Anatomical Factors Affecting Root Coverage Outcomes in Mandibular Incisors: A 3-Year Prospective Clinical Study

The primary objective was to evaluate the 3-year outcomes of a coronally advanced flap with connective tissue graft (CAF + CTG) for treating gingival recession defects affecting lower incisors. Additionally, the study aimed to investigate whether anatomical factors related to mandibular incisors influence gingival margin stability 3 years post-surgery.

A prospective study was conducted on 30 patients with single gingival recession affecting mandibular incisors, treated with a trapezoidal CAF + CTG at San Raffaele Hospital (Milan, Italy) between January and May 2021. Clinical parameters, including recession depth (REC), keratinized tissue width (KTW), and marginal tissue thickness (MTT), were recorded at baseline and at the 1-year and 3-year follow-ups. Cone Beam Computed Tomography (CBCT) scans were also utilized to assess bucco-lingual inclination, apical root position, vestibular bone dehiscence, and root prominence.

At the 3-year follow-up, complete root coverage (CRC) was achieved in 52% of treated sites. A statistically significant reduction in REC was observed over the evaluation period. However, no significant differences were found in clinical parameters (REC, KTW, and MTT) between the 1-year and 3-year follow-ups. REC at 3 years was significantly and positively correlated with baseline REC, whereas it was inversely correlated with apical root position. Factors associated with mRC at 3 years were KTW baseline, root prominence, and apical root position.

The findings of this study highlight key site-specific anatomical factors that may negatively influence root coverage outcomes in mandibular incisors, providing valuable insights for predicting treatment success.