Evaluation of mast Cell Density in Periapical Inflammatory Lesions

Periapical lesions develop in response to chronic stimulation of an infected root canal in the periapical tissue. Two of the most common periapical inflammatory lesions are periapical cysts and granulomas. A mast cell is a round to elliptical immune cell that originates from bone marrow stem cells and enters peripheral blood, secreting histamine, heparin, cytokines, and chemokines under the influence of triggers. The present study aimed to evaluate mast cell density in periapical cysts and granulomas.

This descriptive cross-sectional study was performed on 60 samples of periapical inflammatory lesions, including radicular cysts and periapical granulomas. Sections were stained with Giemsa and then the number of mast cells were counted in five random areas of the cyst and granuloma walls. The results were analyzed in SPSS software (version 23) using the Mann-Whitney test. P-value<0.05 was considered statistically significant.

The mean number of mast cells in the radicular cyst (6.073±4/6) was higher than periapical granuloma (4.627±5.4); nonetheless, no significant correlation was found (P =0.174).

The presence of mast cells suggests the major role of these cells in the inflammatory mechanism of periapical lesions. Based on the critical role of these cells in the development and spread of periapical lesions, incorporating therapeutic and pharmaceutical approachs to alter the function of mast cell degranulation may be helpful in arresting inflammation in the early stages or preventing the spread of lesions.