Calvaria (skull)
Encyclopedia
The calvaria is the upper part of the cranium and surrounds the cranial cavity containing the brain.

The calvaria (skull cap) is made up of the frontal, occipital and right and left parietals.

The outer surface of the skull possess a number of landmarks. The point at which the two parietal bones and frontal bones meet is known as "Bregma". The point at which the two parietal and occipital bone meet is known as "Lambda"
Not only do these landmarks indicate the fontanelle
Fontanelle
A fontanelle is an anatomical feature on an infant's skull.-Anatomy:Fontanelles are soft spots on a baby's head which, during birth, enable the bony plates of the skull to flex, allowing the child's head to pass through the birth canal. The ossification of the bones of the skull causes the...

 in newborns they also act as reference points in medicine and surgery

In the fetus, the formation of the Calvaria involves a process known as intramembranous ossification
Intramembranous ossification
Intramembranous ossification is one of the two essential processes during fetal development of the mammalian skeletal system by which bone tissue is created. Unlike endochondral ossification, which is the other process by which bone tissue is created, cartilage is not present during intramembranous...

, although the base of the skull (underlying the brain) develops through endochondral ossification
Endochondral ossification
Endochondral ossification is one of the two essential processes during fetal development of the mammalian skeletal system by which bone tissue is created. Unlike intramembranous ossification, which is the other process by which bone tissue is created, cartilage is present during endochondral...

.

Inner surface of the skull-cap

The inner surface of the skull-cap is concave and presents depressions for the convolutions of the cerebrum, together with numerous furrows for the lodgement of branches of the meningeal vessels.

Along the middle line is a longitudinal groove, narrow in front, where it commences at the frontal crest, but broader behind; it lodges the superior sagittal sinus, and its margins afford attachment to the falx cerebri
Falx cerebri
The falx cerebri, also known as the cerebral falx, so named from its sickle-like form, is a strong, arched fold of dura mater which descends vertically in the longitudinal fissure between the cerebral hemispheres....

.

On either side of it are several depressions for the arachnoid granulations, and at its back part, the openings of the parietal foramina when these are present.

It is crossed, in front, by the coronal suture
Coronal suture
The coronal suture is a dense, fibrous connective tissue joint that separates the frontal and parietal bones of the skull. At birth, the bones of the skull do not meet.-Pathology:...

, and behind by the lambdoidal, while the sagittal lies in the medial plane between the parietal bones.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK