The Repair of Critical-Size Defect with Fibrin Sealant in Rat Calvaria

ABSTRACT

This study was designed to evaluate the capacity of fibrin sealant to mediate the repair of critical size defects of rat calvaria. Twenty-four rats were randomized into four groups(n=6) and an 8-mm circular calvarial defect was made in each rat. In Group I and II, as control groups, defects were left untreated and evaluated at postoperative 6th and 12th week, respectively. In Group III and IV, defects were treated with fibrin sealant implantation and evaluated at the same point of time as in Group I and II, respectively. Results were examined by gross and histologic findings, simple radiographic study, and radiodensitometric analysis for bony density quantitatively. By gross and simple radiographic findings, animals with fibrin sealant implantation generally showed thick coverage of defects and focal radioopacity within defect area, but non-treated animals showed only fibrous healing. Histologically, small amount of new appositional bone growth was only seen at the edge of the defect at 6th week in Group III, but in Group IV, there are substantial amounts of new immature bone with well-organized patterns within the defect at 12th week postoperatively. In the radiodensitometric analysis, there was no statistically significant difference between Group I and Group III at 6th week. Compared with Group II, however, Group IV showed significant bony healing (p=0.0225) at 12th week. In conclusion, the fibrin sealant appeared to be an effective mediator in bone regeneration of this critical-sized calvarial defect model, but long-term implantation period should be needed for optimal results.