National Dental Assisting Examining Board (NDAEB) Practice Exam

What must an impression tray with a smooth surface be treated with before use?

1. Disinfectant solution

2. Water

3. Painting with an adhesive substance

4. Vaseline

The correct answer is: Painting with an adhesive substance

An impression tray with a smooth surface should be treated with an adhesive substance before use. This step is crucial because the adhesive helps ensure that the impression material adequately adheres to the tray during the impression-taking process. A secure bond between the impression material and the tray is essential for capturing accurate dental impressions, as it prevents the material from separating or tearing when being removed from the patient's mouth. While other treatments, such as disinfection, water, or Vaseline, may have their own uses in dental procedures, they do not serve the same purpose as applying an adhesive. Disinfecting a tray is important for infection control, but does not enhance the retention of the impression material. Water may be used to moisten certain materials or clean the tray, but it does not provide the necessary adhesion. Vaseline, being a lubricant, could actually prevent the impression material from gripping the tray effectively, thereby compromising the quality of the impression taken. Therefore, treating the tray with an adhesive is the most effective method to ensure optimal results in capturing the details needed for dental work.