Australian Dental Council (ADC) Practice Test

The expected decline in tooth decay associated with community water fluoridation is most accurately represented by the range of 30% to 40%. This figure is derived from numerous studies indicating that the introduction of fluoride into community water supplies leads to a significant reduction in dental caries among populations.

Fluoride acts by enhancing the remineralization of tooth enamel, making it more resistant to acidic attacks from bacteria in the oral cavity. This preventive measure is particularly effective in reducing decay in children and can lead to long-term health benefits, including lower rates of dental procedures required for treatment of severe caries.

While some studies may show higher percentages of decay reduction, such as the 90% to 95% range, these figures often refer to specific circumstances or controlled studies rather than general community outcomes. Therefore, it is crucial to rely on the consensus of available evidence which firmly supports the more modest decline of 30% to 40% as the expected outcome of effective community water fluoridation programs.