Chapter: Neurocranium

Fontaneles

The desmocranium and the skull of a newborn before ossification is soft during palpation and contains non- ossified spots of the connective tissue called cranial fontanels (fonticuli cranii). They are situated at the junctions of the skull’s sutures. The following fontanels are distinguished: Anterior fontanele (fonticulus anterior) exists in the midline between the coronal and the sagittal suture (anterior …

Fontaneles Read More »

Temporal bone

The temporal bone (os temporale) is a paired bone forming the lateral part of the base of the skull and it contains the organs of hearing and equilibrium. It has three parts (squamous part, petrous part, and tympanic part).

Ethmoid bone

The ethmoid bone (os ethmoidale) is an unpaired bone of the neurocranium, although most of it makes up the viscerocranium. The ethmoid bone is located centrally between the bones of the visceral cranium and comes in contact with most of them to form the nasal and orbital cavities. The bony plates of the ethmoid bone are arranged in the form of the …

Ethmoid bone Read More »

Sphenoid bone

The sphenoid bone (os sphenoidale)is an unpaired bone resembles a bat or a flying insect, which explains the naming of its parts (pterygoid processes – pterygion = wing). The sphenoid bone has the following parts:

Occipital bone

The unpaired occipital bone (os occipitale) forms the posterior part f the base and posterior wall of the skull. It is made up of four parts, which fuse to form a single bone forming the borders of the foramen magnum as follows, the: Basilar part (pars basilaris) – anteriorly. Squamous part (squama occipitalis) – posteriorly. Lateral or condylar parts (partes laterales) –laterally.

Parietal bone

The parietal bone (os parietale)is a paired, flat bone which forms the roof of the skull. The parietal bone has two surfaces, four borders, and four angles. The parietal bone has four borders: The parietal bone has four angles:

Frontal bone

The frontal bone consists of three parts (squamous part, orbital part, and nasal part).

Base of the skull

The base of the skull is formed by eight bones including the superior part of the ethmoid bone anteriorly, the sphenoid bone centrally, the inferior portions of the frontal bone anteriorly, the occipital bone posteriorly and the temporal bones laterally.

Calvaria

The calvaria is the skull cap (cranial vault), consisting of a series of flat bones. It is formed by the parietal bones and squamous parts of the frontal and occipital bones. The bones of the neurocranium fuse together and form the following sutures: Sagittal suture (sutura sagittalis) which is located between two parietal bones in the median sagittal plane. …

Calvaria Read More »