concept (Reference Group-RG). The EG comprised 16 subjects with edentulous mandibles. Beyond the non-smoking criteria the following specific inclusion criteria were adopted: i) all patients had to consider themselves to be in good general health, ii) the amount of bone had to enable the installation of 5-6, at least 10 mm long fixtures to be bicortically anchored (Mk II fixtures; Nobel Biocare AB, Göteborg, Sweden) between the mental foramina, and iii) the patients had to be available for the follow-up and maintenance programme. A total of 88 implants were placed in the EG (16 patients) compared to 30 in the RG (11 patients). In the EG, fixed appliances were connected to the implants within 20 days following implant installation while the fixed appliances in the RG were connected about 4 months following fixture installation. At the time for delivery of the supraconstructions all 27 patients were radiographically examined, an examination that was repeated at the 18-month follow-up. The analysis of the radiographs from the EG disclosed that during the 18-month observation period the mean loss of bone support amounted to 0.4 mm. The corresponding value observed in the RG was 0.8 mm. During the 18-month observation period no fixture was lost in any of the 2 groups examined. The implants under study as well as those in the reference material were at all observation intervals found to be clinically stable. The present clinical study demonstrated that it is, at least based on an 18-month observation period, possible to successfully load titanium dental implants immediately following installation via a permanent fixed rigid cross-arch supraconstruction. However, such a treatment approach has so far to be strictly limited to the inter-foramina area of the edentulous mandible.
Full-text available
Article
Placement of small-diameter implants often provides a solution to space-related problems in implant restoration. This 7-year retrospective study presents results from 192 small-diameter implants placed in 165 patients from 1992 to 1996. The dental records of each patient were reviewed. The implants, which were either 2.9 mm or 3.25 mm in diameter, were placed by 2 different surgeons. All prosthetic appliances were fabricated by the same prosthodontist. Ninety-four implants supported single-tooth cemented restorations; the remaining 98 implants supported cemented or screw-retained partial prostheses. The total implant survival rate was 95.3%. Four implants were lost at second-stage surgery, and 5 more were lost after loading. Small-diameter implants demonstrated a survival rate similar to those reported in previous studies of standard-size implants. The results suggest that small-diameter implants can be successfully included in implant treatment. They may be preferable in cases where space is limited.
Article
A clinical and radiographical study was performed to compare the out‐come of oral rehabilitation in the edentulous mandible by fixed supra‐constructions connected to implants installed according to either i) a l‐stage surgical procedure and immediate loading (Experimental Group ‐EG), or ii) the original 2‐stage concept (Reference Group ‐ RG). The EG comprised 16 subjects with edentulous mandibles. Beyond the non‐smoking criteria the following specific inclusion criteria were adopted: i) all patients had to consider themselves to be in good general health, ii( the amount of bone had to enable the installation of 5‐6, at least 10 mm long fixtures to be bicortically anchored (Mk II fixtures; Nobel Biocare AB, Goteborg, Sweden) between the mental foramina, and iii) the patients had to be available for the follow‐up and maintenance programme. A total of 88 implants were placed in the EG (16 patients) compared to 30 in the RG (11 patients). In the EG, fixed appliances were connected to the implants within 20 days following implant installation while the fixed appliances in the RG were connected about 4 months following fixture installation. At the time for delivery of the supraconstructions all 27 patients were radiographically examined, an examination that was repeated at the 18‐month follow‐up. The analysis of the radiographs from the EG disclosed that during the 18‐month observation period the mean loss of bone support amounted to 0.4 mm. The corresponding value observed in the RG was 0.8 mm. During the 18‐month observation period no fixture was lost in any of the 2 groups examined. The implants under study as well as those in the reference material were at all observation intervals found to be clinically stable. The present clinical study demonstrated that it is, at least based on an 18‐month observation period, possible to successfully load titanium dental implants immediately following installation via a permanent fixed rigid cross‐arch supraconstruction. However, such a treatment approach has so far to be strictly limited to the interforamina area of the edentulous mandible.
