Periodontal Conditions of Sites Treated With Gingival Augmentation Surgery Compared With Untreated Contralateral Homologous Sites: An 18-to 35-Year Long-Term Study

Background: The aim of this split-mouth study is to compare long-term (18 to 35 years) periodontal conditions of sites treated with gingival augmentation procedures (GAPs) and untreated homologous contralateral sites. Methods: Forty-seven patients with 64 sites (test group), with lack of attached gingiva associated with recessions, were treated with marginal or submarginal free gingival grafts. Sixty-four contralateral homologous sites (control group), with or without gingival recession (GR) and with attached gingiva, were left untreated. Patients were recalled every 4 to 6 months during follow-up period. GR depth, keratinized tissue (KT) width, and probing depth were measured at baseline (T-0), 1 year after surgery (T-1), during follow-up (10 to 27 years, T-2), and at the end of the follow-up period (18 to 35 years, T-3). Multilevel and regression analyses were conducted. Results: At the end of T3, 83% of the 64 treated sites showed recession reduction (RecRed), whereas 48% of the 64 untreated sites experienced increase in recession. Treated sites ended with gingival margin (GM) 1.7 mm (P = 0.01) more coronal and KT 3.3 mm (P < 0.001) wider than untreated sites. In grafted sites, KT at T-3 remained stable compared with T-1 value (4.1 mm, P < 0.001). Conclusions: Sites treated with GAPs resulted in coronal displacement of GM with RecRed up to complete root coverage, whereas contralateral untreated sites showed a tendency to increase in existing recession or develop new recession during the 18- to 35-year follow-up.