Biomechanical analysis of mandibular body reconstruction using titanium plate / 中国组织工程研究

ABSTRACT

BACKGROUND:Three-dimensional finite element has been widely used in the oral cavity field, but little is reported on the three-dimensional finite element reconstruction of the mandibular body using titanium plate. OBJECTIVE:To study the biomechanical characteristics of reconstructing the mandibular body using titanium plate. METHODS:We established a three-dimensional finite element model of mandibular body defect undergoing reconstruction using bicortical titanium screws and titanium plate. Under the simulated normal occlusion state, a 200 N vertical load was added to the central fossa of the occlusal surface of the right mandible first molar. Then, stress distribution and maximum displacement of the mandible, titanium screw, and titanium plate were analyzed. RESULTS AND CONCLUSION:Under the simulated normal occlusion state, mandible stress was concentrated in the mandibular body and mandibular branch, especial y in the anterior and posterior edges of the mandibular branch and the lower edge of the mandible. The stress in the posterior edge of the mandible was lower than that in the anterior edge of the mandible, and moreover, the contact site between the titanium plate and the mandible also presented a concentration of stress. The maximum stress of the bicortical titanium screws appeared near the screw cap, and the stress was also concentrated at the contact site between the titanium screw and the titanium plate. The maximum stress of the titanium screw at the ascending branch of the mandible was higher than that of the titanium screw at the anterior end of the defect. For the titanium plate, the stress was mainly concentrated at the fixed site of the titanium screws;the peak stress of the anterior and posterior edges of the titanium plate was found at the contact site between the anterior end of mandibular defect and the titanium stress as wel as between the ascending branch of the mandible and the titanium screw. After mandibular body reconstruction using the titanium plate, a displacement was likely to occur at the contact site between the anterior end of mandibular defect and the titanium plate. In conclusion, these findings indicate that mandibular body reconstruction using bicortical titanium screws and titanium plate is relatively stable, but the titanium plate fixed at the anterior part of the mandibular angle is prone to breakage.