Clinical and Immunological Evaluation of Tissue Adhesive vs. Silk Suture for Primary Closure of Surgical Flaps After Mandibular Third Molar Extractions: a Split-mouth Randomized Controlled Trial

Study Design and Participants

This randomized split-mouth controlled clinical trial enrolls patients attending the Department of Oral Surgery, Dental School, University of Turin, who require bilateral surgical extraction of impacted mandibular third molars. During the initial consultation, all participants undergo a comprehensive medical history assessment and clinical examination. Panoramic radiography (orthopantomogram, OPT) is prescribed as the first-level radiographic investigation, followed by cone-beam computed tomography (CBCT) when indicated to evaluate the anatomical relationship between the impacted teeth and adjacent structures. The degree of impaction and the expected surgical difficulty are assessed according to the Pell and Gregory classification. During the same appointment, patients receive detailed information regarding the study protocol and provide written informed consent. Two separate surgical appointments are scheduled at least one month apart.

Eligible participants are healthy adults (≥18 years) of either sex presenting with bilateral partial or complete impaction of mandibular third molars requiring surgical extraction, with comparable clinical and radiographic characteristics on both sides. Participants are required to be willing to comply with the study protocol and postoperative follow-up schedule. Exclusion criteria include age younger than 18 years, absence of bilateral impacted mandibular third molars requiring extraction, inability or unwillingness to attend follow-up visits, pregnancy, smoking, uncompensated systemic diseases, oncologic or hematologic disorders, and any condition known to directly or indirectly affect bone metabolism.

Sample Size Calculation

The sample size is calculated to provide 80% statistical power at a two-sided significance level of 5% (α = 0.05) for detecting differences in postoperative bleeding between the two flap closure techniques. Assuming an effect size (Cohen's d) of 0.675, derived from the study by Ghoreishian et al., a minimum of 18 participants is required for a split-mouth design. To compensate for an anticipated dropout rate of approximately 10%, the recruitment target is increased, resulting in a planned sample of 41 participants completing the study.