Histopathologic evaluation of mast cells in reticular and erosive oral lichen planus using toluidine blue staining


Nooshin Jalayer Naderi 1 , * , Mehdi Ashouri 2 , Mohammad Eslami 3 , Mitra Nedayee 4 , Mohammad Javad Kharazi Fard 5


1 Associate Professor Department of Oral and Maxillofacial Pathology, Shahed University, Tehran, Iran.

2 Oral and Maxillofacial Pathologis, Research Aclvisor Dental Research , Tehran University of Medical Sciences, Tehran, Iran.

3 Professor Department of Oral and Maxillofacial Pathology, Research Aclvisor Dental Research, Tehran University of Medical Sciences, Tehran, Iran.

4 Dentist, Shahed University, Tehran, Iran.

5 Assistant Professor Department of Estatistics, Research Aclvisor Dental Research, Tehran University of Medical Sciences, Tehran, Iran.


Hormozgan Medical Journal: 19 (1); e87381
Published Online: November 20, 2013
Article Type: Research Article
Received: November 04, 2012
Accepted: November 20, 2013




Introduction: Oral Lichen Planus (OLP) is one of the most common mucocutaneous
lesion, and its etiologic factors have not been elucidated yet. OLP has two different
clinical forms including reticular and erosive. Mast cells function in non-specific
immunology is an etiologic factor involved in the formation of lichen planus. This study
aimed at determining the pattern of mast cells presence in clinical forms of reticular and
erosive oral lichen-planus in basal, epithelial, and superficial connective tissue layers.
Methods: The study population in this retrospective research included archival
histopathological files in Oral and Maxillofacial Pathology Department, Faculty of
Dentistry, Tehran University of Medical Sciences. A total number of 53 paraffinembedded
blocks consisting of 18 reticular and 17 erosive OLP samples were included in
the study. Four-micron sections were prepared for toluidine blue staining. Mast cells were
counted in ten fields of light microscopy at magnification of 400 in epithelial, basal, and
superficial connective tissue layers, and the mean number of mast cells in each layer was
calculated. Mann-Whitney and Friedman tests were used to analyze the data while pvalues
less than 0.05 were considered significant.
Results: The mean number of mast cells was 1.85±2.9 in reticular and 2.02±3.18 in
erosive groups. The mean count of mast cells in epithelial, basal, and connective tissue
layers were 0.23±0.31, 0.34±0.45, and 4.98±3.28, respectively, in reticular lichen planus,
and 0.21±0.25, 0.23±0.38, and 5.53±3.31, respectively, in erosive lichen planus. There
was no significant difference between reticular and erosive forms of OLP and between
epithelium and basal layers in terms of mast cells count (P=0.474, P=0.148,
respectively), whereas a significant difference existed between epithelial and connective
tissue layers (P<0.001).
Conclusion: The number of mast cells in reticular and erosive forms of OLP was higher
in connective tissue than epithelium. Regardless of tissue layer, mast cells count was
higher in erosive than reticular form of lichen planus.


Oral Lichen Planus - Mast Cells - Toluidine Blue

© 2015, Hormozgan Medical Journal. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/) which permits copy and redistribute the material just in noncommercial usages, provided the original work is properly cited.
  • 1. Refrences are included in the PDF.