Effect of Cements at Different Temperatures on the Clinical Performance and Marginal Adaptation of Inlay-Onlay Restorations In Vivo.

PURPOSE: To evaluate the clinical performance of inlays and onlays luted with two different resin cements, mixed at different temperatures and to evaluate the marginal adaptation of the restorations. MATERIALS AND METHODS: One hundred IPS e.max restorations (82 onlays, 18 inlays; 84 molars, 16 premolars) were placed in 50 patients (28 females, 22 males, mean age, 33 years). The restorations were assigned to six groups according to the luting agent temperature (25°C, 37°C, and 54°C) and cement type (Variolink N high viscosity or G-Cem Automix). All restorations were evaluated after 1 week and 1 year by two examiners using modified USPHS criteria. Replicas of 30 selected onlay restorations (5 per group) were assessed for marginal quality under a scanning electron microscope (SEM) at 200×. Marginal adaptation was quantitatively evaluated in terms of percentage of gap formation, and marginal gap width was measured. RESULTS: After 1 year, the total survival rates of the Variolink N high viscosity group and G-Cem Automix group were 100% and 93.8%, respectively. Three debondings occurred with the G-Cem Automix group, one from each temperature group. For 1-year clinical service time, no significant difference was noticed in the marginal adaptation of Variolink N high viscosity groups and the 37°C G-Cem Automix group, while 25°C and 54°C G-Cem Automix groups' marginal adaptation scores decreased (p < 0.05). Regarding the SEM evaluations, Variolink N high viscosity cement groups showed better marginal adaptation than G-Cem Automix cement groups (p < 0.05). Cementation with the cements preheated to 37°C increased continuous margins in both enamel-cement and cement-ceramic interfaces, but these results were not statistically significant (p > 0.05). Cements at different temperatures did not have significant effects on marginal gap widths of the restorations. CONCLUSIONS: The restorations cemented with Variolink N high viscosity cement mixed at the three tested temperatures exhibited better treatment options than the self-adhesive groups. Preheating the self-adhesive cement (G-Cem Automix) to 37°C can be an effective method to have better marginal adaptation than the other self-adhesive groups (25°C, 54°C) tested in this study.

In Vitro Comparison of Marginal and Internal Fit of Press-on-Metal Ceramic (PoM) Restorations with Zirconium-Supported and Conventional Metal Ceramic Fixed Partial Dentures Before and After Veneering.

PURPOSE: To compare marginal and internal fit between 3- and 4-unit press-on-metal (PoM) ceramic, zirconia-supported, and conventional metal ceramic fixed partial dentures (FPDs) before and after veneering. MATERIALS AND METHODS: Ten pieces for each 3- and 4-unit MC, IPS InLine PoM, and IPS e.max ZirCAD/Zir Press FPDs were produced. Cross-sections from silicone replicas were examined and measured with a light microscope. Occlusal, axial, intermarginal, and marginal mean adaptation scores of cross-sectioned replicas and means of measurements obtained from 4 sites were calculated independently. RESULTS: Mean values for molars were 78.44 ± 32.01 µm (MC), 89.84 ± 29.20 µm (PoM), and 85.17 ± 28.49 µm (Zir). Premolar values were 76.08 ± 27.92 µm (MC), 89.94 ± 23.49 µm (PoM), and 87.18 ± 28.25 µm (Zir). No difference existed between the means of 3- and 4-unit FPDs except the molar-intermarginal region. The mean value of 4-unit FPDs (93.88 ± 25.41 µm) was less than the 3-unit FPDs (103.68 ± 24.55 µm) at the molar-inter marginal region. A gap increase was observed in all sites except the molar-axio-occlusal region after veneering. According to the mean difference, gap increases at the molar-marginal, molar-intermarginal, and premolar-intermarginal regions were statistically significant. A statistical difference was found at the molar-marginal region for 4-unit MCR (p = 0.041) and 4-unit PoM FPDs (p = 0.042) before and after veneering. Gap increase after veneering of 4-unit metal ceramics at molar-intermarginal, premolar-marginal, and premolar-intermarginal regions (p = 0.020; p = 0.015; p = 0.004) was significant. CONCLUSION: The gap measurements of the IPS InLine PoM and IPS e.max ZirCAD/Zir Press groups were all clinically acceptable. No studies on marginal and internal fit in the IPS InLine PoM system have been published to date. This study should be supported with future studies. No significant increase was observed after press-veneering the IPS e.max ZirCAD frameworks with an IPS e.max ZirPress material; therefore, we recommend the use of this combination.

