Extraoral anatomy in CBCT – a literature review. Part 2: Zygomatico-orbital region.

This second article about extraoral anatomy as seen in cone beam computed tomography (CBCT) images presents a literature review of the zygomatico-orbital region. The latter bounds the maxillary sinus superiorly and laterally. Since pathologic changes of the maxillary sinus are a frequent indication for three-dimensional radiography, the contiguous orbital cavity and the zygomatic bone may become visible on CBCT scans. The zygomatic bone forms the cheek prominence and has large contact areas with the maxilla through the zygomaticomaxillary suture in the infraorbital region as well as with the sphenoid bone along the lateral orbital wall. Each of the three surfaces of the zygomatic bone displays foramina that transmit neurovascular structures. The orbital cavity is located immediately above the maxillary sinus from which it is separated only by a thin bony plate simultaneously serving as the orbital floor and the roof of the maxillary sinus. Several openings, such as the superior and inferior orbital fissures, the ethmoidal and cranio-orbital foramina, and the optic and infraorbital canals, connect the orbit to the anterior and middle cranial fossae as well as to the infratemporal and pterygopalatine fossae.