How does endodontic access cavity design affect the biomechanics of a maxillary premolar?? a finite element analysis...

The aim of this study was to evaluate the effect of different endodontic access cavity designs on biomechanical properties of endodontically treated maxillary premolars under various static loads by finite element analysis method.

Based on cone beam computed tomography data of maxillary first premolar, the models of endodontically treated teeth with traditional access cavity (TEC-I), traditional access cavity with Class-II mesio-occlusal cavity design (TEC-II), conventional access cavity (CEC), ninja access cavity (NEC), caries-driven access cavity (Cd-EC), buccal access cavity (BEC) and bucco-occlusal access cavity (BOEC). Three different static loads which were single-point vertical load (Static I), multi-point vertical load (Static II) and multi-point oblique load (Static III) were applied. The stress distribution and maximum Von Misses stress values were recorded.

For the enamel surface, the stress concentration was seen around the central fossa in Static I, on the marginal edge and palatal tubercle in Static II, and on the palatal cusp tip in Static III loads. For the dentin surface, the stress concentration was observed on pericervical area and buccal root surface in Static I, on all around the root surface in Static II, and on buccal and palatal root surfaces and furcation area in Static III loads. While the minimum stress distribution was detected in control group, followed by NEC and CEC designs, the maximum stress distribution was generally monitored in Cd-EC and TEC-II cavity designs.

The increased tissue loss in maxillary premolars due to endodontic access cavity preparation meant the higher stress distribution on the tooth surface.