In 58 embedded teeth and 126 follicles it was found that the enamel-forming epithelium could be heavily disturbed especially in narrow fissures and at the cemento-enamel junction by premature reduction preventing the enamel from being fully mineralized. The congestion of capillaries in the connective tissue of the follicle caused hemorrhage which imbibed the epithelium and the enamel stroma. In the follicles two types of hyaline bodies could be discerned. One type consisted of hyalinized islands of odontogenic epithelium. They could calcify and constituted a fluent transition to odontogenic tumors, e.g. odontoma and dentinoma. They were PAS positive and elastin negative. The other type (the Rushton type) consisted of white thrombi in congested capillaries in inflamed areas. They were PAS negative and elastin positive. The described mechanism might explain the caries susceptibility in molars and premolars with narrow fissural pits and grooves. The same is valid for the cervical areas when the enamel epithelium is prematurely reduced and the enamel stroma imbibed with hematic material.