Which description defines inactive caries with surface discontinuity (Score 5)?

• A. Localized surface defect in enamel only; no undermined enamel or softened floor detected.
• B. Caries with deep undermined enamel and softened floor.
• C. Surface is smooth and intact with no defect.
• D. Cavity visible and soft on probing.

Answer: (A)

Inactive caries with surface discontinuity is when you see a small, localized defect on the enamel surface, but there is no undermining of enamel and no softened floor beneath. That combination signals an arrested lesion that isn’t progressing, even though the surface isn’t perfectly smooth. The description that matches this is a localized surface defect in enamel only, with no undermined enamel or softened floor detected. If you had undermined enamel or a softened floor, that would point to an active lesion; a smooth, intact surface with no defect wouldn’t reflect a surface discontinuity at all, and a cavity that feels soft on probing indicates active caries.