Effects of enamel matrix derivative on healing of subepithelial atelocollagen grafts in rats

Objective: This study evaluated the effects of enamel matrix derivative, a material recently used for the treatment of periodontal disease, on the healing of subepithelial atelocollagen grafts. Materials and Methods: Fourteen male Wistar rats were used. A silicone container with 4 pillar-shaped holes was implanted beneath the back skin. The 4 holes were respectively filled with atelocollagen, enamel matrix derivative, a mixture of atelocollagen and enamel matrix derivative, and saline as control. The materials were evaluated histologically and immunohistochemically, and the number of capillaries immunostained with anti-alpha-smooth muscle actin or anti-vascular endothelial growth factor antibodies were determined at 1, 2, and 4 weeks. Results: The whole amounts of remaining materials and newly formed tissue in the atelocollagen and the atelocollagen and enamel matrix derivative groups were larger than those in the control and enamel matrix derivative groups at each week studied. The mean number of alpha-smooth muscle actin-positive vessels was greater than the mean number of vascular endothelial growth factor antibody-positive vessels. The mean numbers of both alpha-smooth muscle actin-positive vessels and vascular endothelial growth factor antibody-positive vessels in the enamel matrix derivative group and the atelocollagen and enamel matrix derivative group were greater than those in the atelocollagen group at each week studied. Conclusions: Atelocollagen might contribute to maintaining the volume of implanted materials, while enamel matrix derivative might promote the formation of capillaries and enhance the healing of atelocollagen grafts.