Chemical and physical oral findings in a case of anorexia nervosa and bulimia.

The deleterious effect on enamel of continual acid challenge from regurgitation of gastric contents in bulimic subjects is well documented. No previous reports, however, have been published on chemical and physical measurements of teeth from such subjects, or on the importance of fluoride in maintaining their dentition. Teeth were obtained from a deceased anorexic and bulimic patient. Shortly before death this patient had saliva analyses and in vivo enamel biopsies at our clinic, before and after a 3-week regimen of daily rinsing with 0.05% NaF. After 4 years of daily regurgitation there was an almost normal thickness of the enamel surfaces typically "at risk", i.e. the palatal surfaces of the maxillary anterior teeth, with normal hardness measurements 10 micron away from the outer surface. SEM micrographs showed an irregular topography, with crystalline deposits rich in calcium, phosphate and fluoride. These surfaces were more reactive to uptake of additional fluoride when given as a daily rinse, than the more protected, and therefore, presumed unaffected surfaces. Our findings suggest that frequent and meticulous oral hygiene measures can substantially minimize the erosive effect on tooth enamel of gastric contents in bulimic patients, especially if fluoride products are used regularly.