Question

Cusp capping is considered when the extension of the cavity preparation reaches which of the following?

• A. More than half of the primary groove to the central groove
• B. More than two-thirds or half of the primary groove to the central groove
• C. More than half of the secondary groove to the central groove
• D. Extension is limited to the marginal ridge only

Hint:

If a cavity undermines more than half to two-thirds of a cusp, consider cusp capping to prevent fracture.

Answer 1

The Correct Option is B

Step 1: Concept of Cusp Capping.
Cusp capping is a restorative procedure in which weakened cusps are reduced and covered with restorative material to prevent fractureIt is commonly indicated in large posterior restorations where significant tooth structure has been removed
Step 2: Indication Based on Cavity Extension.
When the cavity preparation extends significantly into the primary groove toward the central groove, the structural integrity of the cusp becomes compromisedIf the extension reaches more than half to two-thirds of the distance from the primary groove to the central groove, the cusp becomes weak and prone to fracture
Step 3: Evaluation of Options.
(A) More than half of the primary groove to the central groove: Partially correct but not as precise as option B
(B) More than two-thirds or half of the primary groove to the central groove: CorrectThis level of extension significantly weakens the cusp and indicates cusp coverage
(C) More than half of the secondary groove to the central groove: Secondary grooves do not determine cusp strength significantly
(D) Extension is limited to the marginal ridge only: This does not typically require cusp capping
Step 4: Conclusion.
Therefore, cusp capping is indicated when the cavity preparation extends more than half to two-thirds of the primary groove toward the central groove