Which projection best demonstrates the zygomatic arch?

The SMV (submentovertex) projection is the best choice for demonstrating the zygomatic arch because it provides a clear view by placing the zygomatic arch perpendicular to the imaging receptor. This projection requires the patient's head to be tilted back so that the x-ray beam is directed under the chin and exits at the crown of the head, allowing for an unobstructed view of the zygomatic arches.

In this position, the zygomatic arch can be seen laterally without superimposition from other cranial structures, which is essential for proper assessment. This detail is particularly important in dental and maxillofacial imaging where the zygomatic arch needs to be accurately evaluated for fractures or other pathologies.

Other projections, while useful for various anatomical demonstrations, do not provide the same clarity or isolation of the zygomatic arch that the SMV projection does.