Effect of bar material on the biomechanical performance of hybrid dental prosthesis

Abstract

Edentulism is the condition of having no teeth which affects the ability of chewing and reduces the quality of patient's life both physically and psychologically. These problems can be reduced using implant- retained dentures, implant- supported dentures and hybrid prostheses to restore the chewing mechanism. The hybrid prosthesis is suitable for patients suffered bone loss. This prosthesis consists of bar (framework) attached to the copings of the abutments and implants. Acrylic artificial teeth are arranged on the bar and secured with acrylic material. The bar supports the artificial teeth, decreases the number of needed implants and reduces the bone stress. Protocol bars in hybrid prosthesis are usually made of metallic materials such as titanium and gold. The limitations of metal coupled with increasing demands of the patients for metal-free prosthesis led researchers to search for alternatives of metals. Polymers such as PEKK and PEEK have recently been introduced in the dental prostheses to eliminate metallic taste, allergic reactions and the high cost. PEEK properties can be improved by adding others materials such as carbon fibers (CFR-PEEK) or ceramic fillers (Bio-HPP). This paper studies the possibility of using polymers and their composites in the fabrication of bar in hybrid prosthesis as alternative to titanium, by using Finite element model. 3D model of mandible with hybrid prosthesis is constructed and different bar materials (Titanium, CFR-PEEK 30&60%, BIO-HPP, PEKK and PEEK) are stimulated, then the results are extracted and compared together. The simulation results clarify the ability of using the polymers and composites as a bar material. Moreover, CFR-PEEK 60% can be used as alternative to titanium.