Mechanical resistance of a mandibular first molar under the influence of different endodontic access cavity design: a 3D finite element analysis study.

Biomechanical properties of a mandibular first molar with different cavity designs [traditional access cavities (TEC-I & TEC-II), ninja access cavity (NEC), conservative access cavity (CEC), truss access cavity (Tr-EC), caries-driven access cavity (Cd-EC), caries-driven truss access cavity (Cd-TrEC)] were compared using finite element (FE) analysis. Models were subjected to three different loads. The highest stress distribution was observed on the enamel surface of the Cd-EC design and the dentin surface of the TEC-II. The stress was mainly concentrated on the lingual root surfaces and in the pericervical area. Enlarging the access cavity significantly increased stress distribution on enamel and dentin.