Reverse Engineering and FEM Analysis for Mechanical Strength Evaluation of Complete Dentures: A Case Study

Complete dentures are used in social healthcare of the seniors. These frequently deteriorate, due to the fragility and structural defects of the materials from which are realized, and also due to the accidents produced because of the patients disabilities. The loss of teeth impairs patients’ appearance, mastication ability and speech, thus upsetting the quality of their social and personal life (Mack F., 2005). The selection of materials used in complete dentures technology is crucial, because this directly relates to its performance and life span. Generally, the complete dentures bases are made from acrylic resins – heat curing, light curing, casting, injection, microwaves technologies. Processing technology of these materials sometimes lead to complete dentures with small defects, which can initiate cracks; these are responsible for failure of the complete denture before the expected lifetime. The relative short lifetime of the complete dentures has led researchers to investigate the causes of fracture by studying the stress distribution upon mastication and to find ways to improve their mechanical performance. The finite element method (FEM) has been used for five decades for numerical stress analysis (N. Faur, 2002). The advent of 3D FEM further enables researchers to perform stress analysis on complicated geometries such as complete dentures, and provides a more detailed evaluation of the complete state of stress in their structures.