Minimally invasive veneers: current state of the art.

Ceramic veneers are considered a conservative solution for patients requiring improvement of the shape, color, or position of their anterior teeth. Ceramic veneers have been extensively and successfully used to mask intrinsic staining, to give the appearance of straightening, and to correct minor malformations of anterior teeth without the removal of substantial amounts of sound tooth substance. The current literature was reviewed to search for the most important parameters determining the long-term success and correct application of ceramic veneers.

Clinical and radiographic evaluation of early loaded maxillary anterior single-tooth bone-level implants.

PURPOSE: The aim of this study was to evaluate the clinical and radiographic outcomes of early loaded platform-switched implants in the anterior maxilla. MATERIALS AND METHODS: In this study, patients were treated with implants that supported all-ceramic single-tooth crowns and were followed for 2 to 4 years. Implants were evaluated on the basis of clinical and radiographic parameters, including Plaque Index, Sulcus Bleeding Index, peri-implant probing depths (PDs), Papilla Index, soft tissue recession, and marginal bone levels. Statistical analyses were performed. RESULTS: Fifty-five implants were placed in 47 patients. At the recall examinations, all implants had successfully integrated, demonstrating healthy peri-implant soft tissues as documented by standard clinical parameters. At the time of recall, 7 implants had been followed for 4 years, 30 implants for 3 years, and 18 implants for 2 years. Plaque accumulation scores of 2 and 3 were not noted at any point during the study. At baseline, the mean PD was 2.1 ± 0.6 mm, at 2 years it was 2.2 ± 0.6 mm, at 3 years it was 2.2 ± 0.6 mm, and at 4 years (7 implants), the mean PD was 1.9 ± 0.4 mm. There were no statistically significant differences between time intervals. Complete papilla fill was seen for 49 implants. All implants showed less than 0.5 mm of marginal bone loss; mean bone loss at the time of final recall was 0.12 ± 0.22 mm. Seven implants showed an increase in the level of bone contact. There were no statistically significant differences over time. CONCLUSION: Bone-level implants with a platform-switched design are a successful treatment modality for anterior single-tooth implants.

Esthetic outcome evaluation of maxillary anterior single-tooth bone-level implants with metal or ceramic abutments and ceramic crowns.

PURPOSE: The aim of this study was to evaluate the treatment outcome of implants placed in the maxillary anterior segment. MATERIALS AND METHODS: Patients were treated with bone-level implants (Straumann Bone Level Implant, Institut Straumann) that supported all-ceramic single crowns and were followed for 2 to 4 years. Titanium or ceramic abutments were used according to the quality of the soft tissue at each site. Esthetic parameters were recorded to assess treatment outcomes. Pink esthetic scores (PES) and white esthetic scores (WES) were used to evaluate the esthetic outcome of anterior single-tooth implant-supported crowns. Patient satisfaction was also evaluated by means of a questionnaire. RESULTS: Fifty-five implants were placed in 47 patients. At the recall examinations, all implants were confirmed to have successfully integrated and demonstrated healthy peri-implant soft tissues, as documented by generally accepted clinical parameters. Overall, the esthetic results were considered favorable, and there were no significant differences between restorations with ceramic or titanium abutments. WES values were slightly superior to PES values. None of the implants had mucosal recession. CONCLUSION: Objective and subjective evaluation of maxillary bone-level implants in the esthetic zone yielded satisfactory results. Pleasing esthetic outcomes and stable facial soft tissues were achieved.

Candida albicans adhesion on reinforced polymethylmethacrylate denture resin: effect of fibre architecture and exposure to saliva.

