A self-reinforcing biodegradable implant made of poly(ɛ-caprolactone)/calcium phosphate ceramic composite for craniomaxillofacial fracture fixation

Purpose Biodegradable polymer fixators have been used widely in oral and maxillofacial surgery for fracture management. However, short-comings such as insufficient mechanical strength, inappropriate degradation time, lack of radiolucency, and foreign body reactions during bone remodeling remain. Material and methods In this study, calcium phosphate ceramic (CPC, including tricalcium phosphate [TCP] and tetracalcium phosphate/dicalcium phosphate [TTCP/DCP]) and poly(ε-caprolactone) (PCL) were used to fabricate biodegradable orthopedic fixation devices. Results Different weight ratios of CPC were added to PCL, and the results showed that the PCL/CPC composites had good radiopacity, mechanical properties, and biocompatibility. CPC was transformed into hydroxyapatite when the composites were immersed in simulated body fluid. The PCL/TTCP/DCP composite had a higher compressive strength relative to PCL/TCP after setting, and this self-reinforcing property contributed to the hydration of TTCP/DCP and formation of apatite crystals. Thus, PCL/TTCP/DCP screws were prepared for animal studies. No postoperative mortality or complications were noted 6 months postsurgery. Biodegradation of the PCL/TTCP/DCP screws and newly formed bony tissue around the degraded composites were shown on both micro–computed tomography and histology. No peri-implant bone resorption was noted. Conclusion The self-reinforcing PCL/TTCP/DCP composite can be used to fabricate biodegradable fixators for fracture management in craniomaxillofacial fracture fixation.