Abstract:

Objective　To study the effect of poly D,L-lactic acid (PDLLA) screws with PDLLA-rhBMP compound on bone regeneration in the screwholes and fracture ends of dogmandibles.Methods　Aself-control studywas carried out in 4 dogs. PDLLA/rhBMP-2 compound screws were implanted to fix the mental fractures and PDLLA screws were used as control. The sam- ples from mandibleswere collected at 4, 8, 12, 16 weeks after implantation and observed by radiography and histology.Results　 All dogs showed a greater degree of bone regeneration around PDLLA/rhBMP-2 screws than PDLLA ones and all fractures were fixed and healed well.Conclusion　The PDLLA-rhBMP screwhas a better effect of inducing osteogenesis than PDLLAscrew, and is able to exert a good fixation to fracture.

Key words: poly D,L-lactic acid, recombination human bone morphogenetic proteins-2, internal fixation of fracture, bone induction