“…Oral lichen planus often develops in the sites of mechanical trauma, for example buccal mucosa (Eisen, 2002;Gorouhi et al, 2014), suggesting a mechanical role in the pathogenesis of oral LP. Given that TRPA1 was upregulated in oral LP lesions (Kun et al, 2016) and that activated TRPA1 plays an important role in mucosal or cutaneous immune reactions (Liu et al, 2013;Oh et al, 2013), we suggest TRPA1 could be activated by mechanical stimuli and evoke oral LP.…”