Application of Enamel Matrix Derivative for Tooth Transplantation and Replantation

Objective : The purpose of this study was to clarify the effects of enamel matrix proteins on the regeneration of periodontal ligament (PDL), during transplantation and replantation therapy. Materials and methods : [Exp 1] The crown and root apex of extracted dog teeth were removed and the remaining root separated longitudinally. Two-thirds of crownside PDL and cementum were removed. Prepared teeth were covered with propyleneglycol alginate (PGA) both with and without enamel matrix derivative (EMD) and cultured for 0-14 days. The outgrowth length of the tooth was measured and histological observation done. [Exp 2] The incisal teeth of adult dogs were extracted and 2/3 of crown side PDL and cementum removed. Prepared teeth were treated with PGA containing EMD (EMD group) . No tooth treatment was done in the control group. Following PGA treatment, teeth were replanted. The animals were sacrificed at 2 and 4 weeks after replantation and histological observation performed. Results : [Exp 1] The outgrowth length of the EMD group was longer than that of the other groups. The width of proliferated cell layer on the tooth in the EMD group was thicker. [Exp 2] Ankylosis surface of the EMD group was smaller than that of the control group. In the control group, the region of ankylosis increased longitudinally. In the EMD group, the newly-formed cementum was predominantly cellular cementum. Conclusion : The results suggested that enamel matrix protein enhance the regeneration of PDL and prevent tooth ankylosis in transplantation and replantation therapy.