BACKGROUND AND OBJECTIVES: Fiber-reinforced composites (FRC) are used to reinforce the prosthetic and restorative appliances. This may result in the exposure of the FRCs which may affect the adherence of microorganisms. This study evaluated the adhesion of Candida albicans to a denture base resin (N = 48), reinforced with E-glass FRCs with different architectures [unidirectional (n = 16) and woven (n = 16)], when exposed to either saliva or distilled water. MATERIALS AND METHODS: Specimens without FRC reinforcement served as control (n = 16). After fiber surfaces were exposed, half of the specimens (n = 8/per group) were treated with saliva, the other half was stored in distilled water prior to C. albicans adhesion. The adhered microorganisms were counted under an optical microscope and the data were analyzed. RESULTS: When exposed to distilled water or saliva, specimens with unidirectional (5403.4 cells/cm(2) and 5013.4 cells/cm(2) , respectively) (p = 0.202), woven fibers (4053.5 cells/cm(2) and 3726.6 cells/cm(2) , respectively) (p = 0.283) and specimens without fibers (2250 cells/cm(2) and 2006.8 cells/cm(2) , respectively) (p = 0.423) showed C. albicans adhesion, being not significant. In general, all the specimens exposed to saliva showed 3582.2 cells/cm(2) C. albicans adhesion, while specimens exposed to distilled water showed 3902 cells/cm(2) C. albicans adhesion, yet being not significant (p = 0.436). Regarding fiber type, C. albicans adhesion was significantly affected by the exposed FRC architecture with more favorable results for woven fibers (p < 0.001). CONCLUSION: Polymethylmethacrylate without FRCs collected less C. albicans. The presence of saliva seems to reduce the adhesion.

Evaluating the additional effects of arthrocentesis on the condylar pathways of temporomandibular joint in patients with internal derangement treated with stabilizing splint.

OBJECTIVES: The purpose of this investigation is to find out the differences in the condylar pathways of the temporomandibular joint (TMJ) in patients treated with stabilizing splint and arthrocentesis accompanied by stabilizing splint in 6 months period. STUDY DESIGN: Forty patients who were assigned a clinical diagnosis of internal derangement of the TMJ were included in this study. Full arch stabilizing splints were made for all patients. Patients were divided into two groups; group A (patients who underwent arthrocentesis), group B (patients who did not underwent arthrocentesis). Computerized axiography was performed for each group before therapy (T0), on the 3(rd) month (T1), after arthrocentesis (TA) (for group A) and on 6th month (T2). Curve parameters were recorded in three-dimension; X axis (posteroanterior), Y axis (mediolateral), Z axis (superoinferior). Also the distance from the starting point of the movement on sagittal plane (S) was calculated. RESULTS: There was a significant increase in the value of Z (p = 0.014) and S (p = 0.038) in mediotrusion movement in group A. Also, there was a significant increase in the value of Z (p = 0.007) in protrusion/retrusion movement, value of Z (p = 0.019) and S value (p = 0.002) in mediotrusion movement and value of Y in open/close movement in group B. CONCLUSIONS: No positive effects on condylar pathways of an additional arthrocentesis to splint therapy alone in patients with internal derangement were found in this study.

Retention behaviors of different attachment systems: precious versus nonprecious, precision versus semi-precision.

The aims of this study were to investigate the retention force changes of different attachment systems after 10,000 insertion-separation cycles and the difference in retention force between precious and non-precious materials of the same attachment system. Four types of attachments (Ball, Rod, M3 stud, and AP-Piccolino), produced using both precious and non-precious metal alloys, were tested (n=6). Data were analyzed using analysis of variance (ANOVA), Tukey's multiple comparison test, and t-test at a significance level of p≤0.05. Retention forces of all attachment types were significantly decreased after 10,000 insertion-separation cycles (p≤0.05). Rod and M3 attachment systems showed an initial increase in retention force, then an eventual decrease. At the end of the test, precious types of M3 and AP-Piccolino attachments had significantly higher retention force values than their non-precious ones (p≤0.05). Friction between non-precious attachment parts resulted in a higher retention loss than precious metal alloys.

Marginal and internal adaptation of different superstructure and abutment materials using two different implant systems for five-unit implant-supported fixed partial dentures: an in vitro study.

PURPOSE: To evaluate the marginal and internal adaptation of five-unit implant-supported fixed partial dentures with different superstructure and abutment materials with two different implant systems. MATERIALS AND METHODS: Two mandibular epoxy resin models (one for each implant system) were fabricated, and implants were inserted in the canine, first premolar, and first molar regions. Thirty impressions of each model were then made. The 30 models of each group were divided into three subgroups: group 1, titanium abutment with metal (nickel-chromium) framework; group 2, titanium abutment with zirconium framework; and group 3, zirconium abutment with zirconium framework. The replica technique was used to examine the marginal and internal gap values. For each restoration, 20 measurements were performed, and the data were evaluated statistically using analysis of variance and the least significant difference post hoc test. RESULTS: The highest values for internal adaptation were observed at the occlusal surface in all groups. There were statistically significant differences in marginal measurements between subgroups. The smallest gaps were found in group 1 (79.361 µm), and the largest gaps were found in group 3 (131.242 µm). CONCLUSIONS: In this study, marginal and internal gap measurements were 79 to 131 µm. The marginal discrepancy of the tested materials could be considered clinically acceptable.

