Dental Assistant Practice Exam

Which term describes an area that appears lighter on a radiographic image?

1. Radiolucent

2. Radiopaque

3. Translucent

4. Opaque

The correct answer is: Radiopaque

The term that describes an area that appears lighter on a radiographic image is "radiopaque." Radiopaque materials absorb more radiation, appearing white or lighter on a radiograph, indicating that they are denser. Common examples of radiopaque materials include metal restorations, bone, and teeth, which absorb X-rays and do not allow them to pass through to the film, resulting in a lighter image. In contrast, the other terms have different meanings: "radiolucent" refers to areas that appear darker on a radiograph due to the ability of X-rays to pass through them, indicating less density, such as soft tissues or cavities. "Translucent" describes materials that allow some light through but not a clear image, which is less relevant in the context of radiographs. "Opaque" generally refers to materials that do not allow light or radiation to penetrate at all, often used in broader contexts outside of radiographic imaging.