Which type of radiograph is most useful for assessing alveolar bone levels in periodontal disease involving the posterior teeth?

Vertical bitewing radiographs are superior to standard horizontal bitewings for evaluating alveolar bone loss in periodontal disease. Because vertical bitewings have the receptor oriented vertically (portrait orientation), they capture more of the root surface and alveolar bone height, including the apical one-third of root length. This allows detection of moderate to severe bone loss and visualization of furcation involvement that would be cut off on standard horizontal bitewings. Horizontal bitewings are excellent for caries detection and early crestal bone changes. Periapical radiographs show the entire root and periapical region but only one tooth at a time. Panoramic provides an overview but lacks the detail needed for periodontal assessment.