Abstract: To establish a threedimensional cultured model of dog periodontal ligament cells(PDLC) , and therefore to evaluate the feasibility of chitosan/tricalcium phosphate(CTCP)as the scaffolds of periodontal tissue engineering．Methods： The CTCP was prepared by freezedrying, and then the dog periodontal ligamentcells cultured in vitro were collected and seeded on CTCP threedimensional scaffold. The PDLCs were identified by immunohistochemistry method. Cell morphology and growth pattern were observed under reverse microscope, and cell proliferation was assayed using MTT method. The cells growth on the scaffolds was observed by scanning electron microscope(SEM)． Results： The PDLCs were identified by positive staining for vimentin and negative for keratin. Growth and proliferation of dog PDLCs of CTCP group was not significantly different from that of the control group. SEM showed the porous structure of the CTCP and the dog PDLCs could adhere well, proliferate adequately and extend excessively on the threedimensional scaffold, secreting 1ots of extracellular atrix． Conclusion： CTCP showed excellent adhesion and good biocompatibility with the dog PDLCs in vitro． It is feasible to use CTCP as scaffold and PDLCs as seed cel1 in periodantal tissue engineering.

Key words: Periodontal ligament cells, Chitosan, Tricalcium phosphate, Threedimentional culture, Tissue engineering