GEOMETRIC ANALYSIS OF THE MANDIBULAR FIRST PREMOLAR AND CORRELATION WITH ITS FUNCTIONS USING FINITE ELEMENT METHOD

Introduction: The geometric analysis is of important value for exploring the functional adaptation of the human teeth. The mandibular first premolar is one of the permanent teeth that has unique geometric features to properly perform its functions.

Purpose: To assess the geometric features of the mandibular first premolar functional and the stress analysis of the static occlusal forces using finite element method.

Materials & Methods: Ten human extracted mandibular first premolars were photographed from different aspects to analyze the geometric morphology of the premolars. Dimensional measurements were done by Image J software. Cone beam computerized tomographies were taken to the teeth to construct three-dimensional models for finite element analysis of 150 newtons axial load on buccal cusp tip and distal marginal ridge of each tooth. 

Results: The descriptive and numerical geometric analysis of the images revealed increased lingual inclination and prominence of the buccal cusps in comparison to the lingual cuspsallowing the proper esthetic and masticatory functions. The finite element analysis revealed that there is harmonious stress distribution with relatively high stress concentration in the dentin of the cervical regions of the crowns and roots. The tooth morphology affects the stress distribution.

Conclusion: The mandibular first premolar geometric characteristics are critical toits functional performance. The lingual inclination and the cuspal interrelations are of great importance in the geometric pattern of the mandibular first premolars. The stress distribution is homogeneous in the tooth and supporting tissues with a relative increase in the cervical region.