Khat chewing and smoking effect on oral mucosa: a clinical study.

Khat (Catha Edulis Forskal) is widely cultivated in Yemen and East of Africa. The habit of chewing tender leaves and twigs of khat is deep-rooted in Yemen. Our study investigates the chronic khat chewing and smoking effect on oral mucosa. The sample (n=79) consists of two main groups, khat chewers (n=54) and control groups (n=25). Khat chewers group is divided into 4 subgroups according to duration of khat chewing and smoking habit. The control group is divided into 2 subgroups according to smoking habit. Whitening with mild corrugation, frictional keratosis and frictional keratosis with mild or sever corrugation were the clinical findings. One hundred percent of clinical findings were present on buccal mucosa of chewing side of both smokers and non-smokers whatever the duration of khat chewing period. On the vestibular and mucobuccal fold mucosa, (100 % and 73.3 %) and (60 % and 43.7 %) of the khat chewers group had clinical findings on chewing side of smokers and non-smokers according to khat chewing duration respectively. There was clinical relationship between these lesions and khat chewing, but not smoking. Khat chewing causes oral white lesions on the chewing side and it is found that smoking, clinically, does not exacerbate such lesions.