The skull is made up of 22 different bones - 8 cranial bones that enclose your brain within the neurocranium, and 14 facial skeleton bones. There are also 6 ear bones. With the exception of the mandible, the bones of the skull are joined by sutures, which are a kind of joint that is synarthrodial - in other words, it can’t move.
The 8 cranial bones include one occipital bone, one sphenoid bone, one ethmoid bone, one frontal bone, a pair of parietal bones, and a pair of temporal bones. The occipital bone is found at the back of the skull. The sphenoid bone can be found in the middle inferior portion of the neurocranium and kind of looks like a butterfly. It is in front of the temporal bone and is one of 7 bones that articulate to form the orbit. The other six are the frontal bone, the lacrimal bone, the ethmoid bone, the zygomatic bone, the maxillary bone, and the palatine bone.
The ethmoid bone is found between your eyes, located at the roof of the nose, and separates the nasal cavity from the brain. The frontal bone is the bone of your forehead. It has two portions - one vertical, and also the horizontally-oriented orbital portion.
The remaining 4 bones are a pair of parietal bones and a pair of temporal bones. The parietal bones are joined together at the top of the skull. Together, they form the top and sides of the neurocranium. Each bone is roughly quadrilateral in shape. The temporal bones can be found at the sides and base of the skull. They are overlaid by what we call the temples. It is inside the petrous part of the temporal bone that we find the ossicles - the bones of the middle ear and the smallest bones in your body. A set of three ossicles is found on each side of your head, so there are 6 ossicles in total. These bones include the hammer, anvil, and stirrup, also called the malleus, incus, and stapes. The ear canal, which joins the outer and middle ears, is known as the external acoustic meatus. There is also the internal acoustic meatus, which is a tube running from the inner ear to the back of the skull - to what’s called the posterior cranial fossa. We will discuss the three fossa of the skull will be discussed in a later video.
So those were the 8 cranial bones. Again, these included the occipital bone, the sphenoid bone, the ethmoid bone, the frontal bone, a pair of parietal bones, and a pair of temporal bones.
Now for the facial bones. The facial bones include the mandible, the vomer, a pair of maxillae, a pair of palatine bones, a pair of nasal bones, a pair of nasal conchae, a pair of zygomatic bones, and a pair of lacrimal bones.
The mandible is your jawbone. It is the largest bone in the human face and is the only movable bone in the skull apart from the ossicles. The other unpaired facial bone is the vomer, which forms the inferior part of the nasal septum, and articulates with the sphenoid, ethmoid, palatine bones, and maxillary bones. A pair of maxillae are fused together at the intermaxillary suture to form the bone of the upper jaw. This includes the hard palate in the front of your mouth. The two palatine bones, together with the maxillae, comprise the hard palate. They are located at the back of the nasal cavity.
The pair of nasal bones form the bridge of the nose and are joined at the internasal suture. The nasal conchae are thin bony elements forming the upper chambers of the nasal cavities. They are composed of three pairs - the inferior, middle, and superior conchae. The zygomatic bones - or your cheekbones - articulate with the maxilla, temporal bone, sphenoid bone, and frontal bone. The lacrimal bone is a small bone in the front of the medial wall of the orbit.
3D Model from www.turbosquid.com/3d-models/...
26 июн 2024
