Resumo

FERREIRA, Ricardo; MILDEMBERG, Bárbara; GADOTTI, Bruna Cristina  e  GARCIA, Rubens Nazareno. Evaluation of the endodontic treatment influence on the bond strength of fiber posts reinforced by a restorative composite. RSBO (Online) [online]. 2011, vol.8, n.2, pp. 174-181. ISSN 1984-5685.

INTRODUCTION AND OBJECTIVE: Fiber posts are widely used to increase the mechanical strength of the restorations. The aim of this study was to evaluate the bond strength of fiber posts reinforced by a restorative composite to radicular dentin on its cervical, middle and apical thirds, regarding to post preparation prior or posterior to the endodontic treatment. MATERIALS AND METHODS: Thirty bovine incisors were used, which had their debris removed, washed in tap water, and stored frozen. The samples were divided into two groups (n = 15) - according to the treatment applied previously to the installation of the posts: Group 1 - root canal obturation followed by root canal preparation for fiber posts bonding; and Group 2 fiber posts preparation followed by root canal obturation. The posts were cemented and the roots were cut on their cervical (C), medium (M) and apical (A) thirds - for push out test application. Bond strength was calculated in MPa and data were statistically analyzed by Anova and Tukey test (p < 0.05). RESULTS: The mean values were (MPa ± SD): G1C - 4.0 ± 6.0; G1M - 3.5 ± 2.9; G1A 7.2 ± 6.3; G2C - 12.7 ± 8.1; G2M - 11.6 ± 10.2; G2A - 6.5 ± 8.1. The cervical and middle thirds of group 2 had the highest mean values, showing significant statistically difference compared to group 1. For apical third, no significant statistically differences were found among groups. When the cervical, middle and apical thirds were analysed separately, no significant statistically differences were found. CONCLUSION: The post preparation prior to root canal obturation increased the bond strength of fiber posts reinforced by a restorative composite.

Palavras-chave : nonvital tooth; post and core technique; shear bond strength.