Retrospective analysis of prosthetic complications of implant-supported fixed partial dentures after an observation period of 5 to 10 years.

PURPOSE: The purpose of this study was to evaluate the incidence of the most common technical problems with implant-supported fixed partial dentures (FPDs) and to assess the survival and success rates (event-free survival) after 5 to 10 years of function. MATERIALS AND METHODS: All of the implants evaluated in this study were from a single manufacturer (Institut Straumann). Follow-up examinations were scheduled 1 week after suprastructure placement, 6 months later, and annually thereafter. Prosthesis-based data on survival/failure rates and technical complications were analyzed. RESULTS: In 95 partially edentulous patients, 231 Straumann implants were placed and restored with 177 implant-supported prostheses (125 single crowns, 18 splinted crowns on two adjacent implants, and 34 three-unit FPDs). One hundred thirty one solid abutments and 100 synOcta abutments were inserted. The survival rate of prostheses supported by implants was 97.7%. The prosthetic success rate (event-free survival) was 96.05%. After an observation period of 5 years, the cumulative incidence of screw loosening was 0%. Fracture of the veneering porcelain occurred in 3.95% of all restorations. Fractures of the superstructure framework were not observed. The overall incidence of complications after 5 years was highest for splinted crowns, which showed the lowest success rate (94.4%), followed by three-unit FPDs (96%) and single crowns (98.4%). CONCLUSIONS: Single-unit restorations or short-span FPDs supported by both synOcta and solid abutments on Straumann implants showed low rates of technical complications, the most common being fracture of the veneering porcelain.

The effect of different restorative and abutment materials on marginal and internal adaptation of three-unit cantilever implant-supported fixed partial dentures: an in vitro study.

PURPOSE: Passive fit is generally assumed to be a significant prerequisite for long-term implant success. The aim of this study was to evaluate the precision fit of three-unit implant-supported fixed partial dentures with different restorative and abutment materials on two implant systems: the Straumann and Astra Tech. MATERIALS AND METHODS: Two mandibular epoxy resin models (one for each implant system) were fabricated, and two implants were inserted at the first and second molar region. Poly(vinyl siloxane) impression material was used to make the dental impression. For each implant system, fifteen models were fabricated, and each group was divided into three subgroups (group 1: titanium abutment with metal framework, group 2: titanium abutment with zirconium framework, group 3: zirconium abutment with zirconium framework). The replica technique was used to examine the marginal and internal gap values. For each restoration, 20 measurements were performed, totaling 1200 measurements for all groups. Data were evaluated statistically using ANOVA and LSD post hoc test (p < 0.05). RESULTS: The highest values at internal adaptation measurements were found at the occlusal surface for all groups. When the mean values of the marginal measurements were assessed, the lowest measurements were found in group 3 (51.416 µm), and the highest values were found in group 1 (79.394 µm). There were statistically significant differences between subgroups for marginal measurements (p < 0.05). CONCLUSIONS: As included in our study, marginal measurement values were found to be 46 to 87 µm. The marginal discrepancy of the tested materials could be considered clinically acceptable.

Fracture resistance of manually and CAD/CAM manufactured ceramic onlays.

PURPOSE: This in vitro study aimed to evaluate fracture resistance in lithium disilicate onlays fabricated with IPS e.max Press and IPS e.max CAD systems and luted with different adhesive cements. MATERIAL AND METHODS: Fifty maxillary first molars were prepared using a mesio-occluso-disto-lingual onlay cavity model. Ten onlays from each group were cemented using etch-and-rinse adhesives and high-viscosity composite resin cement, and 10 were cemented with self-adhesive, dual-curing universal resin cement. Fracture resistance was measured. RESULTS: Significant differences were observed between resin cements (p < 0.05) and between materials (p < 0.05), but the interaction of these variables did not produce a significant difference. The fracture resistance of pressable ceramics was significantly higher than that of CAD/CAM onlays (p < 0.05), and Syntac Variolink was significantly higher than that of Multilink Sprint (p < 0.05). CONCLUSION: All groups showed clinically acceptable fracture strength results. According to the study, both the onlay fabrication system and adhesive cements can be a viable treatment option.

