National Dental Assisting Examining Board (NDAEB) Practice Exam

What is indicated when a radiograph shows that a radiolucent area at the apex is filling in?

1. Pulpal necrosis

2. Healthy tissue regeneration

3. Presence of a cyst

4. Ongoing infection

The correct answer is: Healthy tissue regeneration

When a radiograph shows that a radiolucent area at the apex of a tooth is filling in, it suggests healthy tissue regeneration. This finding indicates that the body is healing and the healing process is underway, often following prior pathology such as a periapical lesion or infection. The presence of new bone growth or dense, radiopaque areas in the radiolucent space signifies that the inflammatory process is resolving and the tissues are regenerating, leading to a positive prognosis for the tooth. In contrast to this, the other options reflect conditions that do not suggest healing. Pulpal necrosis indicates that the pulp tissue is dead and would not be associated with filling in of a radiolucent area. The presence of a cyst would typically remain as a radiolucency rather than filling in, indicating a stable lesion rather than regeneration. Ongoing infection would likely show an increasing radiolucent area or a lack of improvement, not a filling in of the area, which would represent deterioration rather than healing. Thus, the indication of healthy tissue regeneration aligns with the observation of a radiolucent area at the apex filling in.