How many cusps are typically found on a lower second molar?

The lower second molar typically has four cusps. This includes two buccal (cheek-side) cusps and two lingual (tongue-side) cusps, which are designed to aid in the grinding and chewing of food. The arrangement and number of cusps play a crucial role in the functioning of molars, as their shape and orientation help create a surface area that is effective in breaking down food into smaller pieces. Having four cusps allows for a balance in occlusion (the way teeth fit together) and contributes to the overall stability of the dental arch.

In contrast, other options suggest fewer or more cusps than is standard for a lower second molar. The presence of fewer cusps, as in the options indicating two or three, would not provide enough surface area for effective mastication, whereas five cusps would be atypical and indicative of a different tooth variation or anatomical anomaly. Understanding the typical cusp count aids in dental identification and treatment planning.