Maxillary sinus floor augmentation using bovine bone grafts with simultaneous implant placement: a 5-year prospective follow-up study.

PURPOSE: The aim of this study was to evaluate the 5 year clinical results of maxillary sinus floor augmentation using bovine bone grafts with simultaneous implant placement. MATERIAL AND METHODS: A total of 28 patients were enrolled in the study, and a total of 84 implants were placed into the grafted sites. Unilateral or bilateral sinus augmentation was performed, and implants were inserted into the augmented sinuses. After osseointegration and insertion of the prosthesis, the implants were evaluated by clinical and radiographic parameters. RESULTS: The cumulative implant survival rate after 60 months of loading was 100%. Periimplant bone loss was at clinically acceptable levels (0.146 and 0.34 mm after 1 and 5 years, respectively). CONCLUSIONS: Bovine bone grafts used in 1-stage sinus augmentation yields sufficient quality and volume of bone for predictable simultaneous implant placement.

Five-year treatment outcomes with four types of implants in the posterior maxilla and mandible in partially edentulous patients: a retrospective study.

PURPOSE: The aim of this retrospective study was to evaluate the outcomes, after 5 years of functional loading, of four different types of implants supporting prostheses in the posterior maxilla and mandible. MATERIALS AND METHODS: Patients missing posterior teeth were treated with implants between 1998 and 2004. The implants were evaluated by clinical and radiographic parameters and Plaque Index, Sulcus Bleeding Index (BI), peri-implant probing depths (PD), and marginal bone loss (MBL) were recorded. Repeated-measures analysis of variance, Kruskal-Wallis, and Wilcoxon signed rank tests were used for statistical analysis. RESULTS: In all, 244 implants were placed in 83 patients: 86 Straumann implants, 35 Swiss Plus implants, 90 Camlog implants, and 33 Frialit implants. Patients received 93 single crowns and 71 fixed partial dentures (FPDs). Nine FPDs were cemented to both implants and natural teeth, and 62 FPDs were supported by implants only. At the 5-year recall, plaque accumulation was significantly higher than at baseline for all groups (P = .01). Mean PD was 1.8 mm in the maxilla and 1.6 mm in the mandible. The mean PD values were 1.77 ± 0.52 mm for Straumann, 1.87 ± 0.64 mm for Swiss Plus, 2.33 ± 0.58 mm for Camlog, and 2.29 ± 0.46 mm for Frialit. MBL was 0.19 ± 0.07 mm for Straumann, 0.27 ± 0.06 mm for Camlog, 0.26 ± 0.07 mm for Swiss Plus, and 0.24 ± 0.07 mm for Frialit. The mean MBL of Straumann implants was significantly lower than that seen in the other groups (P = .001). CONCLUSION: The four types of implants resulted in similar clinical success after 5 years.

Five-year treatment outcomes with three brands of implants supporting mandibular overdentures.

PURPOSE: The purpose of this study was to evaluate clinical outcomes, posttreatment care, and patient satisfaction with overdenture treatment in the severely resorbed mandible. MATERIALS AND METHODS: Two implants were inserted in the intraforaminal region of 36 edentulous patients. Seventy-two implants were placed: 24 ITI (Institut Straumann), 24 SwissPlus (Zimmer Dental), and 24 Astra (Astra Tech). Implants were not loaded until osseointegration was complete. Following osseointegration and insertion of the prosthesis, the implants were evaluated by clinical and radiographic parameters. Clinical parameters, including Plaque Index, Sulcus Bleeding Index, peri-implant probing depth (PD), and marginal bone loss (MBL), were recorded, and any biologic and mechanical complications at baseline and recall evaluations were noted. Patient satisfaction with mastication, phonetics, retention, oral hygiene, and esthetics was also evaluated by means of a questionnaire. The results were analyzed statistically. RESULTS: The cumulative implant survival rate after 5 years of loading was 100%. There were significant differences in mean PD values between the three implant groups at baseline and recall evaluations. Mean PD values for the Astra group were significantly higher than those for the ITI and SwissPlus groups. Although the mean MBL was within clinically acceptable levels for all groups, there were significant differences among the three groups for MBL scores between baseline and 5 years. The mean MBL for the ITI group was significantly lower than the MBL values seen for the Astra and SwissPlus groups. Over the 60-month evaluation period, the most common prosthetic complications were mandibular denture fracture and dislodgement of the female attachment. CONCLUSIONS: Mandibular implant overdenture treatment is a successful treatment modality for the severely resorbed mandible.

