Occlusal Loading Effect on Stress Distribution of Endodontically Treated Teeth: Finite Element Analysis Study.

Abstract

Evaluate the influence of occlusal loading on the stress distribution of endodontically treated teeth after root canal preparation with different file's sizes and tapers by means of finite element analysis. Seven three-dimensional models of a single-rooted, single-canal lower second premolar were established, one healthy control and six endodontically treated and restored models. The shape of root canal preparations followed file configurations 30/.05, 30/.09, 35/.04, 35/.06, 40/.04, and 40/.06. Von- Mises equivalent stresses were calculated by applying 30 N, 90 N and 270 N loads to the buccal cusp tip, each one at 90º, 45º and 20º angles from the occlusal plane simulating occlusion, dental interference and laterality, respectively. 45º loading was more prone to formation of higher stress values. The simulation of occlusion and laterality resulted in maximum stress areas located at the inner side of the root curvature, while under occlusal interference they were on the lingual surface over the tooth's long axis. The angulation of occlusal loading and magnitude were determinants for stress distribution on dental structure. Both variations of size and taper were not determinants for the increase in the maximum stress areas.