Twelve patients with bilateral comparablegingival recessions were treated using a split mouth design, to compare the relative success of root coverage by two regenerative procedures. The areas of recession treated were Class I or II according to Miller's classification and caused either an esthetic problem and/or root sensitivity. The symmetrical defects, on the maxillary canines, 4 mm or deeper, were randomly assigned in each patient to surgical procedures with either a bioresorbable matrix barrier (test) or a non‐resorbable expanded polytetrafluoroethylene membrane (control). Gingival recession, clinical attachment level, probing depth, and extension of keratinized tissue were measured at baseline and at 6 months postsurgically. Both procedures resulted in significant root coverage (P<0.0001) and attachment gain (P<0.0001). The gingival recession decreased from 4.75 ± 0.22 mm to 0.83 ± 0.24 mm and from 4.75 ± 0.22 mm to 0.75 ± 0.22 mm, corresponding to a mean root coverage of 82.4% and 83.2%, at the test and control sites respectively. The average clinical attachment gain was 4.33 ± 0.44 mm at the test sites compared to 4.42 ± 0.48 mm for the non‐resorbable barrier. No significant changes were found for probing depth and keratinized tissue. Data analysis did not demonstrate any significant difference between the two procedures for any of the variables included. However, a questionnaire given to each patient revealed the single‐step surgery to be the patients' choice.J Periodontol 1996;67:7–14.