Oral manifestations of habitual khat chewing: a case-control study

Khat, or qat (Catha edulis), is a shrub indigenous to Yemen and certain parts of eastern Africa. Chewing the leaves, which have sympathomimetic and euphoric effects, is a popular habit in numerous countries including the Yemenite population in Israel. Khat has potentially significant toxic effects; however, its oral effects have been only sporadically examined and some changes suggested. The aim of this study was to assess the association between habitual Khat use and oral/dental pigmentation, gingival health, and reports of oral dryness.

Forty-seven Yemenite Israeli individuals >30 years old, who chewed Khat at least twice a week for over 3 years, and 55 control subjects were studied. All individuals underwent standard clinical oral examinations for color changes and gingival health.

White changes were significantly more prevalent in the khat chewers, identified primarily at the chewing site (83% vs. 16%). The difference in the prevalence of oral mucosal pigmentation between nonchewing nonsmoking (66.7%) and the khat-chewing (100%) groups was highly significant. The mean gingival index and the depth of periodontal pockets of the khat-chewing subjects were significantly reduced at the chewing side compared with the nonchewing side. Increased gingival recession was recorded on the khat-chewing side. Discoloration of the teeth adjacent to the site of chewing was recorded. Oral dryness occurring 30 minutes after initiating the khat-chewing session was reported by khat users.

Khat chewing may result in a number of changes in the oral mucosa and the dentition. The mechanical and chemical irritation may result in the development of mucosal white lesions and dark pigmentation. Khat chewing may reduce aspects related to risk of gingival and periodontal inflammation, but it appears to be associated with attachment loss at the site of chewing.