K A Hiller

Universität Regensburg, Regensburg, Bavaria, Germany

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Publications (52)120.46 Total impact

  • Article: Establishment of an optimized ex vivo system for artificial root canal infection evaluated by use of sodium hypochlorite and the photodynamic therapy.
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    ABSTRACT: AIM: To establish a refined model of artificially infected root canals and confirm its suitability as a sensitive ex vivo method to assess the efficacy of disinfecting agents. Disinfection was evaluated using sodium hypochlorite (NaOCl), either blocked or unblocked by sodium thiosulphate, and a recently promoted method of disinfection, the antibacterial photodynamic therapy (PDT). METHODOLOGY: The roots of bovine incisors were sectioned into three parts, the canals of coronal and middle regions were filled with a suspension of Enterococcus faecalis and the apical region with culture medium. After 7 days, coronal sections were disinfected using NaOCl (0.5%, 1.0% and 3.0% for 30, 60 and 600 s) or a system for photoactivated chemotherapy (PACT; Cumdente, Tübingen, Germany) for antibacterial PDT. Apical sections served as sterile controls and middle sections as bacterial growth controls. In half of the NaOCl-treated specimens, disinfection was arrested. Dentine chips from biopsies at different depths from the central canal towards the periphery were plated and assessed for colony-forming units (CFU). Disinfection was considered biologically relevant if the reduction of CFU was at least three log(10) orders of magnitude. RESULTS: Colony-forming units of 10(3) -10(4) in growth controls indicated effective artificial infection. A biologically relevant reduction of CFU was accomplished with unblocked NaOCl, but not after blocking with NaOCl nor with PDT. CONCLUSIONS: The system reliably detected disinfection of the root canal and dentinal tubules and proved suitable for ex vivo testing of root canal disinfection. The effect of NaOCl depended on the duration of impact. Under the present experimental conditions, the antibacterial PDT system did not achieve sufficient disinfection.
    International Endodontic Journal 09/2012; · 2.18 Impact Factor
  • Article: TEGDMA reduces mineralization in dental pulp cells.
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    ABSTRACT: Direct application of dentin bonding agents onto the exposed pulp has been advocated, but in vivo studies indicate a lack of reparative dentin formation. Our objective was to investigate the role of triethylene glycol dimethacrylate (TEGDMA), a commonly used compound in dentin bonding agents, as a potential inhibitor of mineralization. Human pulp cells were exposed to different concentrations of TEGDMA, and expression of the mineralization-related genes collagen I, alkaline phosphatase, bone sialoprotein, osteocalcin, Runx2, and dentin sialophosphoprotein was analyzed. Gene expression studies by real-time polymerase chain-reaction revealed a concentration- and time-dependent decrease of mineralization markers. A subtoxic TEGDMA concentration (0.3 mM) reduced expression levels by 5 to 20% after 4 hrs and by 50% after 12 hrs. Furthermore, alkaline phosphatase activity and calcium deposition were significantly lower in dental pulp cells treated with TEGDMA over 14 days. These findings indicate that even low TEGDMA concentrations might inhibit mineralization induced by dental pulp cells, thus impairing reparative dentin formation after pulp capping with dentin bonding agents.
    Journal of dental research 02/2011; 90(2):257-62. · 3.46 Impact Factor
  • Article: Combination of 10% EDTA, Photosan, and a blue light hand-held photopolymerizer to inactivate leading oral bacteria in dentistry in vitro.
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    ABSTRACT: The goal of this study was to investigate the phototoxicity of Photosan in combination with EDTA and a hand-held photopolymerizer used in dentistry for light-curing resins against leading key pathogens in caries, endodontic treatment failures, and periodontitis respectively. Cellular uptake of Photosan was detected by fluorescence spectroscopy for Streptococcus mutans and Enterococcus faecalis but not for Aggregatibacter actinomycetemcomitans. Addition of 10% EDTA enabled the uptake of Photosan by A. actinomycetemcomitans. Killing of S. mutans and E. faecalis mediated by Photosan and blue light was concentration and light dose dependent, achieving a >or=99.9% (>or=3 log(10) reduction) efficacy of bacteria killing. In the presence of 10% EDTA, Photosan induced a reduction of >or=4 log(10) in the viability of A. actinomycetemcomitans at a concentration of 50 microg ml(-1), upon activation at a dose of 9.65 J cm(-2) for 60 s. EDTA alone, light alone, and Photosan alone were not able to kill bacteria. Ten per cent EDTA and Photosan cause a potent phototoxicity against oral bacteria upon illumination with a photopolymerizer. Increasing antibiotic resistance and insufficient drug concentrations within the sulcus fluid are responsible for lacking antimicrobial efficacy. This study provides useful information that combination of Photosan, EDTA, and a photopolymerizer may be a potentially powerful tool for the efficient destroying of key oral bacteria.
