AbstractOral health parameters were compared for 6–8 and 10–11‐year‐old children living in neighbouring N. S. W. towns, where the community water supplies consisted of artesian and river water respectively. The demographic characteristics, living pattern and dietary carbohydrate challenge were similar in the two areas and effective oral hygiene practices were uniformly lacking. Children in the artesian water area had 40% lower caries prevalence (DIMFT), 50% less severe carious lesions (SR) and significantly better oral hygiene (OHI) and gingival condition (PI) and correspondingly lesser treatment needs than those supplied by river water. The findings were examined in relation to the concentrations of 10 elements in roof catchment, river and artesian water. Apart from a contribution by fluoride to better oral health, the results implicate lithium as a possible beneficial