After randomization a subepithelial connective tissue graft along with coronally advanced flap is applied to one maxillary quadrant to cover the recession.

After randomization platelet rich fibrin membranes along with coronally advanced flap are applied to the other maxillary quadrant to cover the recession.

A coronally advanced flap is applied for recession coverage in the maxilla in a split-mouth randomized trial using a subepithelial connective tissue graft

The measurements of the increase in gingival height (recession coverage) using a linear evaluation (corono-apical direction) with a periodontal probe (Merrit-B; Hu-Friedy, Chicago, IL, USA) at the interventions sites to the nearest 0.5 mm. Registration of the recession height was done before treatment and after 6 weeks.

To assess the shrinkage of the gingival height, the amount of gingival height vestibular to the treated teeth in a corono-apical direction was measured after the surgery and after six months.

This questionnaire used 100 mm visual analog scores VAS to evaluate the amount of pain, ranging from 0 (no pain) to 10 (worst pain imaginable), and the amount of swelling. Patients were asked to fill in the VAS scales at day 7 and day 14 at suture removal. The time of surgery was measured of both treatment options. Timing started at the moment of first incision until the last suture.