STUDY OF EFFECT ON TEETH OF INTERMITTENT FLUORIDATION OF A COMMUNITY WATER SUPPLY

¹ University of Michigan, Ann Arbor, Mich.

Mouth mirror and explorer examinations were made of the teeth of 894 white children 6 to 17 years of age in the Pulaski elementary and high schools. From Fayetteville schools 542 children served as controls, the municipal water supply of that town containing no trace of fluoride. The dental examinations of the two examiners were similar and standardized, and the impression of the examiners was that the children examined in Pulaski and Fayetteville had similar dietary and economic status.

The data indicate that the children using the water of the Pulaski area have fewer DMF teeth than do the children using the water from the Fayetteville area. The def rate per child of the Pulaski group was found to be 2.48 teeth per child for the 6 to 13 year age group and 3.77 teeth per child in the 6 to 8 year age group. For the Fayetteville group the def rate per child for the 6 to 13 year age group was 3.83, and for the 6 to 8 year age group was 7.21. There was a lower DMF rate per child in those children using the municipal water supply in 1948 with mixed exposure (2.40 for the age group 6 to 17 years of age) and for those using the municipal water supply with a constant exposure (1.52 for the 6 to 17 year age group) than for those using wells or springs with continuous exposure (2.79 for the 6 to 17 year age group).

The municipal water supply of Pulaski, which is Richland Creek, is fed by a system of creeks that flow over and through regions rich in phosphate rock that have a high fluorine (F) content. The intermittent fluoridation of the waters of Richland Creek is caused by the waters flowing through the areas rich in phosphate and the concentration of the fluoride in the water and appears to be related to the amount of water saturation in the ground.

The results of this study indicate that there is a definite relation between the phosphate rock of the area and the fluoride content found in the ground and surface water of the area. The richer the phosphate rock in this area the higher the fluorine content that can be expected in the water.