Amnion and Chorion Membranes in the Treatment of Gingival Recession and their Effect on Gingival Biotype: A Clinical and Ultrasonographic Study

Introduction: Treatment of gingival recession defects should aim at addressing both the biological and aesthetic demands. The chances of relapse are minimised if periodontal therapy fulfils the main goal to attain complete root coverage and an increase in the thickness of the keratinised tissue. Aim: To clinically evaluate and compare the efficacy of amnion and chorion membranes in the treatment of gingival recession as root coverage procedures. Further to assess their effect on the gingival biotype. Materials and Methods: Twenty sites in 10 patients with gingival recession defects were selected. These sites were divided into two groups as Group A sites (coronally advanced flap along with the placement of amnion membrane) and Group B sites (coronally advanced flap along with the placement of chorion membrane) according to the treatment modality received. All the subjected sites were assessed for clinical parameters like plaque index, gingival index, probing pocket depth, relative clinical attachment level, position of the gingival margin and the gingival thickness measured by manual and ultrasonographic methods; pre and postoperatively at different intervals. For the intragroup comparisons, 'paired t test' was used and for intergroup comparisons, 'independent t test' was applied. Pearson's coefficient correlation was used for correlation of gingival thickness measured by manual and ultrasonographic methods. For the intragroup comparisons, 'paired t-test was used and for intergroup comparisons independent t-test was applied. A statistical significance p-value was considerd < 0.05. Results: A significant reduction in the plaque index and gingival index scores was seen but statistically no significant difference between the probing pocket depth measured at baseline to six months postoperatively, were observed for both the groups. Amnion group (Group A) showed statistically significant mean gain in relative clinical attachment (p-value=0.01*) and highly significant mean reduction in position of gingival margin (p-value=0.001*) at six months. Chorion group (Group B) showed statistically highly significant mean gain in the relative clinical attachment level (p-value=0.001*) and significant mean reduction in the position of gingival margin (p-value=0.03*) in six months. Both the groups showed statistically high significant mean increase in the gingival thickness measured by both manual and ultrasonographic methods, after six months postoperatively. An improvement in clinical parameters was observed in both the groups but the difference was not statistically significant. Conclusion: The various clinical parameters suggest that both amnion and chorion membranes are biocompatible and safe to use without causing any inadvertent tissue response or antigenic reaction and thus can be used in the treatment of gingival recession defects and to augment the gingival biotype.