The in vivo caries-inhibiting effect of glass ionomer is associated with what in vitro effect?

• A. caries inhibition in vivo and cytotoxicity in vitro
• B. caries inhibition in vivo and remineralization in vitro
• C. pulp irritation in vivo and cytotoxicity in vitro
• D. no effect in vivo and cytotoxicity in vitro

Answer: (A)

The cariostatic effect of glass ionomer in the mouth is tied to fluoride release that promotes remineralization. In vivo, fluoride from the material helps harden and repair subsurface enamel lesions, slowing or preventing caries progression. When studied in vitro, this same action shows up as remineralization of demineralized enamel or dentin near the material under controlled conditions, such as pH-cycling models that simulate acid attacks. Cytotoxicity observed in cell cultures does not explain the caries-inhibiting effect, since it reflects potential cellular toxicity rather than how the material protects tooth structure. So the best association is caries inhibition in vivo with remineralization in vitro.