Article
Screw-shaped implants with 3 different surface topographies, evidenced visually as well as numerically with an optical profilometer. were inserted in rabbit bone. After a healing period of 12 weeks, a statistically significant higher removal torque was needed to unscrew screws blasted with25 μm TiO2 particles and screws blasted with 75 μm particles of A1203 compared with screws with a turned surface. The histomorphometric evaluation demonstrated a higher percentage of bone-to-metal contact for implants blasted with 25 μm particles of TiO2 compared with the as-machined implants. A greater surface area of bone in threads was found for the turned screws compared with screws blasted with 25 μm TiO2 particles. In the short-term follow-up, there was a better fixation of implants with an average surface roughness of 0.9–1.3 μm and with a homogeneous surface structure than of implants with an average surface roughness of 0.4 μm and with a clear direction of the surface pattern.
Article
The choice of implant diameter depends on the type of edentulousness, the volume of the residual bone, the amount of space available for the prosthetic reconstruction, the emergence profile, and the type of occlusion. Small-diameter implants are indicated in specific clinical situations, for example, where there is reduced interradicular bone or a thin alveolar crest, and for the replacement of teeth with small cervical diameter. Before using a small-diameter implant, the biomechanical risk factors must be carefully analyzed. Preliminary reports of this type of implant show good short- and medium-term results. CLINICAL SIGNIFICANCE Specific clinical situations indicate the use of small-diameter implants: a reduced amount of bone (thin alveolar crest) and where the replacement tooth requires a small cervical diameter. In some cases, the use of small-diameter implants avoids bone reconstruction.
Article
To compare different surgical insertion procedures, histologic and histometric studies were made on the structure of the interface between jaw bone and implants in two monkeys. Two materials were tested; TiO2 coated and noncoated, screw-type titanium alloy endosseous implants. All implants by tapping insertion were healed with direct bone apposition whereas implants by nontapping insertion revealed some degrees of fibrous connective tissue intervention between bone and implant. No difference was found between TiO2 coated and non-coated materials.
Article
The clinical requirements that led to the development of the new ITI implant concept are discussed. This concept consists of a system of one- and two-part hollow-cylinder and hollow-screw implants and is characterized by a wide range of indications. The one-part implants are intended for use in edentulous mandibles as retentive anchors for bar-type overdenture reconstruction. The two-part implants are intended for use in partially edentulous jaws as abutments for fixed prosthesis reconstructions. The clinical aspects of the new ITI implants are discussed and documented by case examples and early clinical results.
Article
The Titanium Plasma-Sprayed Swiss Screw Implant System is described, with a discussion of preoperative patient evaluation, and implantation and prosthetic techniques. The results in 484 patients in whom these implants were placed in four countries are summarized.
Article
In vivo temperature measurements were performed at drilling in the femoral cortex of the rabbit, dog and man. In the clinical study the bone temperature was measured at fixation of a Richards plate to stabilize a pertrochanteric fracture. With a drill speed of around 20 000 rpm and saline cooling, temperatures of 40 degrees C in rabbits, 56 degrees C in dogs and 89 degrees C in patients were recorded at a distance of 0.5 mm from the periphery of the drill hole. The difference in temperature between the animal and clinical studies was mainly attributed to the difference in cortical thickness between the species. When drilling straight through the canine femur from the lateral to the medial side, a 9 degrees C higher temperature was measured in the remote, medial cortex compared to that recorded in the lateral cortex. This difference arose because it is difficult for the cooling agent to reach the medial cortex. The results of the present study indicate that temperatures measured in animal experiments are not applicable to the clinical situation where very high temperatures may arise on drilling in cortical bone, even if saline cooling is used.
Article
Osseointegration implies a firm, direct and lasting connection between vital bone and screw-shaped titanium implants of defined finish and geometry-fixtures. Thus, there is no interposed tissue between fixture and bone. Osseointegration can only be achieved and maintained by a gentle surgical installation technique, a long healing time and a proper stress distribution when in function. During a 15-year period (1965-1980), 2768 fixtures were installed in 410 edentulous jaws of 371 consecutive patients. All patients were provided with facultatively removable bridges and were examined at continuous yearly controls. The surgical and prosthetic technique was developed and evaluated over a pilot period of 5 years. The results of standardized procedures applied on a consecutive clinical material with an observation time of 5-9 years were thought to properly reflect the potential of the method. In this group, 130 jaws were provided with 895 fixtures, and of these 81% of the maxillary and 91% of the mandibular fixtures remained stable, supporting bridges. In 89% of the maxillary and 100% of the mandibular cases, the bridges were continuously stable. During healing and the first year after connection of the bridge, the mean value for marginal bone loss was 1.5 mm. Thereafter only 0.1 mm was lost annually. The clinical results achieved with bridges on osseointegrated fixtures fulfill and exceed the demands set by the 1978 Harvard Conference on successful dental implantation procedures.
