Clinical evaluation of two packable posterior composites: a five-year follow-up.

BACKGROUND: Research has suggested that packable resin-based composites inserted with a placement technique similar to amalgam condensation can reduce the sensitivity associated with posterior restorations. The authors evaluated the clinical performance, including associated sensitivity, of two packable composites in a randomized five-year clinical trial. METHODS: A single operator randomly placed two restorations in each of 33 patients: one restoration consisting of Alert (Jeneric/Pentron, Wallingford, Conn.) and the other consisting of SureFil (Dentsply/Caulk, Milford, Del.). There were 30 Class I and 36 Class II restorations. Two independent evaluators evaluated the restorations by using modified U.S. Public Health Service criteria. The authors analyzed data by means of the Fisher, chi(2) and McNemar tests at P < .05. RESULTS: Of 60 restorations evaluated at five years, two Class II restorations (one SureFil, one Alert) failed. All other restorations received the highest score possible for sensitivity and vitality. The only difference between the composites at the five-year recall was the significantly better surface texture of SureFil. The authors observed significantly different scores between the baseline and at five years for marginal discoloration (Alert and SureFil), surface texture (Alert and SureFil) and color (SureFil). CONCLUSIONS: Both packable resin-based composites showed excellent durability during the five-year follow-up. CLINICAL IMPLICATIONS: The investigated resin-based composites are suitable for posterior restorations.

Influence of occlusal access on demineralized dentin removal in the atraumatic restorative treatment (ART) approach.

PURPOSE: To verify the influence of cavity access diameter on demineralized dentin removal in the ART approach. METHODS: 40 non-carious human premolars were randomly divided into four groups. The occlusal surface was ground flat and the teeth were sectioned mesio-distally. The hemi-sections were reassembled and occlusal access preparations were carried out using ball-shaped diamonds. The resulting size of the occlusal opening was 1.0 mm, 1.4 mm, 1.6 mm and 1.8 mm for Groups A, B, C, and D, respectively. Standardized artificial carious lesions were created and demineralized dentin was excavated. After excavation, the cavities were analyzed using: (a) the tactile method, (b) caries-detection dye to stain demineralized dentin, as proposed by Smales & Fang, and (c) Demineralized Tissue Removal index, as proposed in this study. Statistical analysis was performed using Fisher, Spearman correlation coefficient, kappa, Kruskal-Wallis and Miller tests (P < 0.05). RESULTS: The three methods of evaluation showed no significant difference between Groups A vs. B, and C vs. D, while statistically significant differences were observed between Groups A vs. C, A vs. D, B vs. C and B vs. D. Based on the results of this study, the size of occlusal access significantly affected the efficacy of demineralized tissue removal.

Influence of ultrasonic setting on tensile bond strength of glass-ionomer cements to dentin.

PURPOSE: The aim of this study was to evaluate the influence of ultrasonic treatment on the bond strength of glass-ionomer cements to dentin. MATERIALS AND METHODS: Conventional (Fuji II: a; Ketac-Fil Plus: b), resin-modified (Fuji II LC Improved: c; Photac-Fil Quick Aplicap: d), and more viscous conventional (Ketac Molar: e) glass-ionomer cements were tested. Fifty human molars were sectioned mesiodistally, embedded in epoxy resin with exposed buccal or lingual surfaces, and ground to obtain a flat dentin surface. A matrix with a central orifice in the shape of an inverted truncated cone was built with a bovine tooth and positioned on the dentin surface. In the control groups, the materials were inserted into the matrix. In the test groups, the ultrasonic treatment was applied to the surface of the matrix and the surface of the glass-ionomer cements. The specimens were stored in deionized water for 24 h at 37 degrees C and subjected to bond strength tests. Data were analyzed using two-way ANOVA and Tukey's tests. RESULTS: The mean bond strengths in MPa for the control groups were: a: 2.21, b: 1.85, c: 8.65, d: 5.93, and e: 2.10. The results for the test groups were: a: 3.33, b: 2.19, c: 9.95, d: 6.10, and e: 2.65. Ultrasonic treatment statistically increased the tensile bond strength of all tested cements (p < 0.05). CONCLUSION: Ultrasonic treatment improved the bond strength of the glass-ionomer cements to dentin after 24 h.

The effect of dentin adhesive and cure mode on film thickness and microtensile bond strength to dentin in indirect restorations.

This study evaluated the influence of dentin adhesive application technique (pre-curing vs non precuring) on microtensile bond strength (microTBS) to dentin and adhesive layer thickness in indirect resin restorations. Seven proprietary dentin adhesives were tested, including one-step and multistep products. Experimental groups included adhesive pre-cure (PC) with a halogen light source and no pre-cure (NPC) prior to resin cement insertion. Thirty caries-free molars received an MO inlay preparation. Inlays made with Tetric Ceram resin composite were cemented using a dual-cured resin luting agent. Prior to inlay cementation, each tooth was treated with one dentin bonding agent, using pre-cure (PC) or no pre-cure (NPC). After storage in distilled water at 37 degrees C for 24 hours, the teeth were sectioned along their long axis to produce serial sticks for microtensile bond strength testing at 0.5 mm/minute. The results were subjected to statistical analysis by one-way and two-way analysis of variance (ANOVA) and Tukey's multiple comparison test (p < or = 0.05). For the film thickness evaluation, 10 additional teeth were restored and sectioned mesiodistally. The thickness of the adhesive layer was evaluated by SEM at 1000x magnification at the pre-selected locations. The microTBS varied from 11.7 +/- 4.5 MPa to 43.4 +/- 9.8 MPa. The effect of pre-curing the adhesive was material specific. No adhesive layer was visualized for the adhesives used without the pre-curing step. The thickness of the adhesive layer for the pre-cured groups varied according to the different areas analyzed.

Avaliaçäo de agentes de proteçäo superficial para cimento de ionômero de vidro / The evaluation of the surface protect agent for glass ionomer cement

O objetivo deste trabalho foi avaliar a efetividade de tratamentos superficiais para proteçäo de cimento ionomérico restaurador, através de quantificaçäo espectrofotométrica da penetraçäo de azul de metileno em corpos de prova. Vários agentes mostraram-se parcialmente efetivos na proteçäo do cimento de ionômero de vidro, mas os melhores resultados foram obtidos com esmaltes incolores de baixa viscosidade