Objective: To evaluate the clinical efficacy of a new porcine acellular dermal matrix (PADM) for the treatment of Miller Class I, II, and III multiple gingival recessions using the modified coronally advanced tunnel technique (MCAT). Method and Materials: Twelve nonsmoking, systemically healthy patients presenting at least two adjacent Miller Class I, II, or III gingival recessions (GR), with a minimal depth of 2 mm, were treated consecutively with MCAT in conjunction with PADM. At baseline and 12 months postoperatively, complete root coverage (CRC, eg 100% root coverage), mean root coverage (RC), recession depth, recession width, attached gingiva (AG), keratinized tissue (KT), periodontal pocket depths (PD), and clinical attachment level (CAL) were evaluated. The main outcome variable was CRC. Results: Postoperative healing was uneventful in all cases, without any matrix loss or exposure or infection. Statistically significant improvements (P .0001) were observed 12 months postoperatively in 53 of the included 54 GR (98.15%). Twenty two recessions (40.74%) showed CRC while the mean RC measured 73.20 ± 27.71%. Mean GR reduction was 2.06 ± 1.18 mm while the gain of AG amounted to 0.84 ± 0.73 mm and of KT to 0.69 ± 0.51 mm, respectively. There were no statistically significant changes for PD at 12 months; CAL showed a significant decrease (P .05) at 12 months from 3.77 ± 1.28 mm to 2.30 ± 1.02 mm. Conclusion: PADM in conjunction with MCAT may be successfully utilized for the treatment of Miller Class I, II, and III multiple adjacent GR. Keywords: clinical study, coronally advanced tunnel, gingival recession, porcine acellular dermal matrix, root coverage