Article
Screw-shaped implants with 3 different surface topographies, evidenced visually as well as numerically with an optical profilometer, were inserted in rabbit bone. After a healing period of 12 weeks, a statistically significant higher removal torque was needed to unscrew screws blasted with 25-microns TiO2 particles and screws blasted with 75-microns particles of AI2O3 compared with screws with a turned surface. The histomorphometric evaluation demonstrated a higher percentage of bone-to-metal contact for implants blasted with 25-microns particles of TiO2 compared with the as-machined implants. A greater surface area of bone in threads was found for the turned screws compared with screws blasted with 25-microns TiO2 particles. In the short-term follow-up, there was a better fixation of implants with an average surface roughness of 0.9-1.3-microns and with a homogeneous surface structure than of implants with an average surface roughness of 0.4 microns and with a clear direction of the surface pattern.
Article
A load-free healing period has been advocated as a prerequisite to achieving osseointegration. This article reports two cases in which immediate loading of a specially designated additional, or "expendable," set of titanium root-form implants was successfully utilized to support provisional fixed restorations in the maxilla and the mandible. This immediate-loading protocol is suggested as a reliable adjunctive therapeutic modality for offering implant patients access to fixed interim restorations during the healing phase of the primary fixtures. Another advantage of this approach is that it provides protection from potential transmucosal overload of the primary implants as well as any sites undergoing osseous regenerative procedures.
Article
Immediate loading of threaded implants with a fixed provisional restoration at stage 1 surgery was evaluated in 10 consecutive patients. The patients selected had to be completely edentulous and have adequate bone for a minimum of 10-mm-long implants. A minimum of 10 implants were placed in each patient's arch. A minimum of five implants were submerged initially for medicolegal reasons and allowed to heal without loading. The remaining implants were loaded the day of stage 1 surgery. Once the provisional restoration was relined, it was cemented or screw retained. A total of 107 implants were placed in these 10 patients; 6 had them placed in the mandible, and 4 in the maxilla. Six patients were treated with Nobel Biocare implants, one with ITI Bonefit implants, two with Astra Tech TiOblast implants, and one with a 31 implant. Sixty-seven of 69 implants that were loaded integrated, and 37 of 38 submerged implants integrated. All 10 patients have been restored with a definitive prosthesis, and all had a fixed provisional prosthesis from stage 1 surgery. The results of this study indicate that immediate loading of multiple implants rigidly splinted around a completely edentulous arch can be a viable treatment modality.
Article
THIS STUDY REPORTS ON THE histological findings of two immediately loaded titanium plasma-sprayed (TPS) implants, retrieved for a fracture of the abutment and for psychological reasons, after 8 and 9 months of loading, respectively. The microscopical analysis showed that mature, compact, cortical bone was present around both implants, with the bone implant contact percentage about 60 to 70%. No fibrous tissue or gaps were present at the interface. No resorption was present in the peri-implant bone. On both implants a few osteoblasts were found positive at the interface for alkaline phosphatase (ALP); while no cells positive for acid phosphatase (ACP) were present. Immediate loading can, perhaps, be used in very selected cases of good bone quality, with implants that have certain macro- (screw shape) and micro-interlocks (titanium plasma-sprayed surface) characteristics. Good results have been reported also for non-TPS surface (e.g., machined surface). More data about different designs (e.g., cylinders) or coatings (e.g., hydroxyapatite) are needed before any firm conclusions about immediate loading can be reached.
