Age features of the skull. Skull of the baby. Stitches of the skull: anatomy

The determining role in the formation and subsequentthe development of the skull belongs to the brain, teeth, chewing muscles and sensory organs. In the process of growth, the head undergoes significant changes. In the course of development, age, sex and individual features of the skull. Let's consider some of them.

Newborns

Skull of the baby has a specific structure. The space between the bone elements is filled with connective tissue. Newborns are completely absent seams of the skull. Anatomy This part of the body is of special interest. At the joints of several bones there are 6 fontanelles. They are covered with connective tissue plates. There are two unpaired (posterior and anterior) and two paired (mastoid, wedge-shaped) fontanel. The largest is considered frontal. It has a rhomboid shape. It is located at the point of convergence of the left and right frontal and both parietal bones. Due to fontanelles baby skull very elastic. When the head of the fetus passes through the birth canal, the roof edges overlap each other tile. Due to this, it decreases. By two years, as a rule, seams of the skull. Anatomy previously studied quite original. Medics of the Middle Ages applied hot iron to the fontanel area with diseases of the eyes and brain. After scar formation, doctors caused suppuration with various irritating agents. So they believed that opening the way for accumulating harmful substances. In the configuration of the seams, doctors tried to see the symbols and letters. The doctors believed that they contained information about the fate of the patient.

Features of the structure of the skull

This part of the body of the newborn is differentsmall size of facial bones. Another specific feature is the fontanels mentioned above. In the skull of the newborn there are traces of all 3 unfinished stages of ossification. Rodnichki are remnants of the membranous period. Their availability is of practical importance. They allow the bones of the roof to shift. The anterior fontanel is located on the median line on the joint of 4 joints: 2 halves of the coronary, frontal and sagittal. It grows up in the second year of life. The back fontanelle has a triangular shape. It is located between the two parietal bones in front and the scales of the occiput bone behind. It heals in the second month. In the lateral fontanels, wedge-shaped and mastoid are distinguished. The first is located on the segment of convergence of the parietal, frontal, scales of the temporal and large wing of the sphenoid bones. It grows up in the second or third month. The mosaic fontanel is located between the parietal bone, the base of the pyramid in the temporal and scales of the occipital.

Cartilage stage

At this stage, the following agefeatures of the skull. Between the separate, not merged elements of the foundation bones are found cartilaginous layers. Airborne sinuses are not yet developed. Because of the weakness of the musculature, different muscular ridges, knolls and lines are weakly expressed. For the same reason, coupled, in addition, with a lack of chewing function, jaws are underdeveloped. There are almost no alveolar processes. The lower jaw is composed of 2 uncombined halves. Because of this, the face does not move forward relatively to the skull. It is only 1/8 part. In this case, the ratio of the face to the skull in the adult is 1/4.

Offset of bones

Age features of the skull after birthmanifested in the active expansion of cavities - nasal, cerebral, oral and nasopharyngeal. This leads to a displacement of the bones surrounding them, in the direction of the growth vectors. The movement is accompanied by an increase in the length and thickness. With the marginal and superficial growth, the curvature of the bones begins to change.

Postnatal period

At this stage age features of the skull manifest in the uneven growth of facial andbrain departments. The linear dimensions of the latter increase by 0.5, and the first dimensions by a factor of three. The volume of the brain department in the first six months is doubled, and by the 2-year - it is tripling. From the age of 7, growth slows down, in the pubertal period it accelerates again. By 16-18 years the development of the arch ceases. The base increases in length to 18-20 years and ends when the wedge-occipital synchondrosis is closed. The growth of the facial division is more prolonged and uniform. Most actively grow bones near the mouth. Age features of the skull in the process of growth are manifested in the coalescence of partsbones, separated in newborns, differentiation in structure, pneumatization. The relief of the inner and outer surfaces becomes more defined. At an early age on the seams formed smooth edges, by the age of 20 jagged joints are formed.

Final stages

By the age of forty obliteration of sutures begins. It covers all or most of the connections. In advanced and old age, osteoporosis of cranial bones is noted. Thinning of the plates of a compact substance begins. In some cases, a thickening of the bones is observed. Atrophy in the alveolar processes of the jaw becomes more pronounced in the facial area due to loss of teeth. This causes an increase in the angle of the lower jaw. As a result, the chin goes forward.

Gender characteristics

There are several criteria by whichdifferent male skull from female. Such signs include the degree of severity of roughness and tuberosity in the areas of muscle attachment, development of mastoid processes and occipital external tuber, performance of the upper jaw, etc. The male skull is more developed in comparison with the female one. Its outlines are more angular due to the severity of roughness and tuberosity in the areas of attachment of chewing, temporal, occipital and cervical muscles. Frontal and parietal tubercles are more developed in women, in men - nadperenosie and superciliary arches. in the latter, the lower jaw is heavier and larger. In the region of the lower margin and the corners of the inner part of the chin, tuberosity is distinctly expressed. This is due to the attachment of bile, chewing and pterygoid muscles. Depending on gender, the shape of the human skull also varies. Men have a beveled forehead, which goes into a rounded crown. Often there is an elevation in the direction of the arrow-shaped seam. The forehead of women is more vertical. It goes into a flat crown. In men, the orbit is lower. As a rule, they have a rectangular shape. Their upper edge is thickened. In women, the orbits are located higher. They are approximated to an oval or round shape with upper, sharper and thin edges. On the female skull, the alveolar process in the upper jaw often protrudes. Nosolobny angle in men is expressed in most cases clearly. On the female skull, the frontal bone to the nasal passes more smoothly.

Additionally

The shape of the human skull does not affectmental capacity. Based on the results of numerous studies of anthropologists, it can be concluded that there is no reason to believe that a race predominates in the size of the brain department. In Bushmen, Pygmies and some other tribes, the size of the head is somewhat smaller than that of other people. This is due to their small growth. Often, a decrease in the size of the head can be the result of poor nutrition over the centuries and the influence of other unfavorable factors.