The optimal conditions of injection of a chitin gel for applications in periodontal surgery have been studied as a function of various parameters. They correspond to a time of 2 min 15s (+/- 15"). They are achieved for acetylation parameters corresponding to: a molar ratio acetic anhydride/glucosamine residue, R = 1.5, a temperature of the master solution of 12 degrees C, a mixture of hydroalcoholic solution/acetylating reactive stirred for 45s at room temperature and a chitin concentration of 3.6%. This concentration allows us to limit the syneresis. to improve the mechanical properties of the gel and to obtain a viscosity suitable for the injection. Doping of the gel by means of chitosan powder insoluble under these conditions allows us to consider an improvement of the biological activity of the gel.