Chitosan is a biopolymer that has a large wound management application and biological proprieties, helping the organisms with fast healing, stimulates the cell proliferation including bacteriostatic and fungistatic particularly useful for wound treatment and as a support material to tissue engineering. The possibilities of application of chitosan are so huge and fascinating as well as not quite discovered. Proprieties of chitosan like biocompatibility, anti inflammatory and others could give promising results in periodontal care or wound healing after teeth extractions. The aim of this work is to review possible applications of chitosan in dentistry area.Keywords: chitosan, biomedical, bioengineering materials, biodegrability, selective permeability, polyelectrolyte action, natural polysaccharide Advances in Tissue Engineering and Regenerative Medicine Research Article Open AccessChitosan-properties and applications in dentistry by 12 Since then several researches with interests in the applications of chitin and aiming to broaden the knowledge about the structural relations and properties of this polysaccharide and its derivatives. 13 Chitosan is a straight chain, cationic polysaccharide that occurs naturally or can be obtained by deacetylation of chitin. Even though there is no nomenclature that definitively guarantees a difference between chitin and chitosan, the term chitosan usually represents cationic copolymers consisting of 2-amino-2-deoxy-β-D-glucose (60-100%) and 2-acetamino -2-deoxy-β-D-glucoside (0-50%), bound together by ß (1→4) bonds. [14][15][16][17] Chitosan is the main derivative of chitin deacetylation in which the mean degree of deacetylation representing the percentage of free NH 2 groups is greater than 60%. 18,19 The average degree of acetylation of chitosan is a measure of the average number of 2-acetamide-2-dexosi-D-glucopyranose and 2-amino-2-deoxy-D-glucopyranose units. The relative percentage of these units has a direct influence on the solubility of chitosan and is an important parameter to determine the average degree of acetylation or indirectly the average degree of deacetylation, which in this way represents the concentration of amino groups, besides exerting a great influence on the physical properties, chemical and biological. 11The amino groups of chitosan are more reactive with respect to the acetamido groups of chitin. The free electron pair of nitrogen in the amino groups is responsible for the adsorption of metallic cations. The average degree of deacetylation determines the fraction of amino groups that are available for interaction with metals. The protonation of amino groups in acid solutions is responsible for the electrostatic attraction of anions. 14 Unlike chitin, chitosan is soluble in dilute acid medium forming a cationic polymer that confers special properties differentiated with respect to the vegetal fibers.11 Chitosan is soluble in dilute acids, such as acetic acid, formic acid, lactic acid, as well as inorganic acids, after prolonged agitation. However,...

Chitosan and its derivatives are polymers with excellent properties to be used in regenerative medicine because they guarantee efficiency in the healing process. This polymer has a great potential for the development of a new generation of biomaterials that can be used in regenerative medicine and tissue engineering. The nanocrystalline chitosan (nCh) is a modified form of chitosan prepared by the method of obtaining chitosan salts. It is characterized by having the same special properties of the precursor chitosan as biocompatibility, bioactivity, be non-toxic and biodegradable. The aim of this study was to develop a new method of obtaining nanocrystalline chitosan according to their chemical and physical characterization. The material was characterized by Absorption Spectroscopy in the Infrared Region -with the Fourier transform (FTIR-ATR), scanning electron microscopy, SEM, Nuclear Magnetic Resonance, NMR, Diffraction of X-rays, particle size analysis and the potential Zeta. The results indicated that the process of obtaining nanocrystalline chitosan did not change the structure of the precursor chitosan. The analysis in the FTIR showed the same functional groups of the precursor chitosan. The 1H-NMR spectroscopy was helpful in the analysis of the chitosan samples in a wide range of values to determine the degree of deacetylation (GD). The morphology indicates the homogeneity of the structure and the surface. The X-ray diffraction shows the reduction of crystallinity of QNC, which corresponds to the amorphous structure thereof. The value of the zeta potential of the chitosan acetate (AQ) in acid media (pH 4.43) was 43.6 mV, while the value of QNC (pH 7.3) was 15.4 mV due to its high polydispersity. The variation in particle size of samples and AQ using QNC 0.450 uM mesh filter, indicated the average particle size of 55.52 and 266.0 nm, respectively.