Australian Dental Council (ADC) Test 2026 – 400 Free Practice Questions to Pass the Exam

The major reaction that occurs when tooth enamel is exposed to preparations with high fluoride concentration is the formation of fluoroapatite. Fluoride ions can replace hydroxyl ions in the hydroxyapatite mineral structure of enamel, which leads to the conversion of hydroxyapatite into fluoroapatite.

Fluoroapatite is more resistant to acid attack than hydroxyapatite, making it beneficial for dental health. The increased resistance to demineralization helps protect teeth from cavities, especially in individuals who are at higher risk for decay. This process is vital in caries prevention and is a key reason why fluoride is added to various dental products.

While sodium fluoride, calcium fluoride, and stannous fluoride can form under certain conditions, they do not play as direct or significant a role in the context of enamel remineralization as fluoroapatite does. Sodium fluoride and stannous fluoride are primarily used in formulations for topical applications, while calcium fluoride can form in a more complex manner and does not directly enhance the structural integrity of the enamel like fluoroapatite.