Which term means toward the midline?

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

Answer: (A)

Toward the midline is described by the term mesial. The midline is the imaginary line that divides the mouth into left and right halves, so anything closer to that line is considered mesial. In practice, the mesial surface of a tooth faces toward the center of the mouth, while the distal surface faces away from the midline toward the back of the mouth. Other terms describe different directions but not toward the midline: buccal means toward the cheek, lingual toward the tongue, and distal moves away from the midline. Remembering that mesial = toward the middle helps you quickly identify surfaces and directions on teeth.