The cariostatic effect of betel nut chewing.

The island of Aua 143 miles off the N.E. coast of Papua New Guinea has a population consisting of (41%) Roman Catholics who chew betel nut regularly and (59%) Seventh Day Adventists who do not. This provided an ideal opportunity to compare the effects of betel nut chewing on all aspects of dental health against an identical population who did not chew and therefore provided an excellent control. The results of this survey showed, for those of the population who had never lived away from the island, that for betel nut chewers the prevalence of dental caries was 23% whereas for non-chewers it was considerably and statistically significantly greater at 49%. The amount of dental caries as measured by DMFT was also considerably and statistically significantly greater for this group of non-chewers at 1.162 compared with 0.364 for chewers. The above findings confirmed the work of other investigators which at the time of this survey were not known to the author, and this led to a laboratory investigation of the possibility that the betel nut stain may mediate its effect by acting as a chemical or physical barrier against the acid attack of dental caries. Betel nut stained teeth from PNG, which had been extracted due to periodontal disease were prepared with "windows" of enamel from which the betel nut stain had been removed, and their roots were protected by layers of varnish. These teeth were maintained in an "Artificial Caries Medium" at pH's of 3.5, 4.0 and 4.5 for several months.(ABSTRACT TRUNCATED AT 250 WORDS)