Which premolar may have three cusps?

The mandibular second premolar is the correct choice because it commonly presents with three cusps. This premolar typically has two facial cusps (the buccal and lingual) and one larger lingual cusp, which is a distinguishing characteristic of its morphology. While some mandibular second premolars may exhibit only two cusps (one buccal and one lingual), the three-cusped variant is considered a normal anatomical variation and reflects the premolar's diverse cusp morphology.

In contrast, the maxillary first premolar generally has two main cusps: one buccal and one lingual. The same holds true for the mandibular first premolar, which usually presents with a more simplified cusp structure of just one prominent buccal cusp and a smaller, less pronounced lingual cusp. Maxillary second premolars typically have two cusps as well, similar to the first premolars, and do not exhibit the three-cusp configuration. Understanding these distinct morphological features helps identify the specific characteristics of each tooth type in dental anatomy.