The impossibility to completely eradicate the microorganisms from the oral cavity or from root canals has stimulated the search for new materials that efficiently prevent infections. Chitosan is a biopolymer with a unique chemical structure that renders it with outstanding biocompatibility and easy processing characteristics. The array of applications available is fascinating, as well as poorly understood. The industrial possibilities led to its use in several applications of varied technological interests, and especially in the biomedical area. Furthermore, its anti-oxidant, anti-microbial, anti-inflammatory, wound healing and biofilm inhibiting properties make it especially attractive to be used in the odontological arena. In this review, we address the state of the art on chitosan-based applications for odontology.