Investigation of rehabilitation with hybrid prostheses prepared from different materials on pterygoid implants placed in different lengths of atrophic edentulous maxilla by three - dimensional finite element analysis method

Investigation of Rehabilitation with Hybrid Prostheses Prepared from Different Materials on Pterygoid Implants Placed in Different Lengths of Atrophic Edentulous Maxilla by Three - Dimensional Finite Element Analysis Method Treatment of atrophic edentulous maxilla with implants is complicated by problems such as poor bone quality in the posterior region, insufficient bone volume due to long-term edentulousness, and anatomical limitations of the alveolar bone and maxillary sinus. In order to overcome these limitations, a treatment technique with hybrid prostheses has been developed on dental implants placed in the pterygomaxillary region posteriorly and between both maxillary sinuses anteriorly. This treatment technique consists of a full-arch fixed prosthesis supported by 6 implants, 2 posterior and 4 anterior, in the upper jaw. The aim of this study is to examine the stresses created by hybrid prostheses prepared from three different framework materials on implants placed at different lengths in the pterygomaxillary region in the fully edentulous maxilla, using threedimensional finite element analysis method. In the evaluated models, 4 different lengths of implants were placed in the pterygomaxillary region. Implant lengths placed are 11.5 mm. , 13.0 mm. , 15.0 mm. and 18.0 millimeters. Hybrid prostheses are prepared from 3 different framework materials: PEEK, Ti and Zr. Composite was used as aesthetic material in hybrid prostheses prepared from PEEK framework material, porcelain was used as aesthetic material in hybrid prostheses prepared from Ti and Zr framework materials. A force of 150 N was applied unilaterally from the palatal direction to the buccal direction at an oblique 30o angle. According to the results of our study, the use of different framework materials has different effects on prosthetic components and bone. In order to reduce the mechanical complications that can be seen in hybrid prostheses and to obtain a predictable stress distribution in the bone, it is thought that the use of framework materials with high elastic modulus is more appropriate. It has been observed that the change in implant lengths does not make a significant difference on prosthetic components and bone, but further studies are needed on this subject.