What is the primary use of a panoramic X-ray?

A panoramic X-ray primarily serves to provide a comprehensive view of the entire mouth, including the teeth, jaws, and related structures in a single image. This type of imaging is particularly useful for detecting third molars, commonly known as wisdom teeth, which are frequently impacted or may require extraction. Additionally, panoramic X-rays can reveal cysts, tumors, and other abnormalities in the oral and maxillofacial region, aiding in diagnosis and treatment planning.

While the other options address important dental concerns, they do not capture the primary function of panoramic X-rays. For example, detecting cavities typically requires localized radiographs like bitewings, and assessing dental alignment is often performed through cephalometric X-rays or intraoral images. Determining tooth sensitivity, on the other hand, involves clinical examination rather than imaging techniques. Thus, option C accurately describes the primary and distinctive capability of panoramic X-rays in dental diagnostics.