Where does the central ray (CR) enter for a lateral projection of the facial bones?

In a lateral projection of the facial bones, the central ray (CR) enters midway between the outer canthus and the external auditory meatus. This specific positioning is crucial as it ensures that the facial structures are properly visualized without overlapping from other anatomical parts. This midpoint provides a balanced view of the facial bones, allowing for accurate assessment of their dimensions and relationships.

The choice of this entry point is significant because it aligns the radiographic beam in a way that minimizes distortion and maximizes clarity in the imaging of the various facial bones. Factors such as the anatomy of the skull and the orientation of the facial structures dictate this specific entry point. Thus, utilizing the midpoint between the outer canthus and the external auditory meatus ensures optimal results when evaluating the lateral aspect of the facial bones.