title: Evaluation of mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors.
abstract: BACKGROUND
  Several cell types are associated with the development of cystic and tumoral odontogenic lesions. Among inflammatory cells, mast cells can be associated with their pathogenesis. The aim of this study was to analyze mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors.
  
  
  METHODS
  Tissue sections were submitted to toluidine blue staining and immunohistochemistry with antibody anti-tryptase (clone G3). Mast cells were quantitated using Image-Pro Plus software to obtain the mean number of mast cells in three regions: epithelial, superficial portion of the fibrous wall and deep portion of the fibrous wall from 20 periapical cysts, 20 dentigerous cysts (six non-inflamed and 14 inflamed) and 20 keratocystic odontogenic tumors (four non-inflamed and 16 inflamed).
  
  
  RESULTS
  The mean number of mast cells detected per lesion by immunohistochemistry (4.1) was higher than by histochemistry (1.5) (P<0.0001). Inflamed dentigerous cysts and keratocystic odontogenic tumors showed a higher mean number of mast cells than non-inflamed lesions in all regions. The deep region from all cysts showed the highest mean number of degranulated mast cells, except for non-inflamed keratocystic odontogenic tumors analyzed by immunohistochemistry.
  
  
  CONCLUSIONS
  Immunohistochemical staining detected higher number of mast cells than histochemistry. The higher number of mast cells observed in inflamed lesions could indicate the participation of these cells in the inflammatory response in odontogenic lesions. The prevalence of degranulated mast cells in the deep region suggests intense activity of these cells, possibly related to growth of cystic lesions.
authors.affiliation: Department of Oral Pathology, Antonio Pedro Hospital, Federal Fluminense University, Niterói, Rio de Janeiro, Brazil.
authors.forename: Juliana
authors.initials: J
authors.lastname: de Noronha Santos Netto
authors.forename: Fábio Ramôa
authors.initials: FR
authors.lastname: Pires
authors.forename: Eliene Carvalho
authors.initials: EC
authors.lastname: da Fonseca
authors.forename: Licínio Esmeraldo
authors.initials: LE
authors.lastname: Silva
authors.forename: Simone
authors.initials: S
authors.lastname: de Queiroz Chaves Lourenço
mesh_terms: D002452:Cell Count; D015550:Cell Degranulation / Q000502:physiology; D004396:Coloring Agents; D003238:Connective Tissue / Q000473:pathology; D003803:Dentigerous Cyst / Q000473:pathology*; D004848:Epithelium / Q000473:pathology; D005089:Exocytosis / Q000502:physiology; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000473:pathology; D008407:Mast Cells / Q000473:pathology* / Q000502:physiology; D009504:Neutrophils / Q000473:pathology; D009808:Odontogenic Tumors / Q000473:pathology*; D011842:Radicular Cyst / Q000473:pathology*; D014048:Tolonium Chloride; D053802:Tryptases / Q000032:analysis
chemical_list: D004396:Coloring Agents; D014048:Tolonium Chloride; D053802:Tryptases