[Comparison of the stress distribution of microtitanium and bioresorbable plates in fixation of mandibulotomy].

The aim of this study was to compare the stress distribution of microtitanium plate and bioresorbable plates in fixation of mandibulotomy.Three dimensional models of different internal fixation systems in mandibular resection were established, and three dimensional finite element analysis was carried out to compare the displacement changes of fracture segments and stress distribution of titanium plates under the same stress conditions.The maximum stress value of titanium plate was 49.8 MPa, and that of absorbable plate was 4.42 MPa. The maximum stress value of titanium plate was far greater than that of absorbable plate. However, all the stresses were less than their yield limits. It can be seen from the relative displacement comparison that when the mini-titanium plate was fixed on the mandible, the maximum displacement value was 0.1 mm; when absorbable plate was used for fixation, the maximum displacement value was 0.2 mm, and the relative displacement of both plates was small.These results suggest that the stiffness and internal strength of bioabsorbable fixation system are sufficient to support bone healing at the mandible site.