[Design and biomechanical evaluation of obturator prostheses with removable partial denture]

The closed palate and obturator prostheses with bar clasp and attachment retention were designed and modeled for repairing the unilateral defect maxillary, and then they were analyzed using finite element method. Under simulated muscle restriction and masticating force boundary, the strength of four maxillary prostheses, the attachment, base plate, bar clasp, denture, obturator et cetera, were considered, and the stress dimension and tendency of the rest living teeth and prostheses were studied. According to the studies on stress, the optimized structure and biomechanical evaluation have a role in the repairs to maxillary defect. The results of analysis are as follows: The stresses of each part of the prostheses were all in the strength range of the materials. The stress distribution on the rest living teeth and alveolar bone was reasonable; the biting force was effectively transferred by the prostheses. As to the obturator prostheses, the materials properties were similar to those of alveolar bone or a bit lower than those, and the obturator structure filled in the cavum of maxillary bone to increase the touch area in the structure was more reasonable than the palate closed structure. The stress and displacement results of living teeth showed that the attachment retention and obturator prostheses could avoid the stress concentration on living teeth and could benefit the retention and power support.