What are considered the working cusps during mastication?

The working cusps during mastication refer to the cusps of the molars that are primarily involved in the grinding and tearing of food. In the context of this question, the correct identification of these cusps is crucial for understanding functional occlusion during chewing.

The choice highlighting the lingual cusps of the maxillary molars and buccal cusps of the mandibular molars accurately reflects their role. During mastication, these cusps come into contact when the jaw moves in a lateral or protrusive manner, allowing for effective food processing. Specifically, the buccal cusps of the mandibular molars fit into the central fossae of the maxillary molars, which facilitates the grinding motion necessary for mastication.

In contrast, the facial cusps of molars do not typically participate in the grinding process and are not considered working cusps, as their primary role is not in the occlusal function. The lingual cusps of mandibular molars alone do not engage effectively during the masticatory cycle for grinding, as they are more involved in opposing anatomical features and do not provide the optimal leverage or surface area for food breakdown.

Thus, the correct choice encompasses the functional anatomy of mastication, highlighting the specific