Three-year clinical evaluation of different restorative resins in class I restorations.

The aim of the present study was to evaluate the three-year clinical performance of a nanofilled resin composite, a packable resin composite, and silorane-based resin restorations in Class I occlusal cavities. Twenty-eight patients with at least three similar-sized occlusal lesions in molar teeth participated in the study. A total of 84 Class I occlusal restorations were placed: 28 with nanofilled resin composite (Filtek Supreme), 28 with packable resin composite (P60), and 28 with silorane-based resin (Filtek Silorane). Filtek Supreme and P60 were used with their respective etch-and-rinse adhesive system, Adper Single Bond 2, and Filtek Silorane was used with its respective self-etch adhesive, Filtek Silorane Adhesive. All restorations were placed by the same operator. The restorations were evaluated at baseline, at six months, and annually for three years according to modified US Public Health Service criteria by two calibrated examiners who did not know which restorative resin had been used. The three restorative materials for each category were compared using the χ (2) test at a significance level of 0.05. Cochran's Q test was used to compare the changes across the five time points for each restorative material. McNemar's test followed by Bonferroni adjustment was used when significance differences were found. At the end of the three years, 60 restorations were evaluated in 20 patients, with a recall rate of 71.4%. The retention rate was 100% for all restorative resins. Eight restorations from the P60 group, ten from the Filtek Supreme group, and nine from the Filtek Silorane group were rated Bravo for marginal discoloration. For marginal adaptation, three P60, five Filtek Supreme, and 11 Filtek Silorane restorations were rated Bravo. No statistically significant differences in overall clinical performance were found between the restorative materials except for marginal adaptation. P60 showed the best marginal adaptation at the end of the three years. No differences were observed between the restorative resins for any of the evaluation criteria tested (p>0.05). None of the restorations showed postoperative sensitivity, secondary caries, or loss of anatomic form. All restorative resins performed equally well in clinical conditions during the three-year evaluation, and no significant differences were found among them, except for marginal adaptation, in which P60 showed superior results.

Clinical evaluation of different adhesives used in the restoration of non-carious cervical lesions: 24-month results.

BACKGROUND: The aim of this study was to compare after 24 months the clinical performance of cervical restorations placed with the use of an etch-and-rinse and an all-in-one adhesive. METHODS: Twenty-four patients with at least one pair of non-carious cervical lesions participated in this study. One hundred and twenty-three cervical lesions were restored (62 etch-and-rinse adhesive, Solobond M; 61 all-in-one adhesive, Futurabond NR). A nanohybrid resin composite, Grandio, was used as the restorative material. Restorations were evaluated according to modified USPHS criteria by two independent examiners. The survival rates of the restorations were calculated by the Kaplan-Meier estimator and log-rank test. The restorations in each category were compared using the Pearson chi-square test, while the performance of restorations at the baseline and at each recall time was evaluated by McNemar's test (p < 0.05). RESULTS: The recall rate of patients was 100%. The retention rates were 82% and 75% at 6 months and 77% and 62% at 12 months for Solobond M and Futurabond NR, respectively. At the 24-month recall, the retention rate was 69% for Solobond M and 49% for Futurabond NR, and this difference was statistically significant (p < 0.05). No statistically significant difference was found for colour match, marginal staining, or marginal adaptation between the adhesives (p > 0.05). None of the restorations had secondary caries, loss of anatomical form, or surface texture changes. CONCLUSIONS: Cervical restorations placed with an etch-and-rinse adhesive showed higher retention than an all-in-one adhesive.

Bond strength of different adhesive systems to dental hard tissues.

This study compared the shear bond strengths of different adhesive systems to enamel and dentin of different depths. The adhesive systems used were: Single Bond one-bottle total-etch; AQ Bond one-step self-etching, Clearfil SE Bond two-step self-etching and Tyrian SPE/One-step Plus two-step self-etching. Eighty extracted non-carious human mandibular molars were mounted in self-curing resin and the occlusal surfaces were ground with a mechanical grinder to obtain flat occlusal enamel surfaces. After applying the adhesive systems, a plastic tube was attached to the enamel surfaces. The tube was filled with a universal hybrid resin composite, which was then polymerized. The specimens were stored in water at 37 degrees C for 24 hours. Shear bond testing was carried out using an Instron Universal testing machine with a crosshead speed of 1 mm/minute. The occlusal enamel of the 80 teeth was removed to determine the bond strengths of the adhesives to superficial dentin. To obtain deep dentin, the same teeth were ground deep towards the pulp, with the remaining dentin thickness approximately 0.7 mm. The adhesives and restorative material were then applied to the prepared dentin surfaces following the methodology described above. For occlusal enamel surfaces, the bond strength of Single Bond was significantly higher than the other adhesives. Single Bond, Clearfil SE Bond and Tyrian SPE/One-step Plus performed equally when bonded to superficial dentin; the lowest bond strength was obtained with AQ Bond. On deep dentin, the highest bond strengths were obtained with Clearfil SE Bond. For each adhesive system, shear bond strength to enamel was statistically higher than it was to either superficial or deep dentin. There were no significant differences between shear bond strengths to superficial versus deep dentin, regardless of adhesive.

