Numerical modeling of the edentulous mandible with different mucosa thickness and resiliency using multiblock method

In spite of numerous studies on biomechanics of the mucous membrane supported dentures, satisfactory determination of the mucous membrane loads is still lacking. The aim of this study was to evaluate the effect of different mucosa thickness and resiliency on stress distribution of complete denture using a three-dimensional finite element analysis. A edentulous mandible with complete denture was converted into a numerical model based on 3D measurements performed by an advanced topometric sensor digitizer (ATOS). This model was transformed into the desired coordinate system and resilient layers were modeled. In each group, mucosa assumed three characteristics of thickness (1, 3 and 5 mm) corresponding to the resiliencies hard, resilient and soft respectively. Evaluation was performed on NASTRAN software with 300N vertical load applied on central incisor teeth. The analyses were based on the maximum and minimum principal stress and displacement values in the supporting tissues. In this study, it was observed that stress decreased at the supporting tissues as mucosa thickness and resiliency increased. The total displacement values increased as the thickness and resiliency of mucosa increased for all structures. Based on the numerical results, the maximum stress values were concentrated in cortical bone.