Architectural organization of human oral epithelium as visualized by keratin staining pattern in tobacco-associated leukoplakias.

The keratin staining pattern in clinical normal buccal mucosa in smokers and non-smokers and in tobacco-associated leukoplakias histologically characterized by the chevron type of keratinization were studied. No differences in keratin staining pattern were found in normal buccal mucosa in smokers and non-smokers. In the tobacco-associated leukoplakias we found distinct differences in staining pattern between areas overlying connective tissue papillae and epithelial ridge areas indicating a lateral organization of oral epithelium related to the ridge system. It seems possible to explain this pattern in terms of current hypotheses of the proliferative conditions in squamous epithelia as previously studied in detail in the epidermis and tongue filiform papillae. We conclude, that our results confirm the presence of subpopulations of suprabasal and basal cells and support the presence of proliferative units in oral epithelium. Furthermore, smoking does not seem to influence the keratin staining pattern in clinically normal buccal mucosa.