Keratins in ameloblastomas, developing tooth oral epithelium and dentigerous cysts

There is remarkably little pertinent information available about the correlation between oral epithelium and the possible role in the etiology of dentigerous cysts and ameloblastomas (benign or malignant). Monoclonal antibodies, the wide spectrum screening type was applied on paraffin section, using the peroxidase-antiperoxidase (PAP) procedure. Seven human embryonic cap, bell-stage teeth with the associated dental lamina and oral epithelium, eleven cases of ameloblastoma including three malignant cases, and seven cases of dentigerous cysts were immunocytochemically studied. Keratin profiles were similar in distribution in ameloblastoma (benign and malignant), the mature oral epithelium and dentigerous cysts. The reaction was strong in the malignant ameloblastoma while the dental organs, thin non-keratinized embryonic oral epithelium and dental lamina displayed negative reaction. Interestingly, certain individual cells revealed negative reaction at the stratified squamous adult oral epithelium. These clear negative cells were also present in ameloblastoma. Since the keratin reaction is related to the development and differentiation of tissues and was negative in the thin non-keratinized epithelium, dental lamina, dental organ but positive in adult epithelium and ameloblastoma, it seems that both dentai organs and dental lamina are the principal origin of ameloblastoma and dentigerous cysts