Article
Placement of small diameter implants often provides a solution to space problems in implant restoration. Analysis of the success of this type of implant restoration has not been clearly determined. This 5-year retrospective study presents results from 52 mini-implants for single-tooth restorations placed in 44 patients from 1992 to 1994. Dental records of 44 patients with 52 mini-implants placed during 1992-94 were reviewed. The implants were all placed by the same surgeon and the single-tooth custom screwed posts with cemented crowns were positioned on the implants by the same prosthodontist. The results achieved by the mini-implant rehabilitation were similar to those reported for standard single-tooth implant restoration. Total implant survival rate was 94.2%. Two implants were lost at second stage surgery, and another was lost after temporary loading. The results suggest that single-tooth mini-implant restoration can be a successful treatment alternative to solve both functional and esthetic problems. They may represent the preferred choice in cases where space problems limit the use of standard or wide diameter implants.
Article
A prospective study was conducted on 13 consecutive patients who received immediately loaded mandibular fixed-implant prostheses. The exclusion criteria were 1) general: heavy smoking, demonstrated bruxism, or general ill health and 2) local: lesions in the bone area to be implanted or inadequate morphology requiring augmentation techniques. After suturing the surgical wounds, impressions were taken, and transitional prostheses were screwed in within 2 weeks of surgery. A total of 61 implants of four different designs were placed. Thirty-two of the implants were placed at the same time as performing the extractions of the residual dentition. In 13 of the implants, there was a 2-month period between extraction surgery and implantation. The other 16 implants were inserted in alveolar bone that had been edentulous for more than 12 months. Despite these differences, all 61 implants were immediately loaded. Parallel x-rays were taken of the 13 patients at the time of transitional prosthesis placement, at the time of definite prosthesis placement, and 6 months later at the first control. During the 18-month follow-up period, two implants failed, and the remaining 59 implants were found to be clinically immobile, asymptomatic, and free of any radiolucency, giving a survival rate of 96.7%. Analysis of radiographic bone levels gives us a cumulative success rate of 93.4%. These figures are comparable to those obtained in similar studies and are no different than those from implant prostheses loaded in the conventional delayed manner. Based on these preliminary results, we can conclude that the immediate loading of mandibular implants is a viable and efficient approach.
Article
The Brånemark System Classic is well documented for its successful and predictable results in dental implant rehabilitation. However, the classic two-stage protocol is associated with problems, such as long treatment time and high treatment cost. To overcome these problems, new developments, including early functional loading protocol and Brånemark System Novum, have been introduced by various groups of researchers. In Hong Kong, a protocol has been developed to immediately load the Brånemark System fixtures with a fixed provisional prosthesis. The goal of this prospective study was to present the Hong Kong Bridge protocol and report the short-term evaluation of this protocol in a group of patients who had undergone dental implant treatment for their edentulous mandibles. Twenty-seven consecutive patients being treated at the Hong Kong Osseointegration Implant Centre between June 1998 and December 2000 were included in this study. A total of 123 Brånemark System fixtures were installed and regularly followed up for 3 to 30 months. The prosthesis stability and the marginal bone level were regularly evaluated clinically and radiographically, respectively, after the implant surgery. Fifteen of the 27 patients had been followed up for 1 year or longer. Two patients with eight fixtures were withdrawn from the study. Two of the 115 remaining fixtures failed, resulting in an overall implant survival rate of 98.3%. The mean marginal bone change was reported on 49 fixtures that had passed the 1-year review. The mean marginal bone loss was 0.60 mm (p < .05) after 1 year of functional loading. To load the mandibular Brånemark System fixtures immediately according to the Hong Kong Bridge protocol was a predictable and simple method with good results during this preliminary study period.
Article
The aim of this study was the evaluation, from a clinical point of view, of implants subjected to immediate functional loading (IFL) and to immediate non-functional loading (INFL) in various anatomical configurations. The study included 152 patients who had given their informed consent. A total of 646 implants were inserted. The implants were placed in 39 totally edentulous mandibles, 14 edentulous maxillae, 23 edentulous posterior mandibles, 16 edentulous anterior mandibles, 16 edentulous anterior maxillae, and 15 edentulous posterior maxillae. Fifty-eight implants were used to replace single missing teeth. In 65 cases, IFL was carried out for 422 implants. INFL was carried out in 116 cases, (224 implants). In the IFL group 6 of 422 implants failed (1.4%); in the INFL group 2 of 224 implants failed (0.9%). All the other implants appeared, from clinical and radiographic observations, to have successfully osseointegrated and have been functioning satisfactorily since insertion. All failures were observed in the first few months after implant loading. Immediate functional and non-functional loading seems to be a technique that gives satisfactory results in selected cases.
