Periapical film is primarily used to examine the region around which part of the tooth?

Periapical film is specifically designed to capture detailed images of the entire tooth, including both the crown and the root, as well as the surrounding supporting structures. However, its primary focus is on the area around the apex of the root. This region is critical for identifying issues such as periapical abscesses, root fractures, and other pathologies that can affect the root and the underlying bone.

By capturing the area near the apex, radiologists and dentists can assess the health of the tooth root, surrounding bone, and any pathological changes that may indicate the presence of infection or other dental concerns. This is essential for formulating appropriate treatment plans.

Other options, while relevant to dental anatomy, do not specifically emphasize the periapical aspect that the periapical film targets. The crown is concentrated at the top of the tooth, while enamel constitutes the outer layer and does not reflect root pathology. The periodontal ligament is indeed important for tooth support, but periapical films focus predominantly on the area surrounding the apices of the roots. Hence, the correct choice highlights the primary function of periapical films in dental radiology.