Mast Cell Activity in Periapical Granuloma and Periapical Cyst Using Toluidine Blue and Astra Blue Stains-A Comparative Histochemical Study
Year: 2026
Type: article
Study design: Observational Study
Abstract: Introduction: Mast cells, comprising up to 29% of the inflammatory cell population, have been reported in periapical granulomas and periapical cysts. Through the release of mediators such as histamine, heparin, tryptase, chymase, and basic fibroblast growth factor, mast cells play a significant role in inflammation and tissue remodeling. Their identification is reliably achieved using metachromatic stains like Toluidine blue and Astra blue. The present study aimed to evaluate mast cell activity in periapical granulomas and periapical cysts using these staining techniques. Objective: 1. To stain the mast cells in Periapical granuloma and Periapical cyst using Toluidine blue and Astra blue stains 2. To compare the staining efficacy of Toluidine blue and Astra blue stains for mast cells. 3. To compare the number of mast cells between Periapical granuloma and Periapical cyst. Materials and Methods: This retrospective Cross-sectional study was conducted in the Department of Oral and Maxillofacial Pathology at Navodaya Dental College and Hospital, Raichur, India, from February 2024 to June 2025. A total of 80 cases (15-50 years) of Periapical lesions comprising 30 cases of Periapical Granuloma and 30 cases of Periapical Cyst. Chronic tonsilitis tissue served as positive controls (10 cases), Cleft lip and palatal tissue served as negative controls (10 cases). Ethical clearance for the study was obtained from the Institutional Ethics Committee. Tissue sections were stained with Toluidine blue and Astra blue for mast cell identification. Mast cells were identified by their metachromatic staining properties and were quantified under light microscopy in representative high-power fields (×400 magnification). and the data were statistically analyzed using ANOVA, followed by post hoc Dunnett’s t-test and unpaired t-test. Results: The mean mast cell counts in periapical granulomas were 52.6 ± 18.1 (Astra blue) and 49.5 ± 19.4 (Toluidine blue), whereas in periapical cysts they were 71.1 ± 31.7 and 69.9 ± 26.5, respectively. Comparison between periapical granulomas and periapical cysts using both stains revealed a statistically significant increase in mast cell count in cysts. Additionally, the mean mast cell count was higher in females than in males, irrespective of lesion type and staining method. Conclusion: On comparison, periapical cysts demonstrated a higher mast cell count than periapical granulomas. Astra blue was found to be more specific for mast cell identification compared to Toluidine blue. The findings of the present study re-emphasize the role of mast cells in the pathogenesis of chronic inflammatory periapical lesions. Clinically, these results suggest that therapeutic strategies targeting mast cell mediators may help modulate inflammation in such lesions.
Institution: Navodaya Dental College and Hospital
Language: English
Subfield: Oral Surgery
Field: Dentistry
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7204086344