This study aimed to investigate the biomechanical properties of 60 % carbon fiber-reinforced polyetheretherketone (Cfr-PEEK), which exhibits high mechanical strength and can address the limitations of titanium mini plates used in Le Fort I osteotomy.

Models were created using the FEA method based on tomography images of adult individuals. A 5 mm maxillary advancement was applied to the models following Le Fort I osteotomy. Mini plates made of titanium and 60 % Cfr-PEEK were used. Support was provided by the nasomaxillary and zygomaticomaxillary buttresses to fix a total of four l-shaped mini plates. Oblique loads of 125 N, directed from palatal to buccal, and a total of 250 N compression loads were applied to the central fossa of the premolar and molar teeth in the maxillary model at a 30° angle relative to the long axis of the teeth. Displacement values at the osteotomy line, Von Mises stresses in the mini plate-screws, and principal stresses in the bone were compared.

Examination of stress values in the fixation systems of the models revealed higher stress values in the Cfr-PEEK model compared to the titanium model. However, these stresses did not reach levels that would deform the Cfr-PEEK fixation systems. Stress and displacement values in the bone were lower in the Cfr-PEEK model compared to the titanium model.

According to the findings of our study, Cfr-PEEK represents a viable alternative to titanium for mini plate material in Le Fort I osteotomy, offering biomechanical advantages.