Distribution of loads in mandibular implant- supported protheses with different length of cantilever and occlusal coating material

Abstract

The objective this study is the evaluation of the distribution of loads, by method of photoelasticity, of Branemark's protocol in mandibular protheses, with different extensions of cantilever and coating materials for aesthetic prosthesis. Will be made two photoelastic models of edentulous mandible, containing five implants 4.1 with external hexagon (H.E.) in the anterior mandible. In the model I, the implants will be installed at the level of resin, meaning clinically which are positioned at the bone level. For this model will be used the UCLA System to make the metallic structure. For model II, the implants will be installed 2mm below the resin, requiring the indication of micro-unit to compensate for this difference, together with UCLA System. To the beginning of the evaluation method of the distribution of loads will be made the one-screw test and applied torque established in the corresponding screws. Will be analyzed the presence of loads in photoelastic models in all steps of confection of mandibular prothese. With the aid of EMIC Universal test machine, firstly loads will be applied in different sizes of cantilever in the metallic structure, and posteriorly the prosthesis made porcelain and acrylic resin with different sizes of cantilever. With this application of loads will be simulated the chewing and will assess the stress of photoelastic models. By photos and the help of Adobe Photoshop CS5 program in the images obtained will be made stress analysis according to the number of fringes high intensity and to the area of distribution of stresses in the models I and II with metallic structure and prostheses finalized with aesthetic coating. (AU)