Dental OSCE (Objective Structured Clinical Examination) Practice Exam

What causes thermal sensitivity after cementing a crown?

1. Improper crown fit

2. Micro leakage

3. Excess cement

4. Temperature changes in the dental office

The correct answer is: Micro leakage

Thermal sensitivity after cementing a crown is primarily related to micro leakage. This phenomenon occurs when there are gaps between the crown margins and the prepared tooth structure, allowing oral fluids and temperature changes to penetrate. These gaps can lead to the thermal expansion and contraction of the tooth structure beneath the crown, resulting in discomfort or sensitivity when exposed to hot or cold stimuli. The presence of micro leakage not only compromises the seal of the crown but can also lead to the potential for bacterial infiltration, further exacerbating sensitivity or even leading to pulpitis. The other options, while they may contribute to complications following crown placement, do not accurately explain the specific mechanism behind thermal sensitivity caused by poor sealing at the margins. For instance, while improper crown fit can be a concern, it is the micro leakage that directly ties to temperature changes and the subsequent sensitivity experienced by the patient.