Dental Admissions Test (DAT) Practice Test

Which dental x-ray is most commonly used to detect cavities between teeth?

1. Panoramic x-ray

2. Bitewing x-ray

3. Cephalometric x-ray

4. Periapical x-ray

The correct answer is: Bitewing x-ray

The bitewing x-ray is most commonly used to detect cavities between teeth because it provides a clear view of the upper and lower teeth in a specific area of the mouth, particularly the premolars and molars. This type of x-ray captures the occlusal surfaces and the interproximal areas where cavities frequently develop but might not be visible during a standard visual examination. Bitewing x-rays are specifically designed to show any carious lesions that may exist between adjacent teeth, which is critical since these areas are often hard to access and inspect visually. Additionally, they also allow for the assessment of bone levels, aiding in the overall evaluation of oral health. In contrast, panoramic x-rays provide a broad overview of the entire mouth and jaws, making them less effective for pinpointing specific issues like interproximal decay. Cephalometric x-rays are primarily used in orthodontics and provide a lateral view of the head to evaluate dental and skeletal relationships, rather than focusing on cavities. Periapical x-rays capture the entire tooth, including the root and surrounding bone, but do not emphasize the spaces between the teeth as bitewing x-rays do. Thus, the bitewing x-ray is the most effective choice for detecting interproximal cavities.