Thai dental students' knowledge of the betel quid chewing habit in Thailand.

385 questionnaires submitted by volunteer Thai dental students on the betel quid chewing habit in Thailand were evaluated. Questions related to the composition of the betel quid, general and oral effects as well as sociological aspects. Only 62.6% considered the habit as typical for Thailand. Knowledge about the composition of the betel quid showed that 30% of the students were poorly informed. Only 58.4% thought slaked lime to be part of the quid. Similar results were obtained for some of the questions relating to physiological and oral effects and the percentage of "do not know" answers was about 30%. It was widely accepted that betel quid chewing is more common in the provinces (83.6%) and that it is a habit of older people (92.2%); particularly women (70.7%). 71.2% of the students did not know where to buy a betel quid. The decline of the habit was monitored by the fact that 96.1% of the students' parents did not indulge in chewing the betel quid compared to 38.7% of grandparents who did. 70% of the students were convinced that the habit will totally disappear. The knowledge of the betel quid chewing habit of Thai dental students indicated a number of deficits showing that these do not come in close contact with this habit anymore in their families or societies. Since elderly people still indulge in chewing betel quid, dental education still has to focus on oral and general effects and side-effects such as oral precancer, oral cancer and oral submucous fibrosis.