Bridging Plate Development for Treatment of Segmental Bone Defects of the Canine Mandible: Mechanical Tests and Finite Element Method
de Freitas, Eângela.Perez.; Rahal, S.Canevese.; Shimano, A.Carlos.; da Silva, J.Vicente.Lopes.; Noritomi, P.Yoshito.; El-Warrak, A.Oliveira.; Melchert, A.
Journal of Veterinary Dentistry 33(1): 18-25
2016
ISSN/ISBN: 0898-7564 PMID: 27487652 Document Number: 689962
With regard to the canine mandible, a mistaken concept of application is to assume that systemic plate-bone resistance is provided by the implant so that biomechanical position could be ignored. Because the alveolar border of the mandible is a tensile zone, the plate would ideally be positioned near this area while avoiding important structures. The aim of this study was to develop 2 bridging plates for the treatment of a segmental bone defect of the canine mandible using monocortical screws to avoid damage to the tooth roots and remaining neurovascular structures. Computed tomography images of the heads of 4 dogs (rottweiler, Doberman, boxer, and miniature poodle breeds) were used as models to develop the project. The images were reconstructed in 3-dimensional (3D) format. For each dog breed, 6 mandible prototypes were produced, each with a segmental bone defect in the right mandible. The mandibular reconstruction was performed with pure titanium bridging plate and locking screws. One plate model was developed for medium- and large-breed dogs and another for small-breed dogs. Mechanical testing showed the platemandible system resists the bite forces in all dog breeds. All safety factors were greater than I in the platemandible system for medium- and large-breed dogs and greater than 10 in the plate-mandible system for small-breed dogs. Thus, bridging plates designed with differentiated geometry and monocortical locking screws showed mechanical resistance to support simulated induced bone model defects and were able to support at least 5 times the value of bite force for each evaluated dog.