Re-epithelialization of a palatal connective tissue graft transplanted in a non-keratinized alveolar mucosa: A histological and biochemical study in humans

This study was undertaken to evaluate the type of tissue obtained after transplantation of a connective tissue graft, from the same palatal donor site, into a non-keratinized oral mucosa in humans. In 6 human volunteers, a thick palatal epithelio-connective tissue graft was excised, split into two thinner grafts (a thin epithelio-connective tissue graft and a connective tissue graft) and transplanted into controlateral areas lacking keratinized gingiva. The biopsies, excised 3 months post-operatively, were examined using routine histology, immunofluore-scence techniques with different anticy to keratin antibodies and biochemical techniques with non-equilibrium two-dimensional gel electrophoresis. The results show that the epithelio-connective tissue grafts display the histological and biochemical characteristics of keratinized gingiva, whereas the connective tissue grafts expressed features belonging both to keratinized and non-keratinized gingival tissues. It is concluded that the deep palatal connective tissue does not have the full potential to induce non-keratinized epithelial cells to keratinize and that a gingival or palatal connective tissue graft without its overlying epithelium is not likely to yield genuine attached gingiva.