The in vitro degradation characteristic of the poly D, L-lactic acid ( PDLIA )/ hydroxyapatite ( HA ) compound were investigated. The compoundfibers were immersed in static phosphate buffer at 37℃ to degrade fo...The in vitro degradation characteristic of the poly D, L-lactic acid ( PDLIA )/ hydroxyapatite ( HA ) compound were investigated. The compoundfibers were immersed in static phosphate buffer at 37℃ to degrade for 22 weeks. The changes in pH value of the buffer solution, the mechanical strength and morphological of inside and outside of composite fibers with degrurlation characteristic were observed. Results show that pH value of the buffer solution stabilized to aboat 7.0 before 12 weeks, however after 20 weeks that pH value quick declined. After 7 weeks that composite fibers of mechanical strength cannot mensuration. SEM observation revealed ttua bimodal degradation occurred in composite fibers.展开更多
Objective To find an ideal biomaterial for internal fixation. Methods Forty rabbits with fracture of the femur diaphysis (superiorcondyle) were treated by intramedullary nailing of femur with composites rod of resor...Objective To find an ideal biomaterial for internal fixation. Methods Forty rabbits with fracture of the femur diaphysis (superiorcondyle) were treated by intramedullary nailing of femur with composites rod of resorbable DL-polylactic acid (PDLLA)-calcium metaphosphate (CMP), while steinmann's pin as control. The fracture healing, the material degradation and its mechanical properties were studied by X-ray films, macroscopic, microscopic and electron microscopic observations. Results No significant inflammatory reaction was found, and all the osteotomies were healed, while material was resorbed. Conclusion The PDLLA-CMP has excellent biocompatibility and mechanical properties, and it can be a promising implant material in orthopaedics surgery.展开更多
文摘The in vitro degradation characteristic of the poly D, L-lactic acid ( PDLIA )/ hydroxyapatite ( HA ) compound were investigated. The compoundfibers were immersed in static phosphate buffer at 37℃ to degrade for 22 weeks. The changes in pH value of the buffer solution, the mechanical strength and morphological of inside and outside of composite fibers with degrurlation characteristic were observed. Results show that pH value of the buffer solution stabilized to aboat 7.0 before 12 weeks, however after 20 weeks that pH value quick declined. After 7 weeks that composite fibers of mechanical strength cannot mensuration. SEM observation revealed ttua bimodal degradation occurred in composite fibers.
文摘Objective To find an ideal biomaterial for internal fixation. Methods Forty rabbits with fracture of the femur diaphysis (superiorcondyle) were treated by intramedullary nailing of femur with composites rod of resorbable DL-polylactic acid (PDLLA)-calcium metaphosphate (CMP), while steinmann's pin as control. The fracture healing, the material degradation and its mechanical properties were studied by X-ray films, macroscopic, microscopic and electron microscopic observations. Results No significant inflammatory reaction was found, and all the osteotomies were healed, while material was resorbed. Conclusion The PDLLA-CMP has excellent biocompatibility and mechanical properties, and it can be a promising implant material in orthopaedics surgery.