Guided tissue regeneration with a gelatin and polycaprolactone composite membrane for repairing oral soft tissue defects: A prospective, single-blinded, randomized trial

Clinical trials comparing outcomes of the guided tissue regeneration membrane (TRM), fabricated from gelatin and polycaprolactone via electronspinning technology, with collagen membrane for repairing oral soft tissue defects are lacking. The purpose of this clinical trial was to evaluate the efficacy and safety of TRM compared with collagen membrane in reconstructing oral soft tissue defects. This prospective, single-blinded, randomized, noninferiority trial involved 48 participants with oral lesions who were randomized (1:1) into 2 groups: surgery + TRM or surgery + collagen membrane. The primary endpoint was to establish a noninferiority margin of -10% regarding Grade A healing rates 1 month ±7 days after surgery between groups. Secondary endpoints included instrument performance, Grade A healing rate at 10 ±3 days and 3 months ±7 days after surgery, time to achieve Grade A healing, surgical area satisfaction and wound contraction at 10 ±3 days, 1 month ±7 days, and 3 months ±7 days after surgery. Adverse events were assessed to evaluate the safety of TRM. The independent samples t test was used for continuous variables between groups, and the Fisher exact test or chi-squared test was used for categorical variables (α=.05). The Grade A healing rate was 100% in both groups at 1 month ±7 days after surgery in the full-analysis and per-protocol sets. The 95% confidence interval of the rate difference (0%) was -5% to +5%, within the predefined noninferiority margin of -10%, indicating that TRM was not inferior to collagen membrane. No significant differences in secondary endpoints were found between groups (P>.05). Adverse events rates were also similar between groups (serious adverse events: 3 [12.50%] for TRM and 1 [4.17%] for collagen membrane, P=.609; overall adverse events: 7 [29.17%] for TRM and 4 [16.67%] for collagen membrane, P=.303). TRM demonstrated noninferiority to collagen membrane for reconstructing oral soft tissue defects.