Primary culture of human gingival fibroblasts were grown in Dulbecco's modified Eagle's medium with 10% fetal bovine serum and 1% antibiotics. In experimental group, cells were inoculated in the multiwell plates coated with chitosan in concentration of 0.02, 0.2, and 2 mg/ml. Cell counting and MTT assay were done after 0.5, 1.5, 3, 6 and 24 hours of incubation to evaluate the cell attachment, and then after 2 and 7 days of culture to evaluate the cell proliferation. The alkaline phosphatase activity was measured after 4 and 7 days of culture and the ability to produce mineralized nodules was evaluated after 21 days of culture.

The results were as follows : The morphology of cells on the chitosan-coated well was round or spheric. Round cells were aggregated since 6 hours of culture and showed nodule-like appearance after 24 hours of culture and did not achieved confluency at 7 days. The attachment of gingival fibroblasts was inhibited by chitosan coating with a tendency of dose dependent pattern. But, cellular activity of unit cell was higher than control. The proliferation of gingival fibroblasts was inhibited by chitosan coating at 2 mg/ml(P<0.01), while the cell proliferation at 0.02, 0.2 mg/ml was comparable to the control well. Total alkaline phosphatase activity was inhibited by chitosan coating and decreased in the course of time. While ALP activity of unit cell was the highest at 2mg/ml after 4 days of culture. Finally, gingival fibroblasts produced the mineralized nodule at 2 mg/ml.

In summary, the attachment, proliferation, and alkaline phosphatase activity of gingival fibroblasts were influenced differently by the concentration of coated chitosan. From this study, it could be used as the matrix of tissue engineering for gingiva without inhibition on proliferation of gingival fibroblasts using chitosan at the optimal concentration (0.02mg/ml).