Immunohistochemical profile of odontogenic epithelium in developing dog teeth (Canis familiaris).

Tumors of the jaw bones and oral soft tissue are relatively common lesions in dogs. The aim of this study was to find cell markers to differentiate odontogenic epithelium from nonodontogenic epithelium for future research on the pathogenesis and pathology of odontogenic neoplasms in dogs. Keratin 14 and 19 staining was observed in odontogenic and nonodontogenic epithelium, whereas amelogenin and p75 neurotrophin receptor immunoreactivity was observed in certain odontogenic epithelial cells at various stages of development but not in other epithelial cells. Calretinin staining was observed in the alveolar epithelial cells directly overlying the developing tooth germ in 28 of 39 sections (71.8%), as well as the dental laminae in 30 of 35 sections (85.7%) and Serres rests in 24 of 28 sections (85.7%). Focal positivity was detected in the respiratory mucosa, some hair follicles, and fusion epithelium of the palate, but no calretinin staining was observed in other oral epithelial cells; therefore, calretinin has potential to be utilized as a marker to differentiate odontogenic form nonodontogenic epithelium.