Finite element analysis of adhesive endo-crowns of molars at different height levels of buccally applied load.

This study aimed to evaluate the biomechanical behaviour of adhesive endo-crowns and the influence of their design on the restoration prognosis when four loading positions are applied from the restoration-tooth junction. Two three-dimensional finite element models for the lower first molar were developed: endo-crown as a monobloc and endo-crown of a primary abutment and a full crown. Four crown loading positions were considered: 5, 6, 7 and 8 mm. A force of 1400 N was applied buccally on the middle of the mesiodistal width. No differences were observed for the two endo-crowns concerning restoration displacement and the distribution of equivalent von Mises stress and total equivalent strain. Shifting the position of the applied load to 8 mm resulted in an increase in the displacement from 25 to 42 µm and an increase of equivalent von Mises stress concentration at the tooth. The height of load application on the restoration has a significant role in the prognosis of endo-crowns.