Class II furcation involvement is defined as what?

Class II furcation involvement is defined as what?

• A. Horizontal attachment loss less than 3 mm into furcation
• B. Horizontal attachment loss greater than 3 mm but not through entire furcation
• C. Through-and-through destruction
• D. No furcation involvement

Answer: (B)

The main idea is how furcation involvement is classified by how far the horizontal bone loss reaches into the furcation. In Class II, there is horizontal bone loss into the furcation that is more than 3 mm deep but does not extend through to the opposite side of the tooth. You can insert the probe into the furcation area, but it cannot pass completely through to the other side. This distinguishes it from Class I (less than that depth, a shallow entry) and Class III (through-and-through destruction), and from no furcation involvement.

The main idea is how furcation involvement is classified by how far the horizontal bone loss reaches into the furcation. In Class II, there is horizontal bone loss into the furcation that is more than 3 mm deep but does not extend through to the opposite side of the tooth. You can insert the probe into the furcation area, but it cannot pass completely through to the other side. This distinguishes it from Class I (less than that depth, a shallow entry) and Class III (through-and-through destruction), and from no furcation involvement.