AUTHOR=Qadir Balen Hamid , Mahmood Mohammed Khalid , Rasheed Tara Ali , Othman Kawan Salah , Mahmood Mohammed Abdalla , Abdulghafor Mohammed Aso , Kurda Handren Ameer , Noori Zana Fuad , Tahir Botan Barzan , Fatih Mohammed Taib , Mohammed Fadhil Hevi Nihad , Romao Vincent , Falguiere Arthur , Lan Romain TITLE=Applications of chitosan in oral health and diseases JOURNAL=Frontiers in Oral Health VOLUME=Volume 6 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/oral-health/articles/10.3389/froh.2025.1632233 DOI=10.3389/froh.2025.1632233 ISSN=2673-4842 ABSTRACT=Natural polysaccharides are polymers that are typically made up of over ten monosaccharides connected by glycosidic linkages. Because of their sustainability, renewability, biodegradability, and non-toxicity, natural polysaccharides and their derivatives have found extensive application in the food, pharmaceutical, medical and dental industries in recent years. Chitosan is one of the important members of the natural polysaccharide family with proven antimicrobial, biocompatibility, biodegradability, solubility and film-forming properties. These characteristics make chitosan an excellent candidate for biomedical applications. Chitosan, either alone or in conjunction with other materials, were used in many preclinical and clinical studies related to oral health. There is a growing body of research in these areas indicating its raising trends. The aim of this narrative review is to provide a comprehensive update on the applications of chitosan in various fields of dentistry. To investigate this, PubMed, MEDLINE, Scopus and Embase databases were searched until April 2025. A total of 41 clinical human trials published in the last ten years were included. The contents of these studies were qualitatively and critically assessed. Based on the studies covered in this review, the following conclusions can be drawn: (1) Chitosan is a safe and effective biomaterial for oral and dental applications. (2) Chitosan has been used nearly in all fields of stomatology. (3) Chitosan has been used in the form of gel, solution, scaffold, mouthwash, brush, toothpaste, coating material, intra-canal medicament, sustainable drug release compound, chewing gum, adhesive and varnish. (4) The preliminary research shows promising results. (5) However, at this stage and compared to the established treatment modalities, their utilization in human clinical trials should be viewed as promising supplementary and adjuncts pending further validation through further clinical trials.