    Journal of Applied Microbiology 06/2009; 107(5):1569-78. · 2.34 Impact Factor
  • Article: Cytotoxicity and genotoxicity of pulp capping materials in two cell lines.
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    ABSTRACT: The aim of this study was to evaluate the cytotoxicity and genotoxicity of the new castor oil bean cement (COB) material in comparison to commonly used pulp capping materials. Specimens of COB, calcium hydroxide (Hydro C), and mineral trioxide aggregate (white and gray MTA) were extracted in culture medium (91.6 mm(2) sample surface mL(-1)). Transfected human pulp cells (tHPCs) were exposed to dilutions of the extracts for 1 h, and the generation of reactive oxygen species (ROS) was determined by flow cytometry (FACS) using H(2)DCF-DA as a dye. Survival of tHPCs was measured photometrically using a crystal violet assay after a 24-h exposure period. Genotoxicity as indicated by the formation of micronuclei in V79 cells, and the modification of the normal cell cycle by extracts of the materials was analysed by FACS. Clear cytotoxic effects were detected only with extracts of Hydro C under the current experimental conditions. The two MTA preparations induced an insignificant reduction in the number of cells. In contrast, the extracts of COB slightly induced cell proliferation. Extracts of Hydro C caused a twofold increase in ROS production, whilst the other tested materials were ineffective. An increase in the number of micronuclei was not detected with any material tested; Hydro C slightly increased the number of cells in G1 and G2. The COB and the two MTA preparations did not negatively influence cell survival or ROS production and may thus be further considered for pulp capping studies.
    International Endodontic Journal 04/2009; 42(3):227-37. · 2.18 Impact Factor
  • Article: Adhesion of eukaryotic cells and Staphylococcus aureus to silicon model surfaces.
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    ABSTRACT: Silicon wafers modified by silanisation with different functional groups are used to study the bioactivity of surfaces with varying physicochemical properties. Oxidation of the wafers created very hydrophilic surfaces, and moderately wettable surfaces were produced by coating with poly(ethylene glycol) (PEG). Immobilization of hydrocarbon chains to the wafers produced hydrophobic surfaces, and hydrophobicity was further increased by fluorocarbon coatings. The oxidized and the hydrocarbon-modified surfaces supported the adhesion of human MG-63 osteoblasts and 3T3 mouse fibroblasts as well as Staphylococcus aureus 8325-4. Adhesion of osteoblasts and fibroblasts, however, was decreased on highly hydrophobic fluorocarbon surfaces, whereas adhesion of S. aureus was supported. Coating of the fluorocarbon surface with fibronectin increased the number of attached eukaryotic cells, but the accumulation of bacteria remained unchanged. In contrast, surface coatings with PEG-groups inhibited the binding of S. aureus; however, the adhesion of the eukaryotic cells was high. The number of S. aureus on PEG-modified surfaces covered with fibronectin increased about twofold, yet it was still decreased to 25-30% related to the number of bacteria on other surfaces. These findings provide evidence that the PEG-modified surfaces showed selective bioactivity, preventing the attachment of a microbial pathogen but supporting the adhesion of eukaryotic cells.
    Journal of Biomedical Materials Research Part A 04/2008; 84(3):817-27. · 2.63 Impact Factor
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    Article: The induction of oxidative stress, cytotoxicity, and genotoxicity by dental adhesives.
