Dental Assistant Practice Exam

What is the primary purpose of a periapical (PA) radiograph?

1. To examine bone structure

2. To record interproximal areas

3. To visualize crowns and roots!

4. To assess periodontal disease

The correct answer is: To visualize crowns and roots!

The primary purpose of a periapical (PA) radiograph is to visualize crowns and roots. Periapical radiographs are specifically designed to capture the entire tooth from the crown down to the root and the surrounding bone structure. This gives dentists crucial information about the tooth's health, including any possible infections or pathologies at the root level, such as abscesses or resorption. While assessing bone structure can be a secondary benefit of a PA radiograph, it is not its primary purpose. Additionally, recording interproximal areas is more related to bitewing radiographs, which are designed to show the upper and lower teeth in the same film to highlight the interproximal areas for caries detection. Lastly, though periodontal disease assessment can be achieved with periapical radiographs, they are not expressly designed for that purpose; other types, such as vertical bitewings, may provide better insights into the periodontal condition of the tissues surrounding the teeth. Thus, the correct focus of a PA radiograph centers on the visualization of crowns and their roots.