What reduces or removes the fluoride-rich layer of enamel at the surface?

What reduces or removes the fluoride-rich layer of enamel at the surface?

• A. Prophy paste
• B. Fluoride varnish
• C. Toothbrush bristles
• D. Mouthwash with fluoride

Answer: (A)

When fluoride interacts with enamel, a very thin fluoride-rich surface layer can form. That outermost layer is susceptible to mechanical removal, so it can be reduced or wiped away by abrasion. Prophy paste used during professional polishing contains abrasive particles that gently wear away that outermost surface, effectively thinning or removing the fluoride-rich layer. In contrast, fluoride varnish adds fluoride and creates a protective film on the enamel rather than removing material, while mouthwash with fluoride or brushing mainly cleans and adds fluoride rather than removing the surface layer.

When fluoride interacts with enamel, a very thin fluoride-rich surface layer can form. That outermost layer is susceptible to mechanical removal, so it can be reduced or wiped away by abrasion. Prophy paste used during professional polishing contains abrasive particles that gently wear away that outermost surface, effectively thinning or removing the fluoride-rich layer. In contrast, fluoride varnish adds fluoride and creates a protective film on the enamel rather than removing material, while mouthwash with fluoride or brushing mainly cleans and adds fluoride rather than removing the surface layer.