The zygomatic bone is also referred to as malar bone because it forms the visibility of the cheek that is termed mala in Latin.
Parts
The zygomatic bone is composed of the following 3 parts:
- A body
- 2 processes: frontal and temporal.
Body
It presents 3 surfaces, viz. orbital surface, lateral surface and temporal surface.
- A part of the lateral wall and floor of the Orbital surface. It’s a foramen, the zygomatico-orbital foramen, which carries a zygomatic nerve.
- Lateral surface is subcutaneous and presents a zygomaticofacial foramen via which zygomatico-facial nerve comes out.
- Temporal surface creates the part of anterior wall of the temporal fossa and presents a zygomaticotemporal foramen, which carries the zygomaticotemporal nerve.
Processes
All these are as follows:
- Frontal process: It’s a thick upward projection. It articulates with the zygomatic process of the frontal bone.
Its orbital surface presents a small tubercle near the orbital margin and 1 cm below the frontozygomatic suture named Whitnall’s tubercle. - Temporal process: It goes backwards and joins the zygomatic process of the temporal bone to create the zygomatic arch.
Clinical Significance
The powerful frontal process functions as a line of buttress for dispersion of force of impact to the frontal bone during mastication by the molar and premolar teeth.
The zygomatic bone ossifies in membrane. Occasionally a fissure divides the bone into upper and lower parts. This is a common attribute in the Mongolian race- making their malar prominences flat, for this reason it’s called OS Japonicum.
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