Which of the following is a radiographic carious lesion type that involves the facial-lingual surfaces?

• A. Proximal
• B. Facial-Lingual
• C. Occlusal
• D. Recurrent

Answer: (B)

Identifying caries by the surface involved on radiographs. A lesion that affects the facial (buccal) or lingual surfaces is described as facial-lingual caries, which are lesions on the smooth outer surfaces of a tooth rather than between teeth or at restoration margins. This category contrasts with proximal caries (between teeth), occlusal caries (on the chewing surfaces), and recurrent caries (at restoration margins). On radiographs, facial-lingual lesions show up as radiolucencies along the outer aspects of the crown or root once dentin is involved, though they can be harder to detect early than proximal lesions. Therefore, facial-lingual caries best fits a radiographic lesion on the facial or lingual surfaces.