Visual examination for caries detection relies on which primary sign?

Correct answer: C. Dark staining in fissures

• A. INCORRECT — Explorer (probe) use alone is not recommended as the primary caries detection method (ICDAS recommends against sharp explorer use in fissures); it is used as an adjunct.
• B. INCORRECT — Deep fissure morphology creates caries risk but is not itself the visual sign of active caries; staining and breakdown are the visual cues.
• C. CORRECT — Visual examination for caries detection relies primarily on identifying DARK STAINING in fissures, white spot lesions, and cavitation. The ICCMS and ICDAS systems emphasize visual-tactile examination, with dark/brown staining in fissures as the key visual indicator of caries.
• D. INCORRECT — Transillumination (FOTI/DIFOTI) is used as a CONFIRMATORY method to detect interproximal caries, not a primary visual examination technique.