Bond strength of a self-etching adhesive system to caries-affected dentin.

This in vitro study evaluated the microtensile bond strengths of sound versus caries-affected dentin using a self-etching adhesive system, Clearfil SE Bond, with or without additional acid pre-conditioning. Extracted human mandibular molars with occlusal caries extending halfway through the dentin were used. In the first group, the teeth were bonded with the self-etching adhesive Clearfil SE Bond according to the manufacturer's instructions. In the second group, prepared dentin surfaces were etched with 37% phosphoric acid prior to applying the same self-etching adhesive. After the bonding procedure, all specimens were built up with composite resin and stored in water for 24 hours. The teeth were serially sectioned vertically into 0.7-mm slabs and trimmed into an hourglass shape for measuring microtensile bond strength. Each specimen was attached to a Bencor device and stressed in tension at a crosshead speed of 1 mm/minute. Statistical analysis was performed using two-way ANOVA and the Tukey HSD test (p<0.05). The microtensile bond strengths of Clearfil SE Bond to sound dentin (32.9) were significantly higher than to caries-affected dentin (15.9). In the second group where acid etching was performed prior to applying Clearfil SE Bond, there were no statistically significant differences between the microtensile bond strengths of sound (19.2) and caries-affected dentin (16.3). While bond strengths to sound dentin were decreased by using additional acid etching prior to applying Clearfil SE Bond, this procedure revealed no statistically significant differences in bond strengths for the caries-affected dentin.

In vitro analysis of the effects of acid or laser etching on microleakage around composite resin restorations.

OBJECTIVES: The aim of the present study was to determine the effect of two conditioning methods, phosphoric acid and XeCl laser application on microleakage at composite resin restorations. METHODS: Class II MOD (mesio-occluso-distal) cavities were prepared on 90 extracted human wisdom teeth with one proximogingival margin on enamel and the other on dentin. Phosphoric acid (37%) and a XeCl excimer laser system were used for the etching procedure. The prepared teeth were randomly assigned to six groups: In group 1, acid-etching of the enamel margins was followed by application of enamel bonding, in group 2 additionally a dentin bonding system was used. In group 3, acid-etching of the enamel and dentin (total etch) was followed by the application of dentin bonding. In group 4, laser-etching of enamel margins was followed by the application of enamel bonding, in group 5 dentin bonding was used additionally. In group 6, laser-etching of enamel and dentin margins was followed by the application of dentin bonding. All restorations were placed incrementally and polymerized with a halogen light source. After restoration, all samples were thermocycled and stained in 0.5% basic fuchsin and sectioned longitudinally in a mesio-distal plane. Microleakage was scored by means of a stereomicroscope. The margins of the restorations at tooth-resin interface were examined with a scanning electron microscope. RESULTS: In all groups, marginal leakage was more extensive at the gingival margin that was in dentin than at the gingival margin in enamel. Microleakage scores and the gap at the tooth-resin interface were significantly lower in all acid-etched groups than in laser-etched groups. CONCLUSION: Acid-etch technique is more effective than the investigated laser-etch technique at 308nm concerning the reduction of marginal leakage in composite restorations.

Endosseous vent-plant implants: 24-year case report.

In this article, a case of a vitallium endosseous vent-plant implant which was inserted 24 years ago is reported. The patient has been using the implant without any problem since then.

Effect of splinting on abutment tooth movement.

The effect of splinting on abutment tooth movement was investigated in an in vitro study. An acrylic resin mandibular model with missing molars and a removable partial denture framework were constructed. The roots of the premolars and edentulous ridges were coated with silicone rubber. A modified Ney surveyor was used for load application, and abutment tooth movement measurements were made with a macroperiodontometer. Four conditions were tested by applying unilateral loadings: 1. Single abutments of both sides 2. Load side double abutment 3. Nonload side double abutment 4. Double abutments of both sides The results showed that a significant decrease in the magnitude of movement resulted when the abutment teeth were splinted.