MATERIAL and METHODS: A total of 32 male Sprague-Dawley rats were divided into 2 groups (n=16 for each) after the formation of bilateral coronal bone defect, based on the interpositional materials used to prevent re-ossification; the rats were divided into the muscle graft (MG) group and the fascial flap (FF) group. In each group, the other side of the coronal suture served as the control. The rats were sacrificed at postoperative 4 weeks or 8 weeks for histopathological, radiological, and microbiologic investigations.

RESULTS: At postoperative 8 weeks, there was partial reunion in the defects with bony tissue in both the groups; no obvious differences were noted between the groups on radiological examination.The defect content involved bone and fibrous tissue in the MG group and bony bridges and loose connective tissue in the FF group. New bone formation was moderate, marked, and extreme and the reduction in defect size was marked, moderate, and extreme in the MG, FF, and control groups, respectively.

CONCLUSION: Our findings revealed that neither the temporal MG nor the temporal FF were able to achieve complete prevention of re-ossification of the skull bone defects including the coronal suture line; further, neither material was superior to the other. Keywords : Skull bone defects, Craniosynostosis, Muscle graft, Fascial flap, Rat