Adjunctive benefit of a xenogenic collagen matrix associated with coronally advanced flap for the treatment of multiple gingival recessions: A superiority, assessor-blind, randomized clinical trial

Aim: To evaluate the superiority of coronally advanced flaps (CAFs) when used in combination with a xenogeneic collagen matrix (CMX) for root coverage of multiple adjacent gingival recessions. Materials and Methods: Participants with at least 2 upper adjacent teeth exhibiting gingival recession depth ≥2 mm were recruited and randomized to CAF with (test) or without (control) CMX, respectively. Mean and complete root coverage, amount of keratinized tissue (KTw), gingival thickness (GThick) and patient-reported outcomes (PROMs) were recorded at baseline, 3, 6 and 12 months. Results: Twenty-four patients providing 61 gingival recessions were analysed. After 1 year, gingival recession depth decreased from 2.3 ± 0.7 to 0.3 ± 0.4 mm in the CAF + CMX group (2.0 ± 0.8 mm meanRC) and from 2.6 ± 1.0 to 0.6 ± 0.3 mm in the control group (2.0 ± 1.1 mm meanRC). No difference was observed between the two groups (p = 0.2023). Nineteen (63%) of the test and 16 (52%) of control defects showed complete root coverage (p = 0.4919). GThick greatly increased in the test group (0.5 mm; 0.2–0.8 mm, 95% CI; p = 0.0057). No difference between the two groups was observed for KTw (p = 0.5668) and PROMs. Conclusion: At 1 year, CAF + CMX provided similar root coverage to CAF alone, but a significant increase in gingival thickness.