Etiology of caries in Papua New Guinea. The trace element content of urine samples and its relation to individual dental caries experience.

Samples of urine obtained from 10 adult people in each of 10 selected villages in the Sepik district of New Guinea were analysed to determine the levels of 19 elements thought to be of possible relevance to the prevalence of dental caries, judged by the results of previous research. Subjects with dental caries experience could be distinguished from those who are caries-free on the basis of the content of urine samples, as evidenced by the calculation of a statistically significant discriminant function. The elements most likely to be meaningful in relation to such discrimination are molybdenum, magnesium, copper, lead, phosphorus, strontium, and possibly zirconium and potassium. The concentrations of magnesium and phosphorus were significantly correlated with a number of other elements in the samples. Fluorine appears to have a considerable bearing on the output of magnesium, phosphorus, strontium, zinc, and calcium, the first four of which were named above as being major determinants in the discriminant function.