Article
Immediate/early loading protocols are becoming frequently used in implant dentistry, but the prerequisites for achieving good results and the limitations of such protocols are not fully known. Moreover, the terminology used in immediate/early loading is still confusing. The purpose of this article is to present the outcome of a consensus meeting on immediate/early loading. A consensus meeting was organized during the Sociedad Española de Implantes World Congress in Barcelona on May 23, 2002, with the objective to present and discuss the experiences from immediate/early loading protocols in dental implant treatment. The purpose was also to discuss definitions of the terminology used in immediate/early loading. The consensus meeting agenda included presentations from invited experts, followed by a consensus discussion. A consensus statement was agreed on. Multiple independent investigators have demonstrated that immediate/early loading of implants is possible in many clinical situations; however, additional documentation is required.
Article
Background: Implant dentistry has become successful with the discovery of the biological properties of titanium. In the original protocol, studies have advocated a 2-stage surgical protocol for load-free and submerged healing to ensure predictable osseointegration. However, the discomfort, inconvenience, and anxiety associated with waiting period remains a challenge to both patients and clinicians. Hence, loading implant right after placement was attempted and has gained popularity among clinicians. Issues/questions related to this approach remain unanswered. Therefore, it is the purpose of this review article to (1). review and analyze critically the current available literature in the field of immediate implant loading and (2). discuss, based on scientific evidence, factors that may influence this treatment modality. Material and methods: Literature published over the past 20 years was selected and reviewed. Findings from these studies were discussed and summarized in the tables. The advantages and disadvantages associated with immediate implant loading were analyzed. Factors that may influence the success of immediate implant loading, including patient selection, type of bone quality, required implant length, micro- and macrostructure of the implant, surgical skill, need for achieving primary stability/control of occlusal force, and prosthesis guidelines, were thoroughly reviewed and discussed. Results and conclusion: Various studies have demonstrated the feasibility and predictability of this technique. However, most of these articles are based on retrospective data or uncontrolled cases. Randomized, prospective, parallel-armed longitudinal human trials are primarily based on short-term results and long-term follow-ups are still scarce in this field. Nonetheless, from available literature, it may be concluded that anatomic locations, implant designs, and restricted prosthetic guidelines are key to ensure successful outcomes. Future studies, preferably randomized, prospective longitudinal studies, are certainly needed before this approach can be widely used.
Article
The biofilm that forms and remains on tooth surfaces is the main etiological factor in caries and periodontal disease. Prevention of caries and periodontal disease must be based on means that counteract this bacterial plaque. To monitor the incidence of tooth loss, caries and attachment loss during a 30-year period in a group of adults who maintained a carefully managed plaque control program. In addition, a comparison was made regarding the oral health status of individuals who, in 1972 and 2002, were 51-65 years old. In 1971 and 1972, more than 550 subjects were recruited. Three hundred and seventy-five subjects formed a test group and 180 a control group. After 6 years of monitoring, the control group was discontinued but the participants in the test group was maintained in the preventive program and was finally re-examined after 30 years. The following variables were studied at Baseline and after 3, 6, 15 and 30 years: plaque, caries, probing pocket depth, probing attachment level and CPITN. Each patient was given a detailed case presentation and education in self-diagnosis. Once every 2 months during the first 2 years, once every 3-12 months during years 3-30, the participants received, on an individual need basis, additional education in self-diagnosis and self-care focused on proper plaque control measures, including the use of toothbrushes and interdental cleaning devices (brush, dental tape, toothpick). The prophylactic sessions that were handled by a dental hygienist also included (i) plaque disclosure and (ii) professional mechanical tooth cleaning including the use of a fluoride-containing dentifrice/paste. Few teeth were lost during the 30 years of maintenance; 0.4-1.8 in different age cohorts. The main reason for tooth loss was root fracture; only 21 teeth were lost because of progressive periodontitis or caries. The mean number of new caries lesions was 1.2, 1.7 and 2.1 in the three groups. About 80% of the lesions were classified as recurrent caries. Most sites, buccal sites being the exception, exhibited no sign of attachment loss. Further, on approximal surfaces there was some gain of attachment between 1972 and 2002 in all age groups. The present study reported on the 30-year outcome of preventive dental treatment in a group of carefully monitored subjects who on a regular basis were encouraged, but also enjoyed and recognized the benefit of, maintaining a high standard of oral hygiene. The incidence of caries and periodontal disease as well as tooth mortality in this subject sample was very small. Since all preventive and treatment efforts during the 30 years were delivered in one private dental office, caution must be exercised when comparisons are made with longitudinal studies that present oral disease data from randomly selected subject samples.
