Resistência de união de diferentes técnicas de inserção de resina composta em restaurações Classe I

Abstract

In the scientific literature, controversy persists regarding the impact of insertion techniques on the longevity and bond strength of composite resin restorations to the tooth structure. In this context, the present study aimed to evaluate the bond strength and failure patterns of different composite resin insertion techniques in extracted human teeth. Twenty-four sound molars were subdivided into 3 groups according to the restorative technique: horizontal incremental (RCH), oblique incremental (RCO) and bulkfill technique (RCB). All teeth underwent a standardized procedure and were restored according to the restorative technique allocated to each group. They were then subjected to a cutting machine (ODEME OCP 100 LC, Santa Catarina, Brazil) and microtensile test (ODEME OM100, Santa Catarina, Brazil), at a speed of 0.5mm/sec until failure. The evaluation of the results was carried out with the aid of a microscope, at a magnification of 30x, classifying the failures as adhesive, cohesive (in resin or dentin) or mixed. For the comparative analysis of tensions, descriptive analysis and a mixed linear regression model were used. Additionally, Weibull analysis was used to investigate the probability of fracture, adopting a statistical significance level of 0.05 and the statistical programs Matlab (R2021b) and IBM® SPSS® v28. Of the 158 specimens analyzed, there was no statistically significant difference between the groups (p=0.769), nor a significant association between the type of fracture and the techniques used (p>0.05). This study concluded that there is no difference in the bond strength of the different composite resin insertion techniques evaluated.