How you get the total number of bones in the average human skull all depends on how you count them, and the age-range of the skull you are examining. For instance, the human skull is made up of 45 separate bone structures at birth. As a child grows, bones gradually fuse together, interlocking at the sutures at about the age of two. This is referred to as Ossification (or osteogenesis). By adulthood, most humans have a total of 29 distinct bones that make up the skull region.
Many argue that the true number is 28 bones since they do not include the hyoid bone in their total count. But, when you properly define what makes up the human skull region, one can reasonably conclude that the hyoid bone is a crucial part of the skull because it serves a distinct role in how the skull functions. The hyoid provides attachment to the muscles of the floor of the mouth and the tongue above.
List of Skull Bones Shown in the Illustration
|Frontal (1) - The frontal bone is a single bone located at the front of the skull. It is what makes up the forehead, upper eye orbit, and portions of the nasal cavity. The bone extends upward where it meets the two parietal bones at the coronal suture. This suture extends from the roof of the cranium to the temple area.||
|Parietal (2) - This pair of bones is divided by the sagittal suture at the very top of the skull. The parietal bones form the majority of the suface area of the skull to include most of the top region and sides of the skull.|
|Occipital (1) - The occipital bone is a single bone found at the lower back area of the cranium.|
|Temporal (2) - The temporal pair forms the lower portion and sides (temple region) of the cranial structure.|
|Sphenoid (1) - As the illustration partially shows, the single sphenoid bone extends from the temples of the skull and includes a portion of the orbital regions.|
|Zygomatic (2) - The zygomatic pair define the cheek area and extend to form portions of the orbit, temporal and infratemporal fossa.|
|Mandible (1) - The "U" shaped mandible is a single bone that forms the lower jaw.|
|Maxilla (2) - The pair of bones of the upper jaw and form the roof of the mouth (palate).|
|Inferior nasal conchae (2), Vomer (1) - Nasal cavity.|
|Nasal (2) - The nasal pair join to form the bridge of the nose.|
|Lacrimal (2) - The lacrimal pair of bones are located inside the orbits of the eyes, situated between the maxilla and ethmoid.|
|Ethmoid (1) - The ethmoid is a single bone located at the roof of the nose, between the two eye orbits.|
List of Bones Not Shown in the Illustration
|NS||Palatine bones (2) - This pair of bones makeup part of the nasal cavity roof of the mouth (hard palate).|
|NS||Ossicles (auditory ossicles) middle ear
malleus (2), incus (2), stapes (2), aka. hammer, anvil and stirrup.
|NS||Hyoid bone (1) (lingual bone)|