Vascular and Bone Changes after a Full Mucoperiosteal Flap Versus Control: A Randomized Split-Mouth Experimental Study

Abstract

The purpose of the present study was to investigate the changes in the vascular bed structure of medullary bone after a full mucoperiosteal flap is elevated. In addition, the 3D microstructure of medullary and cortical bone was studied. Thirteen Sprague Dawley rats were used in a randomized split-mouth design experiment. A full mucoperiosteal flap was elevated on the buccal aspect above the first and second maxillary molars. The flap was then approximated, but not sutured back. The animals were allowed to heal for two weeks prior sacrifice. At the time of sacrifice, the animals were perfused with a barium sulfate based solution. Bone and vasculature were analyzed by micro-CT. Bone remodeling was analyzed through H&E and TRAP staining. There were no differences between the experimental and control sides in bone volume fraction and bone mineral density for the buccal region of interest. There also were no differences in bone mineral density, vessel volume and vessel diameter in the interradicular region of interest. Histological sections showed a decrease in the width of cortical buccal bone, increased osteoclastic activity in the inter-radicular region, and areas of necrotic bone in the experimental group. Elevation of a full mucoperiosteal flap increases osteoclastic activity in the trabecular inter-radicular bone, but has little or no effect on the micro-vascular bed of the inter-radicular region.