Preliminary study on prefabricated mucosal liner in subdermal cavity

Objective To investigate the possibility of prefabricated mucosal liner in subdermal cavity with micro-mucosa and gelatin sponge compound graft.Methods The free buccal mucosa was cutted into particles,the diameter of which is less than 1mm,spread onto the gelatin sponge and then transplant to the subdermal cavity.the experimental group was divided into three subgroups(GroupⅠ,Ⅱand Ⅲ) with area expansion ratio of autogenous micro-mucosa 4:1,8:1 and 16:1 respectively.the skin incision was closed over a silicone sheet to prevent adhesion to the underlying mucosa.The control group was only implanted silicone sheet without mucosa graft.Macroscopy and histological samples by HE and immunohistochemical staining were examined on the 7th,14th,21th days after the grafting.Results All the wounds were not healed completely after one week grafting,though some of the mucosa survived and its epithelial cells grew into the gelatin sponge.And the wound healing rates were different.On the 14th day after grafting,The wound healing rates of groupⅠand Ⅱ were more than 80% and higher than groupⅢ(P0.05).However,there's no obvious difference between group Ⅰ and Ⅱ.All the wound healing rates were more than 90% on the 21th day.The CK were observed with immuneohistochemistry in wound tissue specimens so as to confirm epithelial tissue among all the experimental groups.We could find stratified squamous epithelium on 21th day and the cells presented obvious polarity.The gelatin sponge was not absorbed on the 7th day.We could also find some gelatin sponge exist 3 weeks after grafting.Conclusions The oral micro-mucosa and gelatin spongy graft can survive in the subdermal cavity.The quality of compound graft is best in 3 weeks after grafting.The stratified squamous epithelium is thick,because epithelial cells grew into the gelatin sponge.