AimsThis randomized trial assessed for the first time the efficacy of coronally advanced flap (CAF) followed by micro‐needling (MN) in contrast to CAF with acellular dermal matrix (ADM) on gingival thickness (GT, primary outcome), keratinized tissue width (KTW), clinical attachment level (CAL), probing depth (PD), recession depth (RD), recession width (RW), recession reduction (Rec‐Red), complete root coverage (CRC) and percentage of root coverage (all secondary outcomes) in management of RT1 gingival recession in patients with thin gingival phenotype.MethodsA total of 24 patients (n = 24) with a thin gingival phenotype and single RT1 gingival recession in the aesthetic zone were randomly allocated to test‐ (CAF + MN; n = 12) or control group (CAF + ADM; n = 12). All clinical parameters were evaluated at baseline, 3 and 6 months.ResultsBoth groups independently demonstrated significant gain in GT, RW, RD, CAL, PD, Rec‐Red, CRC and percentage of root coverage, with reduced PI and BOP (p < .05) at 3 and 6 months, without intergroup differences (p > .05). At 6 months, KTW gain was significantly higher in CAF + MN (5.08 ± 0.9 mm) than in CAF + ADM‐group (4.25 ± 1.06 mm; p < .05). Stepwise linear regression model with GT as dependent variable showed that base‐line GT was the only statistically significant predictor for GT with a direct correlation between base‐line GT and GT after 6 months.ConclusionCAF followed by MN could represent a promising graft‐less approach for increasing gingival thickness, comparable to CAF with ADM, with superior keratinized tissue width improvement, in the treatment of RT1 recession defects in patients with thin gingival phenotype.