The Effect of Silk Fibroin Particles Coated with Hydroxyapatites on Bone Regeneration in the Rat Calvarial Defect Model

ABSTRACT

PURPOSE: This study evaluated the capability of bone formation of silk fibroin particles coated with hydroxyapatites (HA/SF), as bone graft material when put into the calvarial defect of rats.METHODS: Twenty Sprague Dawley rats were used for this study and round shaped defects were formed in the center of parietal bones (diameter 8.0 mm). The defect was filled with (1) HA/SF (experimental group), or (2) left as a vacant space (control group). The animals were sacrificed at 4 or 8 weeks, postoperatively. The specimens were decalcified and stained with Masson's trichrome for histomorphometric analysis.RESULTS: The average of new bone formation was 33.18+/-3.10% in the experimental group and 20.49+/-5.79% in the control group at 4 weeks postoperatively. That was 42.52+/-7.74% in the experimental group and 25.50+/-7.31% in the control group at 8 weeks postoperatively. The difference between the groups was significantly higher at both 4 weeks and 8 weeks postoperatively (P<0.05).CONCLUSION: The rat calvarial defect was successfully repaired by HA/SF graft. The HA/SF graft showed more new bone formation compared with the unfilled control.