[The blocking effect of topically subepithelial injected thioproline on experimental oral premalignant lesions].

The purpose of this study is to observe the blocking effect of topically subepithelial injected drug on chemically induced oral precancerous lesion and to prove, on a certain extent, the hypothesis that subepithelial connective tissue could exert great influence on the differentiation of the epithelium. A total of 97 syrian hamster was used as experimental animal. Both buccal pouches of all animals were painted thrice weekly with 0.5% DMBA in acetone for 6 weeks. They were divided into two groups: control group and blocking group. In those animals which received topical injected thioproline for 6 weeks, 45.5% precancerous lesions turned into normal epithelial tissue, whereas those untreated animals developed carcinoma by 100%. The result of experimental study supports the hypothesis that the eventual fate of premalignant epithelium may be determined by effect that the underlying connective tissue is able to exert on it.