Which of the following is NOT a tooth surface?

The term "medial" is not recognized as a standard surface descriptor in dental terminology. In dental anatomy, tooth surfaces are typically referred to using established terms that help define their location and function. The correct terminology includes:

• Distal: Refers to the surface of a tooth that is farthest from the midline of the dental arch.

• Occlusal: Relates to the flat surface of the teeth involved in chewing, specifically on the molars and premolars.

• Labial: Describes the surface of the anterior teeth that faces the lips.

Using these established terms allows for clear communication regarding dental anatomy and treatment planning. Since "medial" does not fit into this established set of tooth surface descriptors, it is recognized as the term that does not belong in this context.