How far below the margin of the preparation should the provisional crown sit?

The correct answer is that the provisional crown should sit flush with the margin of the preparation. This is important for several reasons. When the provisional crown sits flush, it ensures that there is no gap between the crown and the tooth preparation, which helps maintain the integrity of the dental work and prevents the accumulation of plaque and bacteria that could lead to decay or periodontal issues.

Ensuring a precise fit is also essential for the proper occlusion and overall function of the dental restoration. A well-fitted provisional protects the underlying tooth structure and supports the gingival tissues, helping to maintain the position of the gums during the temporary phase before the final restoration is placed.

If the provisional crown were to sit below the preparation margin, it might lead to discomfort, improper occlusion, or a compromised seal, while sitting above could leave the preparation exposed, increasing the risk of sensitivity or decay. Therefore, positioning the provisional crown flush is a critical aspect of effective dental assisting and restorative dentistry.