Which term describes surfaces toward the midline of the mouth?

• A. Occlusal
• B. Mesial
• C. Lingual
• D. Buccal

Answer: (B)

The term describes surfaces toward the midline of the mouth is mesial. The midline is the imaginary line that splits the mouth into left and right halves, so a mesial surface faces toward that line (toward the center of the dental arch). Distal surfaces face away from the midline toward the back of the mouth. Other terms describe different orientations: occlusal surfaces are the chewing surfaces on the tops of the teeth, lingual surfaces face the tongue, and buccal surfaces face the cheek.