The purpose of this study is to analyze and compare stress distribution on bone screws and plate systems in locking and non-locking screw-plates design in lateral mandibular defects.

Solid mathematical model of mandible was created by three-dimensional finite elements analysis and 25 mm length of lateral resection (L defect) was performed on the model. Models were reconstructed with 2.4 locking and non-locking reconstruction plate system. Each masticator muscles attached to mandible were simulated as direction, attachment area and magnitude on 3D model to compare with reality. The stress formation on bone and hardware system were evaluated.

The stress values on the cortical bone, plate and screw system were higher in conventional plate model than the locking system model. The highest stress values were measured in the proximal segment especially in conjunction with conventional screw system. Furthermore, the distribution of stress on the bone surface was more homogenous in the locking system.

It is evident that the use of the locking system in 25 mm length lateral mandibular defects provides an additional advantage over conventional systems in reconstruction models.