RESUMO
AIM: To evaluate the effect of two antioxidant formulations (sodium ascorbate and α-tocopherol) on fracture resistance of endodontically treated teeth. MATERIALS AND METHODS: Sixty human premolars were endodontically treated and divided into six groups (n = 10): G1 (negative control)-unbleached and restored with composite resin; G2 (positive control)-bleached in three sessions, using hydrogen peroxide (15 H2O2) plus titanium dioxide (TiO2) nanoparticles, photoactivated by LED laser system and restored with composite resin; G3-bleaching similar to G2, after the use of 10% sodium ascorbate gel for 24 hours and restored with composite resin; G4-similar to G3, but with the use of 10% sodium ascorbate solution and restored with composite resin; G5 and G6-similar to G3, but with the use of 10% α-tocopherol in alcohol or carbopol, respectively, and was also restored. A mechanical fracture resistance test was performed and the Kruskal-Wallis test was used to evaluate the results (α = 0.05). RESULTS: No statistical difference was observed in fracture resistance between groups (p > 0.05). Regarding the antioxidant and pharmaceutical formulation applied, no statistical difference was detected in any comparison (p > 0.05). The frequency of fractures considered favorable was higher in G1 and G3 compared to the other groups. CONCLUSION: The endodontically treated teeth bleached with 15 H2O2 plus TiO2 nanoparticles and photoactivated with the LED laser did not decrease the fracture resistance and the use of sodium ascorbate or α-tocopherol did not increase the crown fracture resistance. CLINICAL SIGNIFICANCE: The literature reports a significant reduction in the bond strength of restorations on the bleached dentin. Therefore, the use of antioxidant agents may have a promising effect on fracture resistance of endodontically treated teeth.
Assuntos
Clareamento Dental , alfa-Tocoferol , Antioxidantes , Ácido Ascórbico , Resinas Compostas , Humanos , Peróxido de HidrogênioRESUMO
This article reports an uncommon case of talon cusp on a geminated permanent maxillary central incisor, including details of the clinical and radiographic findings and treatment. A 28-year-old woman presented at the university dental clinic, and intraoral examination revealed a maxillary central incisor of abnormal size with a prominent accessory cusp on the lingual aspect. The case was diagnosed as talon cusp on a geminated tooth. Early diagnosis of this anomaly is important since it may cause clinical problems such as esthetic concerns, caries and tooth crowding. In the present case, these anomalies did not complicate the subsequent endodontic treatment.