Periodontal regeneration of a class II furcation defect utilizing a bioabsorbable barrier in a human. A case study with histology.

This case report describes human histologic data of periodontal regeneration following guided tissue regeneration therapy (GTR) with a bioabsorbable barrier composed of polylactic acid. The tooth that was examined was part of a previously published study of the clinical effects of GTR therapy without the use of bone or bone substitutes on Class II furcation defects. Twenty-five months following the surgical procedure, the tooth was extracted for non-periodontal reasons. During this extraction, the bone within the furcation that was treated in the study was luxated with the tooth. At the completion of the study (month 12), the furcation's vertical probing depth had decreased by 2 mm with a 2 mm gain in clinical attachment. The horizontal furcation measurement decreased by 3 mm. Following extraction, the tooth was prepared for light microscopy and sectioned in the mesial-distal plane. Reference notches were not placed in the tooth at the time of surgery as there were no plans to perform histologic analysis in the study. However, using the buccal root prominences and what we interpreted to be root planing marks on the cementum, we were able to demonstrate that complete periodontal regeneration occurred on the root surface that was exposed to the pocket environment prior to surgery. New alveolar bone, cementum, and periodontal ligament were consistently observed throughout the furcation in the areas that demonstrated clinical attachment gain and a decrease in horizontal probing depth. This case report adds to the accumulating evidence of histologic periodontal regeneration following guided tissue regeneration with bioabsorbable polylactic acid barriers.