What type of caries is presented here?

• A. Proximal caries
• B. Occlusal
• C. Recurrent caries
• D. Beginning occlusal caries

Answer: (B)

This question tests recognition of caries location on the tooth surface. Occlusal caries occur on the chewing surfaces—the pits and fissures of posterior teeth. The image shows a lesion confined to the occlusal pit/groove, which is typical for occlusal caries, where plaque and bacteria settle in these grooves and demineralize enamel from within the fissures. This differs from proximal caries, which occur on the mesial or distal surfaces between teeth and are often spotted on bitewing radiographs; recurrent caries appear at the margins of an existing restoration or sealant; and beginning occlusal caries would be an incipient, noncavitated enamel lesion inside a fissure rather than a clearly developed lesion in the groove. So the location on the occlusal surface makes occlusal caries the best fit.