BACKGROUND Although the use of a subepithelial connective tissue graft (SCTG) in conjunction with a coronally advanced flap (CAF) is a widely performed periodontal procedure, the creation of a partial-thickness flap can incur a risk of perforation or overthinning of the flap itself. Therefore, the aim of the present trial is to compare the efficacies of partial- and full-thickness flap reflections combined with an SCTG. METHODS Twenty patients with Miller Class I or II defects (52 teeth) were selected, and teeth with defects were randomly assigned to the test group (25 teeth) for a CAF and SCTG using a full-thickness flap reflection or to the control group (27 teeth) for a CAF associated with an SCTG and partial-thickness flap reflection. The probing depth (PD), gingival recession (GR), and width of the keratinized tissue (KT) were assessed at baseline and 6 months after surgery. RESULTS The mean root coverage was 97% in the test group (mean reduction in GR: 2.27 ± 1.15 mm) and 95% in the control group (mean reduction in GR: 1.68 ± 0.74 mm). The gain in KT was 0.46 ± 1.47 mm in the test group and 0.49 ± 1.3 mm in the control group, the PD ranged from 1.33 to 1.55 mm in the test group and from 1.31 to 1.64 mm in the control group; no statistically significant difference was found between the two groups for all of these parameters (P >0.05). CONCLUSIONS The elevation of a full- or partial-thickness flap did not appear to influence the amount of KT or the percentage of root coverage achieved post-surgically. More expanded studies are needed to confirm the present findings.