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    ABSTRACT: Polymerized dental resin materials release residual monomers that may interact with pulp tissues. We hypothesized that dental adhesives might cause cytotoxicity in pulp cells via the generation of reactive oxygen species (ROS), which may also contribute to genotoxic effects in vitro. For cytotoxicity testing, transformed human pulp-derived cells were exposed to extracts of primers and bonding agents of Clearfil SE bond, Clearfil Protect bond, AdheSE, Prompt L-Pop, and Excite for 24h. The cytotoxicity of the same materials was also analyzed in a dentin barrier test device using three-dimensional pulp cell cultures. The generation of ROS in monolayer cultures was measured after a 1h exposure period by flow cytometry (FACS), and genotoxicity as indicated by the formation of micronuclei was determined in V79 cells after a 24h exposure period. The dentin primers and bonding agents decrease cell survival in a dose-related manner. Cytotoxicity of bonding agents based on concentrations which caused 50% cell death (EC50) were ranked as follows: Excite (0.16 mg/ml)>AdheSE bond (0.30 mg/ml)>Clearfil Protect bond (0.35 mg/ml)>Clearfil SE bond (0.37 mg/ml), and Prompt L-Pop bond (0.68 mg/ml). Dentin primers were about 10-fold less effective. In contrast, no cytotoxic effects of the dental adhesives were observed in a dentin barrier test device. Yet, all dental adhesives increased the amounts of ROS about fivefold in pulp cells in a dose-related manner, and, again, the bonding agents were more efficient than the dentin primers. Finally, the number of micronuclei was increased about sixfold by extracts of the AdheSE primer. Our results suggest that the cytotoxic potencies demonstrated by these materials might be of clinical relevance, since all dental adhesives disturbed the cellular redox state of pulp cells in monolayer cultures. As a result, the concentrations of biologically active ingredients of some of the agents may be high enough to modify pulp cell metabolism when the materials are used in deep cavities or directly contact pulp tissue.
    Dental Materials 03/2008; 24(3):362-71. · 3.13 Impact Factor
  • Article: Three-year clinical performance of cast gold vs ceramic partial crowns.
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    ABSTRACT: Cast gold partial crowns (CGPC) and partial ceramic crowns (PCC) are both accepted for restoring posterior teeth with extended lesions today. However, as esthetics in dentistry becomes increasingly important, CGPC are being progressively replaced by PCC. The aim of the present prospective split-mouth study was the comparison of the clinical performance of PCC and CGPC after 3 years of clinical service. Twenty-eight patients (11 men and 17 women) participated in the 3-year recall with a total of 56 restorations. In each patient, one CGPC (Degulor C) and one PCC (Vita Mark II ceramic/Cerec III) had been inserted at baseline. CGPC were placed using a zinc phosphate cement (Harvard); PCC were adhesively luted (Variolink II/Excite). All restorations were clinically assessed using modified US Public Health Service (USPHS) criteria at baseline, 1 year, 2 years, and 3 years after insertion. Twenty-eight CGPC and 14 PCC were placed in molars, and 14 PCC were placed in premolars. Early data were reported previously under the same study design. After 3 years, the evaluation according to USPHS criteria revealed no statistically significant differences between both types of restorations with the exception of marginal adaptation and marginal discoloration: A statistically significant difference within the PCC group (baseline/3 years) was determined for the criterion marginal adaptation. For the 3-year recall period, overall failure was 0% for CGPC and 6.9% for PCC. At 3 years, PCC meet American Dental Association Acceptance Guidelines criteria for tooth-colored restorative materials for posterior teeth.
    Clinical Oral Investigations 01/2008; 11(4):345-52. · 2.36 Impact Factor
  • Article: Effects of the dental monomer TEGDMA on the cytokine secretion in Murine RAW264.7 macrophages
    Naunyn-Schmiedebergs Archives of Pharmacology. 01/2008; 377:70-70.
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    Article: Inhibition of TEGDMA and HEMA-induced genotoxicity and cell cycle arrest by N-acetylcysteine.
