Could rhombic-shaped miniplates be applicable for subcondylar fractures of the mandible? A biomechanical study Biomechanical analysis of rhombic-shaped miniplates

Aim: Mandibular condylar process fractures are the most common fractures in the maxillofacial region. Surgical treatment of condylar region fractures with miniplates and miniscrews has become more popular because it is a stable method that allows immediate function. The present study examined sheep hemimandibular subcondylar fracture models to evaluate the biomechanical properties of two different miniplate/screw system types used for surgical fixation of subcondylar fractures. Material and Methods: Experimental standardized subcondylar fracture lines were examined in ten sheep hemimandibula models. Each segment was fixed with one of two fixation types: double straight miniplates with eight miniscrews or a single rhombic-shaped miniplate with five miniscrews. All models were mounted in a servohydraulic testing unit, and a continuous linear force was applied. Maximum force and displacement values were evaluated and statistically analyzed. Results: The rhombic-shaped miniplate group had statistically significantly lower values than the double straight miniplate group for the maximum force, work at maximum load, and hardness. There was no statistically significant difference between the two groups in terms of the displacement at the maximum load. Discussion: Considering the advantages of rhomboid mini-plates, further clinical and mechanical studies are needed for their use in the surgical fixation of subcondylar fractures.