Article
The aim of this study was to clinically evaluate immediate functionally loaded (IFL) and immediate nonfunctionally loaded (INFL) implants for various indications compared to a control group with a conventional healing period. Two hundred fifty-three patients took part in the study. A total of 702 XiVE implants (Dentsply/Friadent, Mannheim, Germany) were placed: 253 IFL implants, 135 INFL implants, and 314 controls. In each of the 3 groups, 2 implants failed. For all the other implants involved, from a clinical and radiographic point of view, osseointegration was successful. As long as the prerequisites are fulfilled, immediate functional loading and immediate nonfunctional loading are predictable techniques, not only in completely edentulous patients but also in partially edentulous patients. Immediate functional loading and immediate nonfunctional loading appear to be techniques that can provide satisfactory implant success rates in selected cases.
Article
Alveloar ridges of limited dimensions could preclude the placement of dental implants of the regular dimension. Smaller diameter implants - narrow platform (NP) implants were commercially available to address this issue. The aim of the study was to determine the 5-year clinical performance of 3.3 mm diameter NP implants. Twenty-three machined screw-shaped NP implants were placed in nine patients (six males; three females) between 18 and 70 years of age. Clinical and radiographic examinations were performed annually for 5 years. Recognized implant success criteria was used. The criteria were based on the mean marginal alveolar bone loss, the placement of prosthesis of satisfactory appearance, and the absence of implant mobility, peri-implant radiolucency, pain, discomfort or infection. One implant failed at abutment connection. The remaining 22 implants were restored and functioned successfully according to the criteria. The mean marginal alveolar bone loss during the first year was 0.41 +/- 0.17 mm. The mean marginal alveolar bone loss between the second and fifth year was 0.03 +/- 0.06 mm. The success rate of NP implants according to a well-established set of criteria was 96%.
Article
Dental implants with a reduced diameter are designed for specific clinical situations, such as placement of implants where bone width is narrow or between adjacent teeth that have only a narrow space between them. They are particularly useful when replacing small teeth such as lateral maxillary and mandibular incisors. The aim of the present study was the clinical evaluation of 2-part ITI implants (full-body screws with a 3.3-mm diameter). One hundred forty-nine partially or completely edentulous patients received a total of 298 2-part ITI implants over a 10-year period. After a standard healing period (3 to 6 months), the implants were restored with fixed restorations such as single crowns or fixed partial or complete prostheses or overdentures. Complete prosthesis or overdenture in the edentulous jaw was the predominant type of restoration. All patients followed a strict maintenance program, with regular recalls at least once a year. The survival rate of the implants was analyzed, and prosthetic complications were assessed. Three implants were lost during the healing phase on account of peri-implant infection. Two implant body fractures with an osseous length of 8 mm were observed (one after 2 years of observation, the other after 6 years). Four implants exhibited transient peri-implant inflammation that was treated successfully by interceptive therapy. The cumulative 5-year survival rate of the implants was 98.7% (96.6% after 6 years). Prosthetic complications were mostly limited to loose occlusal screws and sore spots caused by the denture base. Within the limited observation period, failures of small-diameter implants were infrequent. Prosthetic complications were not dependent on the use of small-diameter implants. The use of 3.3-mm ITI implants appears to be predictable if clinical guidelines are followed and appropriate prosthetic restorations are provided. However, fatigue fracture may occur after a long period of function.
