Cinnamon-induced stomatitis venenata, Clinical and characteristic histopathologic features.

Fourteen new cases of cinnamon-induced stomatitis are reported. Ten of these fourteen cases were first detected on the basis of histopathologic changes, which included hyperkeratosis, chronic lichenoid mucositis with plasmacytic infiltration, and marked chronic perivasculitis. Six cases of false-positive histopathologic findings are presented for comparison. It is recommended that when the histopathologic features described are recognized, cinnamon stomatitis should be considered.