Mast cells in human odontogenic cysts.

Mast cells are granule-containing cells in mucosal and connective tissues that are known to play a central role in allergic and inflammatory responses owing to pro-inflammatory mediators. Cysts in jaws are among the most common expansive, benign and destructive bone lesions; at some stage they are associated with chronic inflammation. Earlier studies have identified mast cells in odontogenic cysts (OC). We investigated the presence and distribution of mast cells and compared their number in different types of radicular cysts (RC), dentigerous cysts (DC) and odontogenic keratocysts (OKC). Ten cases each of RC, DC and OKC diagnosed clinically and histopathologically were selected and stained with 1% toluidine blue. The greatest number of mast cells/mm(2) was found in RC. The fewest mast cells/mm(2) were found in OKC. The subepithelial zones of all cysts contained more mast cells than the deeper zones.