Adherence of Candida albicans to denture base acrylics and silicone-based resilient liner materials with different surface finishes.

This study evaluated the surface roughness and Candida albicans adherence on denture base acrylic resins and silicone-based resilient liners with different surface finishes. Four commercial denture base acrylic resins (three heat polymerized and one room temperature polymerized) and five silicone-based liner materials (two heat polymerized and three room temperature polymerized) (10 x 10 x 2 mm) were tested in this study. The materials were processed against glass or plaster or finished with a tungsten carbide bur. Surface roughness measurements were made using a profilometer with an optical scanner probe. All specimens were ultrasonically cleaned in water for 15 s, autoclave sterilized, and contaminated with C. albicans solution for adherence assay evaluation. The materials processed against the glass surface showed significantly lower surface roughness values (0.11 +/- 0.1-1.66 +/- 1.1 microm) than those of the materials processed against the dental plaster (2.61 +/- 0.2-6.12 +/- 2.8 microm) or roughening with a bur (1.48 +/- 0.2-7.05 +/- 1.2 microm; p < 0.05, one- or two-way analysis of variance). Also, the materials processed against the glass surface showed lower C. albicans adhesion (mean ranks 120.36) than those of the materials processed against the dental plaster (mean ranks 139.77) or roughening with a bur (mean ranks 143.06), but the differences were not statistically significant (p > 0.05, Kruskal-Wallis and Mann-Whitney). In all types of surface finishes, C. albicans adhesion on denture base acrylics was significantly less (mean ranks 90.18-90.40) than those of silicone liners (mean ranks 119.38-205.18; p < 0.01, Kruskal-Wallis).

Three-year treatment outcomes with three brands of implants placed in the posterior maxilla and mandible of partially edentulous patients.

STATEMENT OF PROBLEM: Survival rates of implants in posterior regions vary among clinical studies. Problems occur more often in the posterior segment of the maxilla due to proximity of the maxillary sinus and reduced quality or quantity of alveolar bone. PURPOSE: This clinical study evaluated the treatment outcomes of 3 brands of implants in the posterior maxillae and mandibles of 63 patients. Treatment outcomes of all implants were assessed according to implant type, location, patient gender, periodontal status, and prosthesis type. MATERIAL AND METHODS: A total of 203 implants-105 ITI (ITI), 53 Camlog (CAM), and 45 Frialit (FRI)-were placed in 63 patients (38 women, 25 men). One hundred twelve implants were located in the posterior mandible and 91 in the posterior maxilla. All implants were longer than 10 mm and had a diameter larger than 3.5 mm. Implants in the ITI group were placed in a 1-stage surgery. The CAM and FRI groups were treated with a 2-stage surgical protocol. Implants were not loaded until osseointegration was complete, which was determined clinically and radiographically. At that point, implants were restored with 50 single crowns and 81 fixed partial dentures (FPDs). While 11 FPDs connected implants to natural teeth, 70 FPDs were supported by implants only. Standardized radiographs were made, and clinical parameters were recorded at prosthesis insertion (baseline) and at each recall evaluation (6, 12, 24, and 36 months). Plaque index (PI), sulcus bleeding index (SBI), peri-implant probing depth (PD), and radiographic marginal bone loss (MBL) levels were recorded at baseline, along with any biological and mechanical complications. Repeated-measures ANOVA, Kruskal-Wallis test, Wilcoxon signed rank test, and paired samples tests were used for statistical analysis (alpha=.05). RESULTS: One implant was lost during the osseointegration period in 1 woman due to infection. The cumulative implant treatment outcome was 99.3%. At the 3-year recall, plaque accumulation was significantly higher than baseline scores (P=.01, Wilcoxon signed rank test). Eight percent of the patients presented>2 mm PD at 2-year recall. The influence of observation time was found to be significant for the mean MBL values between groups (P=.001). When MBL values were compared between groups, no significant differences were found. For 1 patient in the FRI group, abutment loosening was observed and both the crown and the abutment were replaced. Patient satisfaction in all groups was high. CONCLUSION: The 3 brands of implants evaluated in this study exhibited similar positive treatment outcomes after 3 years.