Article
Immediate functional loading is a new surgical-prosthetic technique that can be used extensively in implant placement. Because of a lack of experimental reports regarding edentulous maxilla, we decided to evaluate the survival rate of immediately loaded dental implants in this area. Forty-three patients (44.4% male) with a median age of 55 years receiving 388 implants (mean 9.0 per case) were enrolled in this study. Cross-arch acrylic provisional restorations were performed in the same stage. Data were analyzed by Kaplan-Meier product limit estimation. Stratification of implants survival was performed for the available variables of interest, and comparisons were analyzed by a log rank test. Cox algorithm was used for multivariable analysis. At 5-year follow-up, the crude survival rate (overall survival not stratified according to any available variable) was 98%. All failures occurred within 6 months from loading. We found differences in survival relating to: 1) implant diameter (99.37% for diameter < or =5.25 mm and 93.75% for diameter >5.25 mm); 2) number of implants (99.29% for < or =10 implants and 96.30% for >10); and 3) gender (97.08% and 99.54% for males and females, respectively). Cox regression analysis showed that diameter of implants adjusted for patient age and gender was associated to an average risk of failure (hazard rate) of 3.13 (P value = 0.042, 95% confidence interval 1.04 to 9.43) per mm (from 3 to 6.5). Immediate functional loading is a reliable surgical-prosthetic procedure in edentulous maxillae. Implants with wider diameter are associated with a higher risk of failure.
Article
The advantages of placing implants in fresh extraction sockets and putting them in immediate/early function are many. A predicable protocol opens the possibility of performing a single surgical procedure, giving the patient a temporary prosthesis immediately, and minimizing the shrinkage of hard tissue and soft tissue recession. The aim of the present study was to develop a strict protocol for and to evaluate the feasibility of immediate/ early function on implants placed in fresh extraction sockets located in maxillae and posterior mandibles, including defects around the implants treated according to a regenerative procedure. Nineteen patients were treated after tooth extraction according to an immediate function protocol and were observed for 18 months. Fifty Mk IV TiUnite (Nobel Biocare AB, Göteborg, Sweden) implants were installed in partially edentulous areas in maxillae (n = 17) and posterior mandibles (n = 5). Implants were installed directly into the alveoli, and the temporary prostheses were connected immediately after surgery (n = 11) or within 7 days, that is, an "early function" procedure (n = 11). Thirteen implants did not require any type of regenerative procedure, whereas the remaining 37 implants had filling with autogenous bone, 4 of which also had a resorbable membrane. Standardized intraoral radiographs were taken for evaluation of marginal bone level, and 38 of the implants were systematically checked by resonance frequency analysis. All patients were followed for 18 months, and none of the 50 implants failed. However, one implant showed signs of failure after 6 weeks, but once the occlusal load was removed, the implant regained its stability completely, no longer demonstrated symptoms, and could be used successfully for prosthetic rehabilitation. The mean value of the implant stability quotient was 60 at baseline (range 45-75) and 63 after 6 months (range 46-75). The marginal bone resorption was 0.9 mm (SD 1.1 mm; n = 48) 18 months after implant insertion (1 year after final prosthesis). The immediate placement of implants into fresh extraction sockets combined with immediate/early function procedures seems to be a safe and reliable procedure when using a strict protocol.
Article
Infection in tooth extraction sites has traditionally been considered an indication to postpone implant insertion until the infection has been resolved. The aim of this study was to evaluate the survival rate of early-loaded implants placed immediately after extraction of teeth with endodontic and periodontal lesions in the mandible. Twenty patients in need of mandibular implant treatment and with teeth showing signs of infection in the interforaminal area were included in the study. The patients received four to six implants (Brånemark System, Nobel Biocare AB, Göteborg, Sweden) in or close to the fresh extraction sockets and received a provisional prosthesis within 3 days. Final prostheses were delivered after 3 to 12 months. The surgical protocol paid special attention to the preservation of high implant stability and control of the inflammatory response. The patients were followed up for 15 to 44 months. No implants were lost, resulting in a 100% survival rate. A mean marginal bone loss of 0.7 mm (SD 1.2 mm) was registered during the observation period. No signs of infection around the implants were detected at any follow-up visit. A high survival rate can be achieved for immediately placed and early-loaded implants in the mandible despite the presence of infection at the extracted teeth.
Non-functional immediate teeth in partially edentulous patients: A pilot study of 10 consecutive cases using the Maestro Dental Implant System
  • Ce Misch
Misch CE. Non-functional immediate teeth in partially edentulous patients: A pilot study of 10 consecutive cases using the Maestro Dental Implant System. Com-pendium 1998;19:25-36.