Gingiva thickness in guided tissue regeneration and associated recession at facial furcation defects

Consistently successful regenerative therapy for furcation defects using membrane techniques remains a challenge for clinicians. The purpose of this study was to determine if the thickness of tissue used to cover the membrane influences postsurgery recession. Thirty-seven (37) moderate to advanced adult periodontitis patients presenting with at least one mandibular or maxillary molar class 1 or 2 facial furcation involvement participated in the study. Mid-facial presurgery recession was recorded from the cemento-enamel junction to the free gingival margin at a reproducible point. Mid-facial tissue thickness was measured using calipers at a point 5 mm apical to the gingival margin of the mucogingival flap reflected at the time of guided tissue regeneration surgery. Patients were divided into 2 groups based upon tissue thickness measurement. Patients were then re-evaluated for recession at 6 months postsurgery. Sixteen (16) patients with tissue thickness < or = 1 mm demonstrated a mean 2.1 mm increase in recession, while 21 patients with tissue thickness > 1 mm exhibited a mean 0.6 mm increase in recession. We conclude that there is less post-treatment recession (P < 0.01) for tissue thickness > 1 mm than tissue thickness < or = 1 mm. Hence, thickness of gingival tissue covering a membrane appears to be a factor to consider if post-treatment recession is to be minimized or avoided.