Abstract
BACKGROUND: Surgical extraction of third molars is a common oral and maxillo-facial surgery procedure frequently associated with postoperative complications, such as pain, swelling, and trismus. Photobiomodulation (PBM), also known as Low-Level Laser Therapy (LLLT), involves the use of low-intensity laser to promote tissue healing, reduce inflammation, and relieve pain. This study evaluated the effectiveness of PBM following surgical extraction of mandibular third molars. MATERIAL AND METHODS: This was a prospective, multicenter, randomized, triple-blind clinical trial conducted across five Italian centers. Seventy-nine patients were randomly assigned to a test group (PBM) or control group (no PBM). PBM was delivered immediately after surgery and on the following two days, using a multiband diode laser (445, 660 and 970nm). Primary outcomes were postoperative pain, facial swelling, and trismus. Secondary outcomes included health-related quality of life and analgesic consumption. Covariates included patient age, gender, the extracted tooth and the impaction classification according to Pell & Gregory and Winter. The time of the surgical procedure, measured in seconds from incision to final suture, was also documented. Descriptive statistics were calculated for all variables. Normality was assessed using the Shapiro-Wilk test, and homogeneity of variances was evaluated using Levene's test. Between-group comparisons for continuous outcomes were performed using Student's t-test or the Mann-Whitney U test, depending on data distribution. Categorical vari-ables were analyzed with chi-square or Fisher's exact test. A p-value< 0.05 was considered statistically significant. RESULTS: No statistically significant differences were found between groups for any of the measured outcomes. However, trends favored the PBM group, particularly regarding reduced pain and improved quality of life. CONCLUSIONS: The study was powered to detect a large effect size (Cohen's d=0.8); therefore, the lack of statistical significance suggests that any true effect, if present, is likely smaller than this threshold. Further studies with larger sample sizes and standardized protocols are needed to explore smaller yet clinically relevant effects.