National Dental Assisting Examining Board (NDAEB) Practice Exam

What is the primary function of a custom tray in dental impressions?

1. To create a model

2. To secure a final impression

3. To hold the impression material

4. To ensure patient comfort

The correct answer is: To secure a final impression

The primary function of a custom tray in dental impressions is to secure a final impression. Custom trays are specifically designed to fit the unique contours of a patient’s mouth, which allows the impression material to be adequately contained when applied. This secure fit ensures that the impression material will remain in place, capturing the necessary details of the dental anatomy and providing more accurate results compared to stock trays. While custom trays can promote patient comfort by being tailored to their mouth, the main purpose is to ensure stability and accuracy during the impression process, which is vital for creating dental models, prosthetics, or orthodontic appliances. It’s important to note that while custom trays do hold the impression material, their primary function extends to maintaining the integrity and accuracy of the impression itself for prosthodontic or orthodontic procedures.