Quantification of mast cells in nonreactive and reactive lesions of gingiva: A comparative study using toluidine blue and immunohistochemical marker mast cell tryptase

BACKGROUND: Mast cells (MCs) are immune cells derived from a multipotent CD34 precursor. The most significant identifying feature of MCs is the presence of metachromatic granules. MCs are increased in oral reactive lesions and are possibly involved in pathogenesis of these lesions. OBJECTIVES: 1. To compare the number of MCs between reactive and nonreactive lesions of gingiva using toluidine blue (TB) and mast cell tryptase (MCT) as a specific marker for MCs 2. To compare the staining specificity/efficacy of TB and MCT. METHODOLOGY: The study sample comprised 90 tissues which were divided into three groups: Group A comprised 30 cases of pyogenic granuloma (PG), Group B consisted of 30 cases of gingival hyperplasia (GH) and Group C comprised 30 cases of pericoronitis. Staining was done between 1% TB and immunohistochemistry (IHC) marker MCT. RESULTS: A significant increase in number of MCs was observed in PG as compared to GH and pericoronitis. IHC marker MCT proved to be a more specific marker for MCs compared to TB. CONCLUSION: IHC marker MCT is a specific marker compared to TB. The position of MCs changed from juxtaepithelial in GH to deeper connective tissue in PG which was in correlation with the proliferating tissue that is epithelium in GH and blood vessel in PG.