Which class of GV Black's classification refers to caries located on the edges of cusps of posterior teeth?

The correct classification for caries located on the edges of cusps of posterior teeth is Class VI. This classification specifically addresses carious lesions found on the cusp tips and incisal edges of anterior teeth.

Class I, on the other hand, pertains to caries that occur in the pits and fissures of posterior teeth, which is quite different from the cusp edge locations referenced in the question. Class III focuses on caries found on the interproximal surfaces of anterior teeth that do not involve the incisal edge, while Class V is related to caries that occur on the gingival third of facial and lingual surfaces of teeth. Each classification in GV Black's system helps dental professionals accurately describe the location of caries, allowing for targeted treatment and proper documentation.