A 32-year-old female has a crown on the upper central that keeps falling off. The patient has a deep bite. What is the cause?

Correct answer: A. Problem with occlusion (deep bite creates dislodging forces)

• A. Correct. A deep vertical overbite creates excessive occlusal forces on the crown that overcome cement retention. The crown experiences shear and tensile forces each time the mandible closes, repeatedly dislodging it.
• B. Incorrect. While overtaper reduces retention, the clinical history specifying 'deep bite' points to occlusion as the primary cause.
• C. Incorrect. Insufficient cement is possible but the deep bite is the contextual clinically specific cause.
• D. Incorrect. Poor margins cause microleakage and secondary caries, not repeated dislodgement.