Evaluation of the methods used for impression making for different implant systems in prosthetic dentistry

A fabricação de prótese total ou fixa suportada por implantes requer precisa transferência das infra-estruturas e dos componentes dos implantes para um modelo de gesso. Com o aumento no número de sistemas de implante, as técnicas de impressão também aumentaram, o que depende de cada sistema. Esse artigo resiva e descreve os procedimentos e fatores que afetam a adequada moldagem em diversos sistemas de implante baseado em informações de artigos completos em inglês de revistas indexadas no Medline entre os anos de 1979 e 2005, livros-textos, and em informações obtidas a partir dos fabricantes dos sistemas de implantes comumente usados.

Effect of thermocycling on tensile bond strength of six silicone-based, resilient denture liners.

STATEMENT OF PROBLEM: Adhesion failure between silicone resilient denture lining materials and denture base resin is commonly encountered in clinical practice. Adhesion failure results in localized unhygienic conditions at the debonded regions and often causes functional failure of the prosthesis. PURPOSE: The purpose of this study was to investigate the effect of thermocycling on the tensile bond strength of 6 soft lining materials. MATERIAL AND METHODS: Six commonly used silicone-based resilient denture liners (Ufigel C, Ufigel P, Mollosil, Molloplast B, Permafix, and Permaflex) were chosen for the investigation. The bond strength was determined, in tension, after processing to PMMA. The resilient denture liners for each group (n = 24) were 10 x 10 x 3 mm and were processed between 2 polymethyl methacrylate specimens according to manufacturer's instructions. Two PMMA specimens were prepared by investing brass dies with a 3-mm-thick spacer in a denture flask. Specimens were made by processing the resilient denture liners against the polymerized PMMA block. After polymerization, the brass spacer was removed from the mold, the 2 PMMA resin specimens were trimmed, and the surfaces to be bonded were smoothed. The PMMA block was placed back into the molds and the resilient denture liners were packed into the space made by brass spacer, trial packed, and polymerized according to the manufacturer's instructions. Half of the specimens for each group were stored in water for 24 hours, and the other half were thermocycled (5000 cycles) between baths of 5 degrees and 55 degrees C. All specimens were placed under tension until failure in a universal testing machine at a crosshead speed of 5 mm/min. The maximum tensile stress before failure and mode of failure were recorded. The mode of failure was characterized as cohesive, adhesive, or mixed mode, depending on whether the fracture surface was in the soft liner only, at the denture base-soft liner interface only, or in both. Failure strength was recorded in kg/cm(2). Results were tested by multiple analysis of variance (ANOVA) for mode of failure (adhesive, cohesive, and mix), 2-way ANOVA (storage-products), and 1-way ANOVA (storage-products interaction, before and after thermocycling). Duncan's test was used to determine whether significant changes in the tensile bond properties of the materials occurred during thermocycling. RESULTS: Varying degrees of bond strengths were found for soft lining materials and were significantly different (P<.05). Results of this study also indicated that the bond strengths of soft lining materials had significantly decreased after thermocycling except Ufigel C and Mollosil. CONCLUSIONS: Because the adequate adhesive value for soft lining materials is given 4.5 kg/cm(2), all of the materials were acceptable for clinical use.

Oral hygiene habits, denture cleanliness, presence of yeasts and stomatitis in elderly people.

The purpose of this study was to determine oral hygiene habits, denture cleanliness, presence of yeasts and denture stomatitis in elderly people. Seventy complete denture wearers were investigated clinically and mycologically. Subjects were evaluated according to, presence of denture stomatitis, presence of yeasts, denture cleanliness, frequency of denture brushing and denture cleaning methods. Swabs were taken from the palate investigated mycologically in order to identify the yeast colonies. No statistical relationship was found between denture stomatitis and frequency of denture brushing and denture cleaning methods. However, there was a statistically significant relationship between denture stomatitis, yeasts' presence and denture cleanliness.