Anterior fontanelle

The largest fontanelle in the skull is called the anterior fontanelle (a.k.a. bregmatic fontanelle). It is formed by the frontal and parietal bones coming together. Its size ranges from 0.6 cm to 3.6 cm. Normally, the anterior fontanelle closes between 13 to 24 months after birth. In the adult skull, the closure of this fontanelle marks the point where the sideways coronal suture meets the midline sagittal suture. This point is known as bregma.

Fontanelles are vital in facilitating the movement and molding of the skull during labor, and they also enable the brain to grow as it develops after birth. Monitoring the anterior fontanelle is crucial in clinical settings as it provides valuable information about the well-being of a newborn. If the fontanelle appears sunken, it could indicate dehydration, whereas a bulging fontanelle may suggest an increase in intracranial pressure.