Regression of stomatitis nicotina in persons with a long-standing habit of reverse smoking: morphologic evidence of the role of ducts

Abstract

Stomatitis nicotina occurs in reverse smokers and there is evidence to show that it could be a precancerous lesion. But most cases regress and the mucous membrane of the hard palate of reverse smokers ultimately becomes thickened and pigmented. The papules of stomatitis nicotina regress and become flat. These macroscopic changes are most probably due to the keratotic and parakeratotic, partial or complete closure of the ducts which have undergone squamous metaplasia. The obstruction gives rise to atrophy and replacement fibrosis of glands, which results in flattening of the papules. The carcinogens in the tobacco smoke might enter through the openings of the ducts and cause the metaplasia of the ducts.