Résumé
The biomechanical prognosis of conventional removable partial denture is questionable in case of patient with few remaining teeth or periodontally compromised teeth. In this case, hybrid telescopic double crown RPD may be a successful treatment alternative. Hybrid telescopic double crown RPD has following advantages over conventional RPD: secondary splinting effect between abutments, more vertical stress direction and more convenient in repairing the denture after extraction of abutment tooth. In this clinical case, patient had deep overbite in anteriors and partially edentulous. The maxilla was restored with hybrid telescopic double crown RPD and the mandible was restored with implants and fixed prostheses. Long-term follow-up and supportive periodontal treatment were performed, and satisfactory results were achieved in terms of function and aesthetics.
Résumé
PURPOSE@#Zirconia has exceptional biocompatibility and good mechanical properties in clinical situations. However, finite element analysis (FEA) studies on the biomechanical stability of two-piece zirconia implant systems are limited. Therefore, the aim of this study was to compare the biomechanical properties of the two-piece zirconia and titanium implants using FEA. @*MATERIALS AND METHODS@#Two groups of finite element (FE) models, the zirconia (Zircon) and titanium (Titan) models, were generated for the exam. Oblique (175 N) and vertical (175 N) loads were applied to the FE model generated for FEA simulation, and the stress levels and distributions were investigated. @*RESULTS@#In oblique loading, von Mises stress values were the highest in the abutment of the Zircon model. The von Mises stress values of the Titan model for the abutment screw and implant fixture were slightly higher than those of the Zircon model. Minimum principal stress in the cortical bone was higher in the Titan model than Zircon model under oblique and vertical loading. Under both vertical and oblique loads, stress concentrations in the implant components and bone occurred in the same area. Because the material itself has high stiffness and elastic modulus, the Zircon model exhibited a higher von Mises stress value in the abutments than the Titan model, but at a level lower than the fracture strength of the material. @*CONCLUSION@#Owing to the good esthetics and stress controllability of the Zircon model, it can be considered for clinical use.