American Board of Orthodontics (ABO) Practice Exam

The vertical bitewing radiograph is considered the best type among the given options for periodontal assessment due to its ability to display the height of the alveolar bone and the presence of periodontal disease more effectively than the other imaging techniques.

Vertical bitewings capture a more detailed view of the interproximal areas of the molars and premolars, where periodontal issues such as bone loss can be most prevalent. The orientation of the film allows for better visualization of the bone levels relative to the teeth, facilitating a more accurate assessment of periodontal health. This type of radiograph is particularly useful for evaluating changes in bone height over time, which is crucial for monitoring periodontal disease progression.

In contrast, the horizontal bitewing primarily shows caries detection and may not provide sufficient information about the periodontal condition. Panoramic views, while useful for a broader overview of oral structures, lack the resolution needed for specific periodontal measurements, making them less effective for focused assessments. CT scans, while providing detailed three-dimensional images, are generally not used as a first-line tool in periodontal assessment due to higher radiation exposure and cost, along with their complexity in interpretation for this specific purpose.