KRT17 and odontogenic cyst: In contrast to the results of the detailed cytokeratin profiling studies by Aragaki [7] and Tsuji [8] comparing other common odontogenic cysts with OKCs (Fig. 1), many, though not all radicular and dentigerous cysts were not completely negative for CK17, but demonstrated some kind of staining (superficial layer, spinous layer, basal or even focal transepithelial labelling).