Some Arctic groups show a prominence of the zygomatic bone to adapt to extreme cold conditions while groups from Australia, Malaysia, and Oceania show some prominence of the zygomatic bone. However, there was diffusion of this trait in populations across the Behring Sea and the Arctic, North America, and South America areas. According to Oettle et al., prominence of the zygomatic bone was associated with Eastern Asian populations and populations from Eastern Europe. The zygomatic bone could also vary among different ethnic populations. According to a study that examined 102 dry hemicrania, the zygomaticoforamen ranged from being absent to have as many as four small openings, and half of the specimens had one foramen. The zygomaticofacial foramen, located at the mid-lateral surface of the zygomatic bone that gives off the zygomaticofacial nerve and zygomaticofacial vessels, has also been found to vary from being double or being absent. For the most part, there is an extra suture that runs perpendicularly from the facial portion of the maxillozygomatic suture and dorsolaterally to the zygomatic bone, which imparts it a bipartite morphology. Īs mentioned previously, usually, the zygomatic bone is a single bone bounded by sutures, but it can be divided by extra sutures into two or more parts. The zygomaticofacial branch traverses through the lateral wall of the orbit and goes through the zygomaticofacial foramen. It also joins with the zygomatic branches of the facial nerve and inferior palpebral branches of the maxillary nerve. The zygomaticotemporal branch runs along the inferolateral walls of the orbit, travels through the zygomaticofacial foramen of the zygomatic bone, and innervates the orbicularis oculi to reach the skin of the malar area. The zygomatic nerve, which originates from the maxillary division of the trigeminal nerve, gives off the zygomaticotemporal and zygomaticofacial branches. Finally, the cervical branch provides sensation to the muscles below the chin and the platysma muscle. The buccal branch provides sensation to the zygomatic and buccinator muscles while the mandibular branch innervates the lower region of the face. The temporal branch innervates the frontalis and orbicularis oris while the zygomatic branch innervates the middle region of the face. The extratemporal region of the facial nerve has five terminal branches: the temporal, zygomatic, buccal, mandibular, and cervical branches. It then traverses through the temporal bone and the stylomastoid foramen where it branches off at the parotid gland. It originates from the brain stem and travels posteriorly to the abducens nerve and anteriorly to the vestibulocochlear nerve. The facial nerve (cranial nerve VII) is primarily responsible for innervating the muscles of the face. It forms from the temporal process of the zygomatic bone and the zygomatic process of the temporal bone. The zygomatic arch is also vital in the mastication system, as it gives rise to the masseter muscle, which is the major jaw adductor in mammals. It also plays a crucial role in maintaining the aesthetic beauty and function of the face and protecting the eyes. The zygomatic bone can withstand the forces of mastication and transmitting reactionary forces from the maxilla. ![]() For the most part, there is an extra suture that runs perpendicularly from the facial part of the maxillozygomatic suture and dorsolaterally to the zygomatic bone, which imparts it a bipartite morphology. Usually, the zygomatic bone is a single bone bounded by sutures that articulate with the frontal, maxilla, temporal, and sphenoid bones, but it can be divided by extra sutures into two or more parts. The zygomatic bones are a pair of diamond-shaped, irregularly-shaped bones that protrude laterally and form the prominence of the cheeks, a portion of the lateral wall, the orbit floor, and some portions of the temporal fossa and infratemporal fossa.
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