Análise pelo método dos elementos finitos de restaurações de resina composta em lesões cervicais não cariosas

Abstract

The purpose of this work was to use the three-dimensional finite element method to evaluate the stress distribution in a maxillary second premolar with different cervical lesions restored with two types of composite. Six 3D tooth models were generated having U- or V-shaped lesions with three different depths: U1 and V1 (0.5mm), U2 and V2 (1.0mm), U3 and V3 (1.5mm). Composite restorations with low (RLE) and high Young’s modulus (RHE) were simulated, with 5GPa and 22GPa respectively. The models were subjected to a 105N loading, which was applied vertically in relation to the long axis (F1) and 45º obliquely, having two different orientations in relation to the long axis (F2 and F3). The lowest stress values were obtained when the models were subjected to F1. The presence of a restoration in shallow and medium-depth lesions did not promote stress reduction when subjected to F1. However, the stress was reduced in enamel and dentin when subjected to F2 and F3, respectively. A slight stress reduction was observed when deep lesions were restored with RAE and RBE for F1. Also, the stresses in dentin of model V3RAE were reduced for F3 and amplified for F2. These results indicate that the presence of a restoration is not imperative to promote stress reduction in teeth with NCCLs. The direction of occlusal loadings has greater influence on the development and amplification of tensile stresses in enamel and dentin of NCCLs when compared to the type of composite used in the restoration.