Evaluation of the local inflammatory response in secondhand smoker rats with apical periodontitis submitted to adjuvant systemic omega-3 therapy

• Grant number: 22/13553-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2022
• End date: August 31, 2024
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Eloi Dezan Junior
• Grantee: Rodrigo Ribeiro de Camargo
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

Apical periodontitis (AP) is caused by an infection in the root canal system caused by exposure of the pulp by caries, trauma or tooth wear. Smoking is considered a risk factor for periodontal disease and has been associated with failures in endodontic treatments and high prevalence of AP. Omega-3 fatty acids (É-3 PUFAs) have been used as an adjuvant therapy in the treatment of systemic and oral diseases, due to their anti-inflammatory properties. The aim of the present study is to investigate the influence of systemic Omega-3 supplementation on the association between smoking and induced apical periodontitis in rats on the local inflammatory response. Sixty-four animals will be divided into 8 groups (n=8): C (control, rats without PA and without cigarette exposure; PA (rats with induced apical periodontitis); F (rats exposed to cigarette smoke); FPA (rats with induced apical periodontitis and exposed to cigarette smoke); PA+O (rats with induced apical periodontitis supplemented with Omega-3); F+O (rats exposed to cigarette smoke supplemented with Omega-3); FPA+O (rats with induced apical periodontitis exposed to cigarette smoke supplemented with Omega-3), C+O (rats without PA without cigarette exposure supplemented with Omega-3) For inhalation of cigarette smoke, animals (F, FPA, F+ O, FPA+O) will be placed in a smoking chamber for eight minutes, three times a day for 20 days before BP induction. The same procedure will be performed in non-smoking animals (C, PA, C+O, PA+O ), but without the presence of cigarette smoke. On the 5th day of inhalation, the animals in the groups (C+O, PA+O, F+O, FPA+O) will start prophylactic supplementation. a with Omega-3 for 15 days and the control animals (C, PA, F, FPA) will receive distilled water for the same period. On the 20th day, the animals will have the pulp of the first lower right molars exposed to the oral environment for the induction of the periapical lesion (PA), and will remain open for a period of 30 days. During this period, the animals will continue inhaling cigarette smoke associated with therapeutic supplementation for another 30 days, totaling 50 days of smoke inhalation protocol and 45 days of Omega-3 supplementation. At the time of euthanasia, blood will be collected for laboratory blood analysis and the jaws will be removed and processed for histopathological analysis of the severity of the inflammatory profile by staining in Hematoxylin and Eosin (HE). Inflammatory (TNF-a) and anti-inflammatory (IL-10) activity will also be evaluated. The data obtained will be tabulated and subjected to statistical analysis with a significance level of 5%.