Finite element analysis of class II mandibular unilateral distal extension partial dentures

Abstract

The current paper aims to investigate the stress distribution developed in Kennedy Class II mandibular distal extension removable partial dentures due to applying a unilateral load condition in both vertical and lateral oblique directions. 3D models of mandible bone and RPD framework were first built based on actual patient data and later exported to ANSYS software to implement the numerical analysis. For realistic analysis, the model considered the frictional contact between the RPD retainers with the teeth and mucosa with the resin denture base by applying the feature of small sliding. To ensure maximum longevity and suitability of restoration, two different metallic RPDs constructed from commercially pure titanium (CP Ti) and cobalt–chromium (Co-Cr) base materials were investigated within the proposed model. It was found that the highest stress value was seen within the Co-Cr framework followed by the titanium framework, particularly within the bar clasp under both loading directions. The principle abutment of the distal extension side carried the highest stress value under both RPD models in both loading cases. Also, it was found that the captured von Mises stress levels within the titanium bar clasps were lower than that in Co-Cr demonstrating both long durability and high flexibility of Ti clasps.

The effect of different framework s material on strain induced in distal abutment in mandibular Kennedy s class II: an in-vitro study

“…The difference in compressibility of the supportive structures in free end saddle cases leads to inevitable tissue ward rotation of the denture. Although actual movement of RPD is minimal, a lever force is created at the terminal abutment leading to an increase in the stress induced [30]. So, proper design and selection of fabrication material is crucial to control stresses induced in the supporting tissues to reduce bone loss [31,32].…”