Evaluation of titanium plates and carbon fibre reinforced polymer plates in atrophic mandibular fracture: A finite element analysis

The objective of the present study was to conduct a computational assessment of the biomechanical stability of fixation plates with different thickness, made of titanium alloy and carbon-fiber reinforced polyetheretherkotone (CFR-PEEK) in Class III atrophic mandibular fractures. Class III atrophic mandibular models were constructed with three dimensional finite element models. After simulation of fracture on the left ramus of mandible, plates with different thickness (1.0, 1.5, 2.0 and 2.5 mm) were adapted to models and three locking screw on each side of fracture were used for fixation. For simulation of incisal and molar clenching tasks, vertical displacement of models were restricted in incisal and molar regions. Load was applied to all models via simulation of force vectors for each muscle. Titanium and CFR-PEEK material properties were applied to all plate models respectively. Highest Von Mises stress values were observed for the 1.0 mm plate and values decrease gradually with plate thickness to the 2.5 mm plate. Von Mises stress values of screws and plates were lower in models of CFR-PEEK plates. In buccal cortical bone around the screw that proximal to fracture, physiological limit of compressive stress exceeded in some areas. Compressive stresses around screws were lower in models of CFR-PEEK plates. On the other hand, during both incisal and molar clenching tasks CFR-PEEK plates allow more displacement between bone segments compared with titanium plates. With their young modulus similarity with cortical bone, CFR-PEEK materials seems to be suitable for atrophic mandibular fixation with in the limits of finite element analysis. In spite of current usage of CFR-PEEK materials in the field of orthopaedic surgery, usage of CFR-PEEK materials in the maxillofacial region need further investigation.