What is the neurocranium used for?
The neurocranium has 8 bones. These bony elements form the so-called cranial vault, in which the brain and some sense organs reside, and the so-called base of the skull, which serves as a support for the aforementioned cranial vault. Some neurocranium bones are even, others are uneven.
Sutures are the points of contact between the various bones that make up a person's skull. ... The sutures therefore have the function of cushioning, which is ensured by the micromobility, also called elasticity, of the cranial sutures.
The facial massif, or splanchnocranium or viscerocranium, is a bone group that is part of the skull: where the neurocranium, with an exoskeletal function, is configured as a bone group with a protective function of the brain, the facial massif has a purely endoskeletal function, configuring itself as architecture. .
Flat bones - such as the shoulder blades, the breastbone and the bones of the skull and pelvis - are formed by a thin layer of spongy bone tissue inside which the bone marrow is located: this spongy layer is therefore enveloped by two laminae ( one on each side) of compact or cortical bone tissue.
Normally the cranial sutures close (ie they form the synostoses) only in the postnatal period; the metopic suture (suture of the anterior part of the skull) closes around the age of two, while the other sutures (sagittal, coronal and lambdoid) close around the age of 20.
Their too early closure can therefore lead to a premature welding of the bones of the skull which could therefore lead to more serious consequences due to the lack of sufficient space for the brain to grow in a space that becomes too small to contain it.
Intended to ossify between the 18nd and 6th month of life, there are XNUMX fontanelles in all: the fontanelles of the cranial vault, known as the posterior fontanelle and anterior fontanelle, and the two pairs of fontanelles of the base of the skull, whose name is fontanelle sphenoid (or antero-lateral fontanelles) and fontanelles ...
It consists of bones jointed together by sutures, with the exception of the mandible, the only mobile bone in relation to its masticatory function, it is composed, in addition to this, of six even bones (maxillary, zygomatic, lacrimal, lower cornet, nasal bone and bone palatine) and an unequal bone, the vomer.
long bones, which develop in length such as radius, ulna, humerus, tibia and fibula. flat bones, with a length and width greater than thickness, such as shoulder blades, breastbone and the bones of the skull. short bones that develop of similar length, width and thickness, such as the tarsus and carpus.
In a normal man of average height, the head represents one eighth of the total height. Its length is about 20cm, the width is about 18cm and the circumference is 50-60cm.
- the initial parts of the digestive and respiratory tracts. In humans, the splanchnocranium is made up of 14 bones.
- of the face: • Maxilla (two)
- •Jaw. • Nasal bone (two)
- • Lacrimal bone (two) • Zygomatic bone (two)
- • Palatine bone (two) • Lower cornet (two)
- • Vomere. •(joid bone)
The muscles of chewing are abductor (open the jaw) and adductor (close the jaw). The temporal, masseter, and medial pterygoid muscles are adductor, while the lateral pterygoid muscles are the major abductors of the jaw.
The facial massif is a bone group that is part of the skull and is composed of the zygomatic bones, the two maxillary bones, the palatine bones and the mandible. CT allows to evaluate these bone structures and the paranasal sinuses (frontal, maxillary, ethmoid and sphenoid).
These joints are immobile (syndesmosis), which is why they are called sutures, as they do not produce any type of movement, but it is as if the bones were fused together. This high congruence is given by the presence of dense fibrous connective tissue which increases their stability.
The sutures of the skull are fixed joints of the symfibrosis type present between the bones of the skull and characterized by dense fibrillar connective tissue.
Type of motionless joint or synarthrosis (such as synostosis, synchondrosis and symphysis) in which the joint surfaces are in a relationship of continuity through the interposition of a layer of dense connective tissue, directly dependent on the periosteum.
The short bones, such as the vertebrae, the bones of the foot (tarsus), the bones of the hand (carpus), act as a "bridge" and develop almost equally in length and width.
Short bones are characterized by similarly developing all three dimensions (resembling the shape of a cube), poor mobility and the presence of numerous joint facets. Within the human skeleton are therefore such the bones that make up the carpus and those that make up the tarsus.
According to the classification of bones based on shape, bones can be divided into: Long bones. Short bones. Flat bones.
The hyoid bone, or simpler hyoid, is the uneven and median, horseshoe-shaped bone that resides in the neck, at the base of the tongue, exactly between the chin and the thyroid cartilage of the larynx. The hyoid bone is an element of the human skeleton that is distinguished by its remarkable mobility.
The zygomatic bone (also called malar bone) is a bone of the splanchnocranium, even and symmetrical. It is placed in the superolateral part of the face, forming the prominence of the cheek, in relation above the frontal, medially with the maxilla, posteriorly with the temporal and with the sphenoid.
The palatine bone is an even and symmetrical bone of the splanchnocranium, present in many species of the animal kingdom. In humans, it is located in the posterior part of the nasal cavity, between the maxilla and the pterygoid process of the sphenoid.
The head circumference, at birth about 35 cm, grows in the first month is 2 or 3 cm, then about 1 cm per month.
In some cases, the too early closure of the anterior fontanel can compromise the normal growth of the skull causing a pathology that takes the name of craniostenosis, for which surgery is generally necessary.
3) immaturity of the cardia: the cardia is the valve that is located between the esophagus and the stomach and should prevent the ascent of gastric material into the esophagus. This valve matures during the first months of life and is increasingly effective in carrying out its function.