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## **Cranial Sutures** - **Coronal:** extends laterally across the superior surface of the skull along a coronal plane. Articulates between the frontal bone and the parietal bones. - **Lambdoid:** extends like an arc across the posterior surface of the skull. Articulates between the parietal bones...

## **Cranial Sutures** - **Coronal:** extends laterally across the superior surface of the skull along a coronal plane. Articulates between the frontal bone and the parietal bones. - **Lambdoid:** extends like an arc across the posterior surface of the skull. Articulates between the parietal bones and the occipital bone. - **Sagittal:** extends between the coronal and lambdoid sutures along the midsagittal plane. Articulates between the right and left parietal bones. - **Squamous:** on each side of the skull, articulates between the temporal bone and the parietal bone. **Variations** - The timing of suture closure can be highly variable. - The coronal suture usually fuses first, then the sagittal suture, then the lambdoid suture, and lastly the squamous suture. - **Sutural Bones (Wormian Bones):** can be found in some individuals, ranging in size from a tiny pebble to a quarter. They represent independent bone ossification centers. ## **Orbital and Nasal Complexes** **Orbital Complex** - The orbital complex consists of seven bones: sphenoid, frontal, zygomatic, maxilla, palatine, ethmoid, and lacrimal. - The orbital complex encloses and protects the eyes and the muscles that move them. **Nasal Complex** - Composed of bones and cartilage that encloses the nasal cavity and the paranasal sinuses. - Most of these bones are best seen in sagittal section. **Image Caption** - Left Orbit: Illustration of the bones that comprise the orbit of the eye. **Key Points** - The image shows the left orbit. - Seven bones are named and labeled: - Frontal - Lacrimal - Ethmoid - Maxilla - Palatine - Sphenoid - Zygomatic - The key features of the orbit are labeled: - Optic canal - Superior orbital fissure - Inferior orbital fissure - Floor of orbit - Orbital surface of maxilla - Medial wall - Lateral wall - Several bones from other areas that are not part of the orbit are shown: - Greater wing of sphenoid bone - Zygomatic process of frontal bone