title: Immunohistochemical Expression of Mast Cell in Oral Reactive Lesions.
abstract: BACKGROUND
  Soft tissue reactive lesions are the most common lesions of the oral cavity. Although many studies have shown the interaction of mast cells with fibroblasts and their participation in fibrosis, the role of mast cells in these lesions is not well understood.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the mast cells (MCs) count in oral soft-tissue reactive lesions including peripheral giant cell granuloma (PGCG), peripheral ossifying fibroma (POF), irritation fibroma (IF) and normal oral mucosa.
  
  
  METHODS
  In this cross-sectional study, 50 samples including IF, PGCG, POF (14 cases for each group) and 8 cases of normal oral mucosa were stained with tryptase antibody through immunohistochemistry. The number of mast cells was counted in 5HPF containing maximum counts for each section stained with tryptase. Statistical analysis including Chi-square test and Tukey test with a significance level of 0.05 were considered.
  
  
  RESULTS
  The number of MCs was found to have increased in reactive lesions compared with normal oral mucosa. MCs count in the POF group was higher than the others.
  
  
  CONCLUSIONS
  These findings suggest a possible role of mast cells in the pathogenesis of reactive oral lesions and induction of fibrous tissues. Chemical mediators released from mast cells might influence other cells, especially fibroblasts, to induce fibrosis.
authors.affiliation: Dept. of Oral and Maxillofacial Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran;
authors.forename: Setareh
authors.initials: S
authors.lastname: Shojaei
authors.affiliation: Dental Research Center, Dept. of Oral and Maxillofacial Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran;
authors.forename: Shokoofeh
authors.initials: S
authors.lastname: Jamshidi
authors.affiliation: Modeling of Noncommunicable Diseases Research Center, Dept. of Biostatistics and Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran;
authors.forename: Ghodratollah
authors.initials: G
authors.lastname: Roshanaei
authors.affiliation: Postgraduate Student, Dept. of Oral and Maxillofacial Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran;
authors.forename: Shirin
authors.initials: S
authors.lastname: Modabbernia
authors.affiliation: General Dentist, Private Practice, Hamadan, Iran;
authors.forename: Bahman
authors.initials: B
authors.lastname: Farzin
keywords: Lesion; Mast Cell; Reactive; Tryptase