Repeated bone repositioning in the growing rabbit calvarium hampers bone segment incorporation

There has been concern among surgeons that multiple extended craniofacial procedures might be detrimental to the viability of the involved skeletal structures. This study aimed to explore the result of repeated bone repositionings in the growing rabbit calvaria. Seven immature rabbits were subjected to a three-stage surgical procedure, implying that four calvarial bone segments were originally harvested and repositioned according to a rotational scheme; after 6 weeks only three of the bone segments were harvested and repositioned and, finally, after an additional period of 6 weeks, two segments were repositioned. The results were evaluated by radiographic, histologic (with a special scoring system), and histomorphometric analysis. It was found that one or two cranioplasties did not markedly affect graft incorporation, but three procedures significantly reduced graft revascularization and integration. The findings are discussed with special reference to syndromic craniofacial disorders.