Comparative evaluation of various miniplate systems for the repair of mandibular corpus fractures

Miniplates have been used during the last decade to facilitate stability between bony fragments in the maxillofacial region and are currently the preferred surgical method for the fixation of fractures and osteotomies. The aim of this study was to evaluate and compare the biomechanical behaviors of six different types of miniplates used to reconstruct mandibular body fractures: Group 1 (straight, 2 holes, 12.0 mm spacing), Group 2 (straight, 4 holes, 9.0 spacing), Group 3 (straight, 6 holes, 9.0 mm spacing), Group 4 (L-shaped, 4 holes, 9.0 mm spacing, right hand plate), Group 5 (Y-shaped, 5 holes, 12.0 mm spacing), and Group 6 (double Y-shaped, 6 holes, 9.0 mm spacing). Thirty bovine hemimandibles and a custom-made 3-point biomechanical test frame mounted on a Shimadzu universal test machine were used to evaluate the six different miniplate systems. Results revealed that Group 1 (straight, 2 holes, 12.0 mm spacing) and Group 4 (9.0 mm spacing, right hand plate) had the lowest biomechanical stability, whereas Group 6 (6 holes, 9.0 mm spacing) had the highest biomechanical stability. Group 6 also provided statistically greater resistance to displacement than Group 1 and Group 4.