The effect of a collagen membrane in regenerative therapy of two-wall intrabony defects in dogs.

Guided tissue regeneration that supports the periodontal ligament and bone cells in achieving healthy attachment between teeth and alveolar bone following periodontal therapy has been repeatedly described in the literature. The aim of the present study was to assess the effect of an absorbable collagen membrane used in guided tissue regeneration procedures in two-wall intrabony defects. For this purpose, periodontal defects were surgically created around mandibular teeth in nine dogs. In a randomly chosen quadrant in each dog, a collagen membrane was shaped to cover the interproximal bone defect and adjacent root surface. No collagen membrane was placed over the control defects. Block biopsies of test and control sites were obtained from three dogs at 30 days, three dogs at 60 days, and three dogs at 90 days after the procedures. Histomorphologic and histometric evaluations were performed. We observed that both collagen membrane treated and control defects demonstrated similar amounts of new attachment and bone. However, gingival recession and postoperative keratinized tissue loss were observed in most of the sites. Although there was a tendency towards new attachment in both groups, the gingival tissue loss due to recession led to limited regeneration.