Comparison of Free Gingival Graft and Linear Incision Techniques to Obtain Connective Tissue Graft in the Treatment of Multiple Gingival Recessions: a 12-month Non-inferiority Randomized Trial

A randomized controlled non-inferiority trial will be conducted with 24 individuals aged 18 or older, who are periodontally healthy and require root coverage in bilateral multiple RT1-type recessions involving at least two teeth on each side of the mouth. The number of teeth to be covered must be equal on both sides to avoid imbalance in patient-centered comparisons.

Patients included in the study will undergo the bilateral multiple root coverage technique with coronally repositioned flap (Zucchelli and De Sanctis) in both groups. The donor areas for connective tissue will be the hard palate region, with grafts harvested using the linear technique on one side and the free de-epithelialized gingival graft technique on the other side.

Each patient will undergo a preparatory phase for study inclusion, consisting of supragingival scaling, polishing, and oral hygiene instructions at least 3 weeks before study inclusion. Patients will be instructed on personalized and proper use of toothbrush, dental floss, and/or interdental brush.

All surgical procedures in both groups will be performed by the same operator (CCO). Randomization will determine the side to be operated on first. The other side will be operated on after 30 days or until the patient reports complete absence of symptoms in the area of the first surgery to avoid confusion in patient-centered outcomes regarding pain and satisfaction with the techniques.

Outcomes evaluated at 3, 6, 9, and 12 months include: gingival recession depth, probing depth, visible plaque, bleeding on probing, width of keratinized tissue, three-dimensional tissue assessment from intraoral scanning, and quality of life related. Linear and logistic generalized estimating equation models considering the longitudinal nature of the study will be used for data analysis.

INCLUSION CRITERIA Patients aged 18 or older requiring root coverage in bilateral multiple recessions involving at least two teeth on each side of the mouth will be included. The number of teeth to be covered must be equal on both sides to avoid imbalance in patient-centered comparisons. Recessions should be RT1 type according to the 2017 Workshop on the Classification of Periodontal Conditions and Diseases (Jepsen et al. 2018) and without non-carious cervical lesions.

EXCLUSION CRITERIA

Individuals will not be considered eligible if they:

• Present any form of immunological compromise;
• Have diseases or systemic conditions contraindicating surgical procedures or affecting periodontal healing pattern, such as diabetes and autoimmune diseases;
• Present active periodontitis, defined by presence of >=10% subgingival bleeding and probing depth and clinical attachment loss proximal >4mm (Tonetti et al. 2018);
• Are current or ex-smokers;
• Have allergies to ibuprofen and chlorhexidine digluconate.

Research Objective:

PRIMARY OBJECTIVE The overall objective of this study is to compare free gingival graft and subepithelial connective tissue graft in outcomes related to multiple recession coverage.

SECONDARY OBJECTIVE

Compare the two grafts in terms of clinical outcomes of root coverage; Compare the two grafts in terms of digital outcomes of root coverage obtained in scanning and tomography; Compare the two grafts in terms of patient-centered outcomes.