Finite element analysis of maxillary defect reconstruction based on polyetheretherketone meshes
Li Xiaoxue, Hou Xiaowei
The Third Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
Abstract: BACKGROUND: The elastic modulus of polyetheretherketone is close to that of bone tissue, so it can be used as a good orthopedic implant material for repairing jaw bone defects.
OBJECTIVE: To establish the digital models of personalized polyetheretherketone scaffolds with different thicknesses and apertures to analyze Von Mises stress and Von Mises strain distribution by finite element analysis.
METHODS: Jaw cone beam CT data from a patient with maxillary right central incisor tooth loss and maxilla defects were used to establish this digital model. A three-dimensional model of right maxilla defect was reconstructed firstly by mirror image of the contralateral normal maxilla bone. Polyetheretherketone meshes with thicknesses of 0.5 and 0.6 mm were designed, and four apertures were designed for each thickness, which were 0, 0.25, 0.35, and 0.45 mm, separately. A three-dimensional model of the right maxilla defect area repaired by polyetheretherketone mesh implantation was established. 100 N was loaded on the polyetheretherketone mesh corresponding to the alveolar crest for mechanical finite element analysis.
RESULTS AND CONCLUSION: (1) The Von Mises stress was mainly concentrated at the crest of alveolar ridge. The concentrated area of the maximum Von Mises stress of polyetheretherketone mesh obviously reduced with the increase of thickness. The maximum Von Mises stress of polyetheretherketone meshes with different thicknesses increased with the increase of aperture. Among them, the ratio of the maximum Von Mises stress to its yield strength was 0.92 and 0.97 in the polyetheretherketone meshes with no hole and 0.25 mm aperture in the group of 0.6 mm, and > 1 in the other groups. (2) The Von Mises strain was mainly concentrated at the crest of alveolar ridge. The concentrated area of the Von Mises strain of polyetheretherketone meshes reduced with the increase of thickness. When the aperture increased from 0 mm to 0.25 mm, the strain change of the polyetheretherketone mesh was negative. When the aperture increased from 0.25 mm to 0.35 mm and 0.35 mm to 0.45 mm, the strain change of the polyetheretherketone mesh was positive. (3) It is concluded that according to the maximum Von Mises stress analysis, the non-hole and 0.25 mm aperture polyetheretherketone meshes in the group of 0.6 mm met the requirements of mechanical properties. Through the analysis of the maximum Von Mises strain, it was found that the polyetheretherketone mesh with thickness of 0.6 mm and aperture of 0.25 mm was the most stable, and plastic deformation was not easy to occur.
Key words: polyetheretherketone, finite element analysis, biomaterial, biosafety, bone defect, bone repair, scaffold, porous material