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    ABSTRACT: Dental resin monomers like triethylene glycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) are able to cause an imbalance of the redox state in mammalian cells. The resulting oxidative stress originating from reactive oxygen species (ROS) has been associated with cytotoxicity. We hypothesized that ROS might contribute to the generation of genotoxicity by TEGDMA and HEMA as well. Therefore, we examined the formation of micronuclei in V79 cells by both resin monomers in the presence of the antioxidant N-acetylcysteine (NAC), which scavenges ROS. In addition, we analyzed the effects of TEGDMA and HEMA on the normal cell cycle in the presence of NAC. V79 fibroblasts were exposed to increasing concentrations of TEGDMA and HEMA in the presence and absence of NAC for 24h. Genotoxicity was indicated by the formation of micronuclei. The modification of the normal cell cycle was analyzed by flow cytometry (FACS). A dose-related increase in the number of micronuclei in V79 cells-induced by TEGDMA and HEMA indicated genotoxicity of both chemicals. However, the formation of micronuclei was reduced in the presence of 10 mmol/L NAC, indicating its protective role. A cell cycle delay in G2 phase caused by TEGDMA was absent when cells were co-treated with NAC. Similarly, the presence of NAC led to a reversion of the cell cycle delay in HEMA-treated cell cultures. Our results suggest that genotoxic effects and the modification of the cell cycle caused by TEGDMA and HEMA are mediated, at least in part, by oxidative stress.
    Dental Materials 07/2007; 23(6):688-95. · 3.13 Impact Factor
  • Article: Periodontal healing after non-surgical therapy with a new ultrasonic device: a randomized controlled clinical trial.
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    ABSTRACT: The aim of this study was to compare the clinical and microbiological healing outcomes following non-surgical periodontal therapy using the new Vector ultrasonic system versus scaling and root planing (S/RP) with Gracey curettes. The study comprised 20 chronic periodontitis patients. Using a split-mouth design, both treatment modalities were randomly applied to one quadrant of the upper and the lower jaws each. Clinical and microbiological parameters were assessed at baseline, 4 weeks, and 6 months after treatment. Furthermore, post-operative hypersensitivity was assessed. The Wilcoxon signed rank test (alpha=0.05) was used for statistical analysis. Both therapies provided statistically significant clinical and microbiological improvements of periodontal conditions after 4 weeks and 6 months. Hypersensitive teeth were found only 4 weeks after S/RP. Besides a significantly better bleeding on probing reduction in deep S/RP sites, no other clinical and microbiological parameters revealed significant differences between the sites treated with the Vector system or S/RP. Both the Vector system and S/RP provided favourable periodontal healing results, although in deep pockets S/RP appeared to achieve a better resolution of inflammation.
    Journal Of Clinical Periodontology 03/2007; 34(2):137-47. · 3.00 Impact Factor
  • Article: Effect of the dental resin monomer TEGDMA on the surface antigen expression of murine RAW264.7 macrophages
    Naunyn-Schmiedebergs Archives of Pharmacology. 01/2007; 375:75-75.
  • Article: Influence of autologous platelet concentrate on healing in intra-bony defects following guided tissue regeneration therapy: a randomized prospective clinical split-mouth study.
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    ABSTRACT: To investigate the influence of autologous platelet concentrate (APC) on early wound healing and regeneration outcomes following guided tissue regeneration (GTR) therapy. In 25 patients, two contralateral deep intra-bony defects were treated with beta-TCP and a bioresorbable GTR membrane. They were randomly assigned to test and control procedure. In test defects, APC was additionally applied. After 3, 6, and 12 months, healing results were assessed by clinical parameters and quantitative digital subtraction radiography. Post-operative membrane exposures occurred in 48% of the test sites and 80% of the control sites. Both groups revealed a significant clinical attachment level (CAL) gain of 5 mm after 12 months. Eighty-eight per cent of test and control sites showed a CAL gain of > or =4 mm. No clinical parameter revealed significant differences between test and control sites. A significant bone density gain was found in both groups after 3, 6, and 12 months. Only after 6 months, the bone density gain was significantly greater in the test defects. Within the limits of this study, autologous platelet concentrate did not seem to have a noticeable influence on the clinical and most of the radiographic outcomes following GTR. However, APC might reduce the occurrence of post-operative membrane exposures and accelerate bone density gain.
    Journal Of Clinical Periodontology 12/2006; 33(12):908-21. · 3.00 Impact Factor
  • Article: Growth factors and cytokines in autologous platelet concentrate and their correlation to periodontal regeneration outcomes.
