What is a furcation?

• A. The apex of a tooth
• B. The enamel surface of a cusp
• C. The periodontal ligament space around the root
• D. The anatomical area of a multi-rooted tooth where the roots divide from the main tooth trunk

Answer: (D)

Furcation is the anatomical area on a multi-rooted tooth where the roots split away from the main tooth trunk. This interradicular region sits between the roots, typically on molars where two or three roots diverge. It is separate from the apex, which marks the tip of a root; it is not part of the enamel surface of a cusp, which is on the crown; and it is not the periodontal ligament space around the root, which surrounds the root within the socket. Clinically, furcation areas are important because bone loss in this space from periodontal disease affects the area between roots and can be challenging to clean and treat; radiographs may underestimate furcation involvement, so probing and careful assessment are essential.