What does radiopaque refer to in a processed radiograph?

Radiopaque refers to the property of a material that does not allow X-rays or other forms of radiation to pass through it. In a processed radiograph, radiopaque structures appear white. This occurs because these materials, such as bone or certain dental restorations, absorb a significant amount of radiation, resulting in less exposure on the film or sensor. Consequently, areas that are radiopaque block the passage of X-rays, producing a white or light area on the final radiograph image.

In contrast, radiolucent materials, which allow radiation to pass through more easily, would appear dark or black on a radiograph. Understanding these distinctions is essential for interpreting dental radiographs accurately, as it enables practitioners to identify different types of tissues and materials based on their radiopacity.