Treatment of multiple gingival recessions using volume-stable collagen-based gingival graft substitute impregnated with blood platelet derivative: a split-mouth randomized clinical trial

INTERVENTION: H02.163.876.623 In a sample of 25 individuals, the surgical procedure will comprise two approaches, considering that the same individual will receive an intervention group on one side of the mouth and a control group on the other side: in the intervention group, coronally advanced flap with a volume‐ stable collagen matrix (Fibro‐Gide, Geistlich Pharma, Wolhusen, Switzerland) impregnated with fluid platelet‐rich fibrin on one side of the maxilla and, in the control group, coronally advanced flap with the same collagen matrix without platelet‐rich fibrin on the other side. One clinician with at least 10 years of experience in periodontal surgery will be responsible for the procedures. After local anesthesia with 4% articaine with epinephrine 1:100,000, a flap design with a split (interproximal papilla)–full (until mucogingival junction)–split thickness (beyond mucogingival junction) approach will be employed to treat the multiple recessions without vertical incisions. Briefly, intra‐sulcular incisions will be performed involving at least one tooth mesial and one tooth distal to the teeth with gingival recessions. Oblique incisions will be carried out at the interproximal soft tissues and a split‐ thickness flap will be elevated. Next, a full‐thickness flap will be raised up to the mucogingival junction. Soft tissue will be then mobilized with horizontal incisions beyond the mucogingival junction to relieve muscular tension and allow the coronal advancement of the gingival margin. Root surfaces will be carefully instrumented and the interproximal papilla de‐epithelialized. Following the computer‐generated list, the sealed and opaque envelopes will be opened at this time, and the sides of the maxilla will be randomly assigned to one of the groups of collagen matrix with or without plat CONDITION: C07.465.714.354.750 Gingival recession PRIMARY OUTCOME: Reduction in the recession depth measured in millimeters with clinical periodontal probe from gingival margin to cemento–enamel junction at the mid‐buccal site before surgery and six months after root coverage. SECONDARY OUTCOME: Improvement of the clinical parameters keratinized tissue width, bleeding on probing, probing depth, clinical attachment level, gingival thickness, and gingival phenotype measured with a periodontal probe before surgery and six months after root coverage. Reduction on the patient‐reported outcome measures such as discomfort, pain, swelling, bleeding, and ecchymosis, evaluated by a questionnaire. INCLUSION CRITERIA: Patients requiring root coverage for multiple gingival recessions; of both sides of the mouth; in homologous teeth; in the maxillary aesthetic zone (between teeth 15 and 25); without interproximal involvement; with a minimum of three adjacent teeth in each side of the maxilla should present marginal recession at least one of them with a recession depth equal or over 3 millimeters; patients should be equal or over18 years‐old; present good oral health.