BIOMECHANICAL ANALYSIS OF THE APPLICATION OF ZYGOMA IMPLANTS FOR PROSTHESIS IN UNILATERAL MAXILLARY DEFECT

Abstract

The objective of this research is to evaluate the biomechanical effect of zygomatic implant-supported obturator prostheses in unilateral maxillary defect. Based on CT data, four 3D numerical models were built. One model was a normal craniofacial complex (model 1) and other three models were structures with unilateral maxilla defect reconstructed using clasp-retained obturator prosthesis (model 2), one zygomatic implant-supported and clasp-retained prosthesis (model 3), two zygomatic implant-supported and clasp-retained prosthesis (model 4). Bilateral vertical loads of 300[Formula: see text]N were imposed and the stress and displacement distribution were calculated, analyzed and compared. The bilateral occlusal forces dispersed along the three-mechanical-pillar of the maxillofacial region and the displacement distributed symmetrically in model 1. Because of mechanical pillars break on the affected side, all occlusal forces were transferred by clasps and abutment teeth in model 2, which induced the increase in stress and displacement level. The zygomatic implant restored mechanical pillars and greatly reduced the stress and displacements levels in models 3 and 4. The stress and displacement distributions on clasps, bones, teeth and periodontal ligaments were more reasonable with the support of zygomatic implants. Therefore, the zygomatic implant-supported and clasp-retained prostheses were found to be more effective for unilateral maxillary defect reestablishment.