Mechanical Effects of Simulated Pressure and Temperature Conditions on Porcelain Dental Bridges Mihai TÂRCOLEA 1, a , Daniel VLĂSCEANU 1,b , Mihai Cosmin COTRUȚ 1,c , Maria Diana VRÂNCEANU 1,d , and Raluca Monica COMĂNEANU 2,e 1 University POLITEHNICA of Bucharest, Bucharest, ROMANIA 2 University TITU MAIORESCU, Faculty of Dentistry, Bucharest, ROMANIA a mihai.tarcolea@upb.ro, b daniel.vlasceanu@upb.ro, c cosmin.cotrut@upb.ro, d diana.vranceanu@upb.ro, e monica.tarcolea@yahoo.co.uk Keywords: Porcelain Dental Bridges, Dental Scanner, STL, FEA, Simulation, Mechanical Effect, Thermal Effect. Abstract. A dental bridge, designed in STL format on a Dental Scanner software, was covered with the porcelain layer in 3-matic Design ©Materialise NV. FEA simulations were made in ANSYS ® Workbench ™ ©SAS, Inc. Firstly, was performed the thermal analysis with the Transient Thermal module, and secondly, the structural static analysis with the Static Structural module. The applied masticatory force was of 300 N, and the studied temperatures were 36°C as reference and, as extremes, 0° and 50°C. The purpose was to determine mechanical effects in the bridge structure for a specific design of the dental bridge geometry in order to optimize its design. Introduction Dental prostheses are subjected to complex effects during mastication, including strains, stresses, thermal variations, and corrosion. Modern dental bridge’s production assumes the existence of a Dental Scanner coupled with a Rapid Prototyping machine for casting model obtaining [1-3]. Dental Scanner software allows for connectors positioning, without any information about their optimal emplacement and the contingent problems created by efforts concentration in the abutments. More than that, applying the porcelain layers can create supplemental efforts concentration. An initial Finite Element Analysis will be an advantage in finding the optimal configuration of the casting model, in order to eliminate as much as possible the concentration of mastication efforts and, in this manner, to allow for a better functionality and a longer lifetime for the dental bridge. Using a combination of the engineering techniques [4,5] with the CAD-CAM dental systems allows for optimization of the design of the prosthetics frameworks for functional and aesthetic oral rehabilitation. The objective of this research is to analyse the strain and stress distribution under a masticatory force of about 300 N, at body temperature and also at extreme possible temperatures of the food (0° and 50°C). There were studied the strain and stress distribution in the metal bridge and in the porcelain layer in order to optimize their design. Methods The STL file of casting model of the metal dental bridge, obtained from the Dental Scanner software, was pre-processed in 3-matic Design in order to build the porcelain layer. So, the parts were discretized in finite elements and the porcelain layer was applied with the option Local Offset. Then the project was exported to ANSYS ® Workbench TM . The imported model had 89685 nodes (42383 for the bridge and 47302 for the porcelain) and 48695 elements (23129 for the bridge and 25566 for the porcelain). ANSYS project was developed in order to allow for Static Structural analysis, and Transient Thermal coupled with Static Structural analysis. The block diagram of the project is presented in Fig. 1. Solid State Phenomena Vol 216 (2014) pp 157-162 Online: 2014-08-18 © (2014) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/SSP.216.157 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, www.ttp.net. (ID: 141.85.110.97-05/05/15,14:32:32)