Resin infiltration (ICON) is indicated for which lesions?

• A. High-viscosity resin infiltrant used to fill cavitated lesions.
• B. Low-viscosity resin infiltrant used to arrest non-cavitated proximal enamel lesions and preserve tooth structure.
• C. Resin cement for crowns.
• D. Composite sealants.

Answer: (B)

Resin infiltration is a minimally invasive approach designed to arrest early caries by letting a low‑viscosity resin penetrate the porous subsurface of an incipient lesion, especially on proximal enamel surfaces. Once the resin infiltrates and is cured, it seals off the lesion, blocking diffusion of acids and nutrients that drive caries progression. This preserves tooth structure by avoiding drilling as long as the enamel surface remains intact and the lesion is non-cavitated. It’s specifically indicated for non-cavitated proximal enamel lesions, where early demineralization is present but cavitation has not occurred. It isn’t used for cavitated lesions, resin cements for crowns, or typical composite sealants, as those have different purposes and require other materials and approaches.