Autogenous Bone Graft Associated With Enamel Matrix Proteins in Bone Repair

Abstract

Autogenous bone has been used with success as implants in intrabony defects, because of its biological advantages and osteogenic potential. The objective of this study was to evaluate histological and histometrically the bony repair in intrabony defects after dental extractions in rats with graft of a combination of the enamel matrix protein (EMP) (Emdogain, Strauman USA, LLC, Andover, MA. Headquarters in Basel, Switzerland) and autogenous bone. Male rats (Rattus norvegicus, Wistar variety) weighing from 250 to 300 g were anesthetized and submitted to the extraction of the superior incisive and divided in (a) group with autogenous bone (fragment of bone of the alveolar ridge was grafted inside the alveolus) and (b) group with autogenous bone associated with EMP. The animals were killed on the 7th, 21st, and 42nd day after the extraction. The maxillae were processed to obtain fine sections (5 microm) stained with hematoxylin-eosin. The percentual volume of bone tissue in contiguous areas of the graft was calculated through a counting point system of image. The results showed that the bone fragments grafted in the cervical third of the alveolus developed a progressive osseointegration without foreign-body reaction. The quantification of the bony repair in the areas adjacent to the graft showed that the autogenous bone associated with EMP produced a greater amount of bone (10%-15% by analysis of variance, P = 0.05) in all the studied periods. It was concluded that the autogenous bone associated with EMP grafted in bony defects, immediately after the dental extraction in rats, demonstrated biocompatibility and accelerated the repair of bone defect.