ABSTRACT
INTRODUCTION A common problem in dentistry is the need to distinguish between those individuals who suffer from a specifi c condition and those who do not. It may be that the procedure required in order to be sure about the oral health of a patient needs the expertise of a dental specialist. In such a situation there is often a simple, less expensive procedure that a general dental practitioner can perform in order to obtain a good (though not perfect) idea about the likelihood of the patient having this dental health problem. For instance, in checking for the presence or absence of oral cancer, a specialist in oral surgery should be able to give a defi nitive answer, but this would be quite costly in terms of hospital resources and patient time. A simple check-up by a general dental practitioner might reveal unusual ulcers, for instance, justifying a referral of the patient to a dental hospital for further investigations. Patients with no such signs would be able to continue receiving just their routine dental care.
