BACKGROUND Many surgical techniques have been shown to be effective in correcting gingival recessions by covering the exposed root with soft tissue; however, the thickness of the gingival tissue over the root surface probably plays an important role in preventing the recurrence of tissue recession. The aim of the present study was to compare the results of a mucogingival bilaminar technique (BT), guided tissue regeneration (GTR), and a combined periodontal regenerative technique (CPRT) in achieving root coverage and increasing the gingival thickness 1 year after surgical treatment. METHODS In 45 systemically healthy, non-smoking patients aged 33.6 +/- 4.3 years with no periodontal pockets >4 mm, a Miller's Class I or II gingival recession was treated for root coverage: 15 patients underwent BT (connective tissue with partial-thickness double pedicle graft), 15 GTR by a bioabsorbable membrane, and 15 CPRT by a collagen membrane and collagen-incorporated hydroxyapatite. Before and 1 year after surgical treatments, the following clinical parameters were recorded: gingival recession (GR), probing depth (PD), clinical attachment level (CAL), keratinized tissue width (KT), and gingival thickness (GT); the percentage of root coverage was also calculated and the data were statistically analyzed. RESULTS All 3 techniques yielded significant improvements in terms of GR decrease, CAL and KT gain, and GT increase compared to baseline values. Mean root coverage was 90.0%, 81.01%, and 87.12% in BT, GTR, and CPRT groups, respectively. Complete root coverage was observed in 60%, 40%, and 53.3% of subjects from the BT, GTR, and CPRT groups, respectively. No significant differences were observed among the 3 techniques in GR or CAL improvements; however, BT produced a significantly (P<0.01) greater increase of KT, and BT and CPRT groups showed a significantly (P<0.01) greater increase of GT compared to the GTR group. CONCLUSIONS BT, GTR, and CPRT successfully treated gingival recession defects, obtaining comparable percentages of root coverage, but BT and CPRT created a thick gingival tissue significantly greater than that achieved with GTR.