Effect of Photobiomodulation Associated with Hydrocortisone Irrigation for Controlling Inflammatory Manifestations in the Extraction of Impacted Lower Third Molars - A Randomized Clinical Trial.

• Grant number: 24/23105-7
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: August 01, 2025
• End date: July 31, 2028
• Field of knowledge: Health Sciences - Dentistry - Oral and Maxillofacial Surgery
• Principal Investigator: Maria Cristina Zindel Deboni
• Grantee: Laís Albuquerque Fernandes
• Host Institution: Faculdade de Odontologia (FO). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

In oral and maxillofacial surgery, extraction of impacted third molars is a frequent intervention. Common symptoms after extraction of impacted lower third molars are trismus, pain and edema. To reduce postoperative discomfort, several pharmacological approaches have been discussed. Glucocorticosteroids are known to suppress inflammation. Hydrocortisone has glucocorticoid effects, which aid in the release of antiphospholipase proteins and inhibit the release of arachidonic acid, preventing the metabolism of prostaglandins and thromboxanes. Irrigating solutions are used during tooth extractions to contain damage to surrounding tissues and improve visualization of the operated area. A previous clinical trial showed a reduction in signs of postoperative inflammation of third molars when using irrigation with Hydrocortisone solution in the transoperative setting, demonstrating a non-invasive and effective use of topical corticosteroids. Photobiomodulation has major impacts on tissues such as increased cell proliferation, accelerated healing process, tissue regeneration, as well as anti-inflammatory action and pain relief. In addition, the effects of photobiomodulation can be listed as: vasodilation, increased blood flow, stimulation of lymphatic drainage and the activation of fibroblasts and neutrophils in tissues. This study aims to investigate, through an equivalence study, whether photobiomodulation therapy alone is as effective as associated with hydrocortisone irrigation. The mouth opening outcome was considered as primary. The sample size calculation was based on parameters from previous studies, using the formula with 80% power, at https://www.sealedenvelope.com/power/continuous-noninferior/, totaling 64 participants. The research consists of a prospective, randomized, self-controlled, triple-blind clinical trial that will be applied to a sample of normoreactive patients, with need for extraction of included lower third molars, in care by Pós-Graduação em Cirurgia e Traumatologia Bucomaxilofacial da Faculdade de Odontologia da Universidade de São Paulo - São Paulo having already been approved by the Ethics Committee under number: 80503224.9.0000.0075 and registered in the Brazilian Registry of Clinical Trials (RBR-8rwbb77). The random sequence will be generated by www.sealedenvelope.com, with randomization organized by blocks (side block and group block). Participants will be randomly allocated to groups for one of the surgeries and then reversed, ensuring the criteria of a self-controlled, crossover and blind study. An operator, unfamiliar with the surgical procedure, will collect data on mouth opening, edema and pain relief scale, respecting the confidentiality of the randomization performed. The tooth extractions will be performed by a single oral and maxillofacial surgeon at two different times. Before suturing the wound, randomly on one side, the participant will receive transoperative irrigation of saline and hydrocortisone solution. On the contralateral side, you will receive transoperative irrigation with saline. The solution will be prepared by an observer not involved in the procedure. Participants in both groups will receive extraoral infrared laser irradiation and intraoral red laser irradiation under the same parameters. A 21-day memory and metabolism wash-out will be performed between surgeries. The data will be subjected to a normality test to apply the most appropriate statistical test. The JAMOVI 5.3 program will be used, with a level of 5% chosen as statistically significant (p<0.05). If the results show equivalence between the groups, the use of photobiomodulation may be an alternative therapy for controlling mouth opening limitation and other postoperative discomforts, avoiding the use of medications and reducing the chance of side effects. (AU)