Tooth Solubility

Question 1

Which mineral component gives teeth and bone their rigidity?

Answer 1

Hydroxyapatite

Question 2

What effect do low pH soft drinks have on teeth?

Answer 2

The can cause dissolution (erosion) of tooth enamel

Question 3

What is a chelating agent? Name an example of a chelating agent.

Answer 3

Chelating agents bind to calcium ions

Citric acid is an example of a chelating agent.

Question 4

Describe tooth erosion and how it differs from dental caries.

Answer 4

Erosion is the direct effect of acids from the diet on teeth, whereas caries involves acids produced by plaque bacteria.

Question 5

How does fluoride reduce dental caries?

Answer 5

Fluoride is incorporated into the hydroxyapatite structure to form fluoroapatite (OH- ions are replaced by F- ions). F- ions are smaller than OH- ions; they fit into the crystal lattice better, rendering it more stable and less soluble in acid.

Question 6

What are 3 ways in which fluoride acts to reduce dental caries?

Answer 6

1. Reduces enamel solubility at low pH
2. Inhibits bacterial metabolism of carbohydrates
3. Promotes enamel remineralisation by saliva