Which radiographic appearance is described for furcation involvement?

• A. Radiolucent area in the furcation region
• B. Widened lamina dura at the furcation
• C. Conical tooth on xray
• D. Normal radiograph

Answer: (C)

Furcation involvement shows up on a radiograph as a radiolucent area between the roots in the furcation region. This reflects bone loss in the interradicular area of a multi-rooted tooth, which is the hallmark of periodontal destruction extending into the furcation. The appearance is often described as a radiolucency between the roots, sometimes triangular or wedge-shaped depending on the angle of the image.

Describing a conical tooth on an X-ray would relate to tooth/root shape rather than bone loss between roots, so it doesn’t depict furcation involvement. A widened lamina dura isn’t the typical feature here, and a normal radiograph would show no furcation changes at all.