Cross-Sectional Analysis in the US
The most recent study, published in mid-August, used a cross-sectional analysis of Medicaid-enrolled children from 5 states. The study looked at Medicaid claims data for cavities and dental surgery under general anesthesia from 2011 to 2012. It then gauged these against the fluoridation status of water in the county.
They found that for each 10% increase in access to fluoridated water, there was a decrease in cavities of 0.45%. This difference remained when adjusted for other variables.
However, researchers found that the reduction in surgery under general anesthesia was significant in the raw data, but not after adjustment for confounding variables. They therefore concluded that fluoride in a community’s water supply definitely reduced the number of cavities, and might also reduce the number of dental surgeries.