Tobacco products are known to cause oral soft-tissue lesions, but they may also directly affect the teeth. Abrasive particles contained in tobacco products may contribute to dental attrition. We studied tobacco samples from 16 brands of cigars, eight brands of snuff, four brands of chewing tobacco and several unprocessed tobacco leaves used as cigar wrappers. Insoluble particulate matter made up about 0.5 percent of the weight of an average tobacco sample.