Development of thermally responsive composite bone plates for maxillofacial trauma treatment

Facial bone fractures in facial injuries resulting from severe trauma can be treated using plate and screw systems. Depending on the location of the fracture, the fracture lines are brought end to end and fixed with plates and screws. Metallic implants are at risk of endogenous infection and there are inherent problems associated with their use, such as stress shielding phenomena, pain, and local irritation. After the bone has healed, a second surgery is needed to remove the metallic fixation. Considering these problems, it is important to use biodegradable plates instead of metal plates. Biodegradable fracture fixation plates degrade slowly in the human body, causing less pain and stress, and there is no need for a second procedure to remove the synthetic material. As these plates decompose, the load will also decrease. There are no toxic and mutagenic effects in an absorbable implant. However, there are some problems with the use of these implants, such as inflammatory response, rapid loss of initial implant strength, higher fracture rates, insufficient hardness of the implants, and weakness compared to metallic implants. In this study, biodegradable plates were designed for use in maxillofacial bone injuries, and treatment plates were prepared using extrusion and injection molding. Different proportions of trimethylene carbonate (TMC), poly-L-lactate (LPLA), poly(D,L-lactate) (DLPLA), polyglycolate (PGA) and beta-tricalcium phosphate (β-TCP) are mixed by extrusion to produce composites by injection molding. Plates were obtained. The degradation, morphological, thermal, and mechanical behaviors of the obtained products were examined.