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    ABSTRACT: To determine the concentration of naturally available biologic mediators in autologous platelet concentrates and their correlation with periodontal regeneration outcomes. In 25 patients with two intra-bony defects each, an autologous platelet concentrate (APC) was prepared by a laboratory thrombocyte apheresis technique pre-operatively. Both defects were treated using a bioresorbable guided tissue regeneration-membrane in combination with tricalciumphosphate (TCP). In the test defect, APC was additionally applied. In the APC, platelets were counted and the levels of growth factors and cytokines were determined by ELISA. Correlations between the platelet counts or the growth factor/cytokine levels and the potential clinical and radiographic regeneration outcomes due to APC were calculated after 3, 6, and 12 months. The APC contained 2.2 x 10(6) platelets/mul, which was 7.9 times more than in the venous blood. Transforming growth factor-beta1 (TGF-beta1), insulin-like growth factor-I (IGF-I), platelet-derived growth factor-AB (PDGF-AB), PDGF-BB, vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) were found in the APC, whereas interleukin-1beta (IL-1beta), IL-6, tumor necrosis factor alpha (TNFalpha), IL-4, and IL-10 were not detectable. The regression analysis showed a weak correlation between the platelet counts or the growth factor levels and the clinical and radiographic regeneration outcomes (r2<or=0.4). Autologous platelet concentrate contains relatively high concentrations of PDGF-AB, PDGF-BB, TGF-beta1, and IGF-I, but their potential influence on periodontal regeneration remains unclear.
    Journal Of Clinical Periodontology 11/2006; 33(11):837-45. · 3.00 Impact Factor
  • Article: Periodontal healing after non-surgical therapy with a modified sonic scaler: a controlled clinical trial.
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    ABSTRACT: The aim of this study was to compare the clinical and microbiological healing outcomes following non-surgical periodontal therapy using a modified sonic scaler system versus scaling and root planing (S/RP) with hand instruments. The study comprised 20 chronic periodontitis patients. Using a split-mouth design, both treatment modalities were randomly applied to one quadrant of the upper and lower jaws. Clinical and microbiological parameters were assessed at baseline, 4 weeks, and 6 months after treatment. Furthermore, post-operative hypersensitivity was investigated. The Wilcoxon signed-rank test (alpha = 0.05) was used for statistical analysis. With both therapy methods, periodontal conditions showed statistically significant clinical and microbiological improvements after 4 weeks and 6 months. Hypersensitive teeth were found only 4 weeks after S/RP. Besides a significantly better bleeding on probing reduction in deep S/RP sites and less time required for root instrumentation by the sonic scaler, no other clinical and microbiological parameters revealed significant differences between sites treated with the sonic scaler or S/RP. The sonic scaler system and S/RP seem to provide similarly favourable periodontal healing results, although in deep pockets S/RP appeared to achieve a better resolution of inflammation.
    Journal Of Clinical Periodontology 11/2006; 33(10):749-58. · 3.00 Impact Factor
  • Article: Partial ceramic crowns. Influence of preparation design and luting material on margin integrity--a scanning electron microscopic study.
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    ABSTRACT: This in vitro study examines the effects of three preparation designs and different luting agents on the marginal integrity of partial ceramic crowns. One hundred forty-four extracted human molars were prepared according to the following preparation designs: A. Coverage of functional cusps, B. Horizontal reduction of functional cusps and C. Complete reduction of functional cusps. Partial ceramic crowns (Vita Mark II, Cerec 3 System) were bonded to the cavities with: Variolink II/Excite (Vivadent), Panavia F/ED primer (Kuraray), Dyract/Prime and Bond NT (Detrey/Dentsply), and Fuji Plus/GC cavity conditioner (GC). The specimens were exposed to thermocycling and mechanical loading. Marginal adaptation was assessed on replicas using quantitative margin analysis in the scanning electron microscope (SEM). Significant differences were observed between the preparation designs in general. Coverage of functional cusps with preparation of butt joints and use of Variolink as luting material showed a tendency toward the lowest values for compromised adhesion, especially within the dentin. Significant differences could be determined between luting systems: resin-modified glass ionomer cement (RMGIC) caused fracture of the restorations and revealed higher values than all other luting materials for compromised adhesion at ceramic-luting agent and tooth-luting agent interfaces. The dentin-luting material interface, in general, showed higher percentages of compromised adhesion (38-100%) than enamel- and ceramic-luting material interfaces (0-30%). In conclusion, the SEM data indicate that, with adhesively bonded partial ceramic crowns, retentive preparation is not contraindicated and the choice of luting material is more relevant than the preparation design. Margins below the cemento-enamel junction reveal significant loss of adhesion in spite of adhesive luting techniques. The RMGIC cannot be recommended as a luting material for feldspathic partial ceramic crowns.
