OBJECTIVEThe aim of this study was to investigate the features of mast cell subtypes and relationship between mast cells and pathogenesis of oral lichen planus.

METHODSMast cells in the tissue of oral lichen planus were stained with Alcian blue/safranine in order to demonstrate mature and immature mast cells, and the constituent ratio of these two subtypes was calculated. Afterwards, LUZEX-F image pattern analysis system was applied to demonstrate the size of these two subtypes and their morphological features.

RESULTSThe constituent ratio of mature and immature types of mast cells in the tissue of oral lichen planus was significantly different from that in the normal tissue (P < 0.01), and such difference was also demonstrated among different types of this malady, including papule-, net- and erosion-type of oral lichen planus (P < 0.05). There was significant difference between the sizes of mature and immature mast cells (P < 0.01) and also the sizes, amount and distribution of the plasma granules within these two mast cells.

CONCLUSIONIt could be implied that mast cells might play a role in the pathogenesis of oral lichen planus.