Skull of the newborn
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
The skull of a newborn has a number of significant features. Brain skull as a result of active brain growth and early formation of the sense organs by volume is 8 times larger than the facial. In an adult human, due to the full development of the masticatory apparatus, the brain skull is only 2 times larger than the facial skull. The newborn eye sockets are wide. The base of the skull, compared with the vault, lags behind in growth, the bones are connected to each other by means of wide cartilaginous and connective tissue layers. The bumps of the frontal and parietal bones are well pronounced, and therefore, when examining the skull from above, it appears quadrangular. The frontal bone consists of two halves, the superciliary arches are absent, the frontal sinus is not yet present. Jaws are underdeveloped, which determines the low height of the facial skull. The lower jaw consists of two parts (two halves). The parts of the temporal bone are separated from each other by well-expressed connective tissue or cartilaginous layers, the mastoid process is not developed. On the bones of the skull the muscular knolls and lines are not pronounced.
The most characteristic sign of the newborn's skull is fontanel (fonticuli). They are neocostenive-connective tissue (webbed) areas of the cranial vault. There are six fontanelles in total: two lie along the median line of the cranial vault and 4 fontanels of the lateral
- The largest is the frontal fontanel (fonticulus anterior). It is rhomboid, located between the two parts of the frontal bone and both parietal bones, overgrown in the 2nd year of life.
- The posterior (occipital) fontanel (fonticulus posterior) has a triangular shape. It is located between two parietal bones in front and occipital scales behind; grows up on the 2nd month of life.
- Lateral fontanels are paired, two on each side.
- The anterior wedge-shaped fontanel (fonticulus sphenoidalis) is located at the junction of the large wing of the sphenoid bone with the frontal, parietal bones and the temporal bone scales; It grows up on the 2nd-3rd month of life.
- Posterior - mastoid fontanel (fonticulus mastoideus) - formed by temporal, parietal bones and occipital scales; It grows up on the 2nd-3rd month of life.
Sutures between the bones of the cranial vault are not formed, the edges of the bones are even. Only at the 3rd year of the child's life does the development of the teeth begin at the skull bones, which gradually increase and enter the gaps between the teeth of the adjacent bone. This is how jagged seams are formed. From the description of the newborn's skull it is evident that by the time of birth its development is far from over. It continues in subsequent years of life.
[