    Clinical Oral Investigations 04/2005; 9(1):8-17. · 2.36 Impact Factor
  • Article: Proteins in whole saliva during the first year of infancy.
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    ABSTRACT: During the first year of an infant's life, the oral environment is subject to drastic changes that coincide with the eruption of teeth. Proteins in saliva are important for protecting oral surfaces and provide receptors for bacterial adhesins. The objective of this longitudinal study was to monitor the general composition and expression of proteins in whole saliva of infants, to prove the hypothesis that expression of certain proteins changes during infant development, and might be associated with tooth eruption. The results showed a remarkable constancy in the overall pattern of salivary proteins and glycoproteins during infancy. Exceptions were the mucins and albumin. The mucins are expressed differentially, with first MUC7 and later MUC5B being predominant. Albumin, a marker of serum leakage, started to rise in whole saliva preceding tooth eruption. Thus, the expression of only few proteins appears to be changed during infant development.
    Journal of Dental Research 02/2005; 84(1):29-34. · 3.49 Impact Factor
  • Article: Metal content of saliva of patients with and without metal restorations.
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    ABSTRACT: Many in vitro studies have confirmed the corrosion of dental alloys. However, in vivo corrosion studies, for example, recording of the release of metal ions into saliva, are scarce, and data on the repeatability of the metal content measurements of saliva are lacking. The present study examined the metal content of saliva of patients with and without metal restorations and assessed the repeatability of these data. The composition of each patient's oral cast alloys was analyzed using the energy-dispersive X-ray analysis of metal biopsy specimens and was compared to the metals found in saliva. Saliva analysis was performed using atomic absorption spectroscopy. Chemical analysis comprised the metals Ag, Au, Co, Cr, Cu, Fe, Ga, In, Ni, Pd, Pt, Sn, and Zn. The metals Ag, Cr, Cu, Fe, Ni, and Zn were found in saliva of patients without metal restorations, but these data showed statistically significant differences in the metal content between consecutively performed samples per patient. The metals Ag, Au, Cr, Cu, Fe, Ni, and Zn were identified in saliva of patients with metal restorations being higher in concentration than in control patients. In 77% of the cases at least one metal of the restoration was found in the patient's saliva. However, the metal content showed statistically significant differences between replicate samples of the same patient taken at different times. The metal content of saliva is affected among other things by intraoral metal restorations, but present data do not support the idea that it is a reliable indicator for the systemic exposure to metals released from dental alloys.
    Clinical Oral Investigations 01/2005; 8(4):238-42. · 2.36 Impact Factor
  • Article: Effect of dentin on the antibacterial activity of dentin bonding agents.
    G Schmalz, Z Ergücü, K-A Hiller
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    ABSTRACT: Dentin bonding agents with antibacterial effects may inhibit secondary caries formation and pulp inflammation by eliminating residual bacteria in and on dentin. Therefore, the antibacterial effects of Prime & Bond NT (PB), Prime & Bond NT without fluoride (PBNF), Gluma Comfort Bond (GL), ABF, Xeno CF II (XE), 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEG-DMA), and 0.2% chlorhexidine were tested against Streptococcus mutans, S. sobrinus, and Lactobacillus acidophilus using the agar-diffusion method with and without bovine-dentin disks (200 microm and 500 microm thickness) placed between the bacteria and the test substances. Without dentin, ABF Primer showed growth inhibition for all bacterial strains. XE inhibited S. mutans and S. sobrinus, and PB S. sobrinus. ABF Bonding inhibited L. acidophilus. PBNF, HEMA, and TEGDMA did not have any antibacterial effects. Dentin disks of 500 microm thickness reduced the inhibitory effect of chlorhexidine to 23% to 54% compared with direct application. ABF Primer (nonpolymerized) produced inhibition zones against all tester strains regardless of dentin disks interposed or not. XE (against S. mutans and S. sobrinus) and PB (against S. sobrinus) did not produce any inhibition zones on 200 microm thick dentin. After polymerization, the ABF system did not inhibit bacterial growth on 200 microm thick dentin disks. A dentin barrier reduces significantly the antibacterial activity of chlorhexidine and dentin bonding agents.
