child’s skull

The skull bones of the fetus and child are separated by membranous spaces (fontanelles). They disappear during the course of ossification.

frontal bone

Flat skull bone forming the forehead and top of the eye sockets, and articulating especially with the parietal.

coronal suture

Joint connecting the frontal and parietal bones on each side of the skull; it ossifies during the growth years (the anterior fontanelle closes up).

anterior fontanelle

Membranous space between the frontal and two parietal bones; it closes usually at the age of two or three years. This is the largest of the fontanelles.

parietal bone

Flat cranial bone fusing especially to the frontal and occipital bones during the growth years.

posterior fontanelle

Membranous space between the occipital and two parietal bones; it closes at about the age of two or three months. This fontanelle is smaller than the anterior fontanelle.

occipital bone

Flat cranial bone fusing especially to the parietal bone and atlas (first cervical vertebra) during the growth years.

mastoid fontanelle

Membranous space between the parietal, occipital and temporal bones; it closes at about the age of 18 months. This fontanelle is smaller than the sphenoidal fontanelle.

sphenoidal fontanelle

Membranous space between the frontal, parietal, temporal and sphenoid bones; it closes at about the age of two or three months.