What does early proximal caries look like on radiographs?

• A. Small radiolucent notch just apical to contact area
• B. Circular radiolucency near occlusal surface
• C. Radiolucent band along cemento-enamel junction
• D. Widened periodontal ligament space

Answer: (A)

Early proximal caries on radiographs shows as a small radiolucent notch just below the contact area between adjacent teeth. Demineralization begins near the contact and starts in the enamel, so the first radiographic clue is a delicate, wedge‑shaped darkening that sits apical to where the teeth touch. On bitewing views this subtle notch is the hallmark sign of initial interproximal decay before it extends deeply into dentin.

Other patterns don’t fit because a circular radiolucency near the occlusal surface would point to occlusal or fissure caries rather than proximal caries, a radiolucent band along the cemento-enamel junction suggests cervical burnout or other non-carious changes, and a widened periodontal ligament space indicates periodontal or traumatic pathology rather than caries.