    Journal of Endodontics 06/2004; 30(5):352-8. · 2.88 Impact Factor
  • Article: Salivary proteins and cytokines in drug-induced gingival overgrowth.
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    ABSTRACT: Little is known about the involvement of saliva in gingival overgrowth (GO). It was hypothesized that, in this situation, the composition of saliva is altered. Thus, proteins, albumin, cytokines, and growth factors in whole and glandular saliva were investigated. Differences between glandular and gingival contributions to the composition of saliva were explored in patients medicated with cyclosporin who exhibited GO (responders), those without GO (non-responders), and non-medicated subjects (controls). In whole saliva, interleukin-1alpha (IL-1alpha), IL-6, IL-8, epidermal growth factor (EGF), nerve growth factor (NGF), and albumin were detected, but in glandular saliva only EGF and NGF were identified. Albumin and IL-6 differed significantly between responders and controls, although the overall profile of salivary proteins remained unchanged. Thus, inflammatory cytokines and albumin are confined to whole saliva and are associated with GO, whereas its content of EGF and NGF appears unaffected by cyclosporin.
    Journal of Dental Research 05/2004; 83(4):322-6. · 3.49 Impact Factor
  • Article: Long-term clinical performance and longevity of gold alloy vs ceramic partial crowns.
    J Wagner, K-A Hiller, G Schmalz
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    ABSTRACT: Cast gold partial crowns (CGPC) are an accepted means of restoring posterior teeth. For aesthetic reasons, gold alloys are being increasingly substituted with ceramics. The aim of the present study was to investigate retrospectively the long-term clinical performance and survival of CGPC and compare the results to the ones already reported for ceramic partial crowns (CPC). The CGPC group consisted of 42 patients (24 male, 18 female) randomly sampled from a total of 106 patients with CGPC, with one restoration per patient. The CPC group consisted of 22 patients with a total of 42 restorations. Both types of restoration were done by one experienced dentist. Another two experienced dentists who were not involved in performing the restorations rated both kinds of partial crowns using the modified United State Public Health Service (USPHS) criteria [14]. The Median age of the CGPC was 57 months (range 3-157) and of the CPC and 63 months (range 24-72). Forty-one (98%) of the CGPC and 27 (64%) of the CPC were placed in molars, the rest in premolars. In each group, 40 (95%) restorations were still functioning without any necessity of replacement. Two teeth with CGPC, in situ for 4.5 and 11 years, respectively, had been extracted for periodontal reasons. Two CPC fractured and had to be replaced after 2 and 6.5 years in situ. The USPHS criteria results were similarly good for the gold and ceramic groups. Kaplan-Meier analysis revealed survival probabilities of 72+/-21% and 96+/-4% after 13 and 7 years, respectively, for the CGPC. Survival of the CPC was 81+/-15% after 7 years. No statistically significant difference among survival functions of CGPC and CPC was found. From this data, it can be concluded that the longevity of CPC is not inferior to that of gold alloys. However, more long-term studies comparing the clinical performance and longevity of these two types of indirect restoration in the posterior region with larger numbers of restorations are desirable.
    Clinical Oral Investigations 07/2003; 7(2):80-5. · 2.36 Impact Factor

Institutions

  • 1995–2012
    • Universität Regensburg
      • Lehrstuhl für Zahnerhaltung und Parodontologie
      Regensburg, Bavaria, Germany
  • 2009
    • Universidade Estadual Paulista
      • Departamento de Patologia
      São Paulo, Estado de Sao Paulo, Brazil
  • 2005–2009
    • Universitätsklinikum Regensburg
      Regensburg, Bavaria, Germany
  • 2008
    • Istanbul University
      • Faculty of Dentistry
      İstanbul, Istanbul, Turkey