Connective tissue graft (CTG) is considered as the gold standard for the treatment of gingival recessions (GR). There are few studies assessing the complications that can arise in the donor site when harvesting a connective tissue graft (CTG) and how the harvesting technique can influence those complications. A retrospective clinical study was carried out in order to compare the complications observed in 40 patients with Miller class I, II and III GR ? 3 mm, after using the trap-door technique (TD) in the control group and a newly described technique, the ?UPV/EHU technique?, in the test group. Patients were consecutively allocated to each treatment group. Patients were monitored 14 days after surgery in order to evaluate post-operative complications in the donor site: presence of pain (P), bleeding (B), infection (I) and necrosis > 30%. Although morbidity was observed in both groups, it was less important in the test group (no pain and minimal pain in 30% and 35% of the cases, respectively, and absence of bleeding or infection and necrosis >30% in only 5% of the cases). Within the limits of this study, this newly described ?UPV/EHU technique? should be considered as a treatment option when harvesting a CTG, with minimal morbidity for patients.