The prevalence of gingival recession has been estimated at around 22.5% in people aged older than 29 years. Classic treatment approaches include the use of connective tissue grafts in combination with coronally advanced flaps (CAFs). To reduce morbidity and the need for a secondary surgical site, allograft materials are currently being used. Nevertheless, long-term randomized studies testing the efficacy of these materials are lacking. Hence, the aim of the present randomized controlled clinical trial was to compare two acellular dermal matrix (ADM) materials produced by different processing techniques, freeze-dried (FDADM) and solvent-dehydrated ADM (SDADM). At 12 months, both groups showed significant improvement in attachment level, recession depth, and recession width. A mean imrprovement in attachment level of 2.0 ± 1.08 mm for FDADM and 2.0 ± 0.70 mm for both SDADM was achieved (P = .002). Root coverage after 12 months was 80.66 ± 22.90% for FDADM and 80.97 ± 18.08% for SDADM. Hence, it was concluded that both FDADM and SDADM grafting materials can successfully achieve root coverage in Miller Class I and II recession defects for up to 12 months when used in combination with CAFs.