Coronally positioned flap procedures with or without a bioabsorbable membrane in the treatment of human gingival recession

Background: A variety of surgical techniques have been used to cover recession type defects. New data have indicated that the outcome of coronally positioned flap procedures may be augmented by supporting the flap with a membrane. Methods: The present study aimed at comparing the clinical outcome following treatment of localized gingival recessions by a coronally positioned flap procedure alone, or combined with a bioabsorbable membrane. Twenty patients with buccal bilateral Miller Class I or Class II gingival recessions in cuspids or premolars participated in the study. The split-mouth design, randomized selection of site treatment, and blind evaluation provided 20 sites in a membrane group and 20 sites in a non-membrane group for examination at baseline, and at 3 months and 6 months postoperatively. Clinical variables included the apical extent of the gingival recession, the width of the recession defect measured at the cemento-enamel junction (CEJ), and the width of keratinized tissue at the recession site as well as probing depth and attachment level. Results: Both treatments resulted in a significant gain (P < 0.0001) of root coverage, amounting to an average of 2.3 mm in the membrane group and 2.5 mm in the non-membrane group at the 6-month evaluation. There was no significant difference between the treatments. Similarly, a significant gain of clinical attachment level was seen in the membrane (1.3 mm; P < 0.001) as well as in the non-membrane (1.5 mm; P < 0.0001) group, but without a significant difference between the groups. The reduction of the recession width from baseline to 6 months was significantly greater (P < 0.01) for the non-membrane (2.3 mm) than for the membrane (1.4 mm) group. Probing depth changes were small and not significant for either of the treatments. When patients were grouped as smokers (8) and non-smokers (12), no significant differences were revealed for any of the response variables. Overall, among the 20 membrane sites, one showed no change while the remaining 19 gained root coverage at the 6-month examination. Five sites obtained coverage to the CEJ. Among the non-membrane sites, all gained root coverage at 6 months and 10 sites showed complete coverage to the CEJ. Conclusions: The coronally positioned flap operation offers a predictable, simple, and convenient approach as a root coverage procedure in Miller Class I and Class II recession defects. Combining this technique with the placement of a bioabsorbable membrane does not seem to improve the results following surgical treatment of such defects.