Abstract
Introduction: In the context of endodontics, oral and periodontal diseases are predictors of various problems, primarily tooth loss in adults. Inflammatory processes are caused by bacteria, genetic factors, lifestyle, and nutrition. Periodontitis can cause alterations and severe damage to oral health and well-being. Numerous clinical and experimental studies highlight a strong association between periodontitis and certain systemic diseases. Objective: It was to conduct a systematic review presenting key clinical studies on the impact of nutrition on oral and endodontic health. Methods: The PRISMA guidelines for systematic reviews were followed. The search was conducted from February to May 2026 across the Scopus, PubMed, Science Direct, SciELO, and Google Scholar databases. Study quality was assessed using the GRADE instrument, and risk of bias was analysed according to the Cochrane tool. Results and Conclusion: A total of 135 articles were identified; 50 were evaluated in full, and 40 were included in this systematic review. Based on the Cochrane risk-of-bias tool, the overall assessment revealed 9 studies with a high risk of bias, while 5 studies failed to meet GRADE and AMSTAR-2 standards. Most studies lacked homogeneity in their results (X² = 75.2% > 50%). This review concluded that nutritional science is essential for oral and endodontic health. Nutrient deficiencies can affect oral health status. Nutritional science addresses nutritional needs and helps prevent diseases associated with a poor diet. A nutrient-deficient diet can accelerate the progression of oral cavity diseases by disrupting tissue homeostasis, reducing resistance to microbial biofilms, and impairing tissue healing, thereby compromising endodontic health and, consequently, systemic health.