Questions: All of the following conditions are acceptable for enamel microabrasion except: a. mild fluorosis. b. remineralized white spot lesions. c. hypermineralized areas. d. hypomineralized areas.

The answer is the last one (or D): hypomineralized areas.

Explanation for each option:

a. Mild fluorosis: Enamel microabrasion is often used to treat mild fluorosis, which presents as white streaks or spots on the teeth. The procedure can help to remove the superficial enamel layer, thereby reducing the appearance of these spots.

b. Remineralized white spot lesions: These lesions are often the result of early caries that have been arrested and remineralized. Microabrasion can be effective in improving the appearance of these white spots by removing the outer enamel layer.

c. Hypermineralized areas: Hypermineralized areas are regions of enamel with higher mineral content, which can appear as white spots. Microabrasion can be used to smooth out these areas and improve their appearance.

d. Hypomineralized areas: Hypomineralized areas are regions of enamel with lower mineral content, making them softer and more prone to wear and decay. Microabrasion is not suitable for these areas because it involves the removal of enamel, which could further weaken the already compromised enamel structure.

Summary: Enamel microabrasion is not suitable for hypomineralized areas because these areas are already weakened and removing more enamel could exacerbate the problem.