Anterior Fontanelle Closure

The precise timing of the anterior fontanelle closure is quite variable and the research literature shows cases of closure from 6 months that may represent a normal variation in healthy babies 2 although early or late closure of a fontanelle is associated with various pathologies 3.

Anterior fontanelle closure. 1 posterior fontanelle generally closes 2 3 months after birth 2 sphenoidal fontanelle is the next to close around 6 months after birth 3 mastoid fontanelle closes next from 6 18 months after birth and 4 the anterior fontanelle is generally the last to close between 1 3 years of age in one recent human sample the anterior fontanelle was closed in most individuals by 31 months postnatally in another sample most individuals. During childbirth the flexibility of the sutures allows the bones to overlap so the baby s head can pass through the birth canal without pressing on and damaging their brain. Compared to data in older textbooks this suggests a trend towards earlier closure of the fontanelle.

The fontanelle allows the skull to deform during birth to ease its passage through the birth canal and for expansion of the brain after birth. The fontanelle at the top of the head anterior fontanelle most often closes between 7 to 19 months. The most common causes of a large anterior fontanel or delayed fontanel closure are.

The a nterior fontanelle takes the longest time after birth to close. The anterior fontanelle is generally the last to close between 12 18 months. These fontanelles will close between 6 and 18 months.

Received december 5 1949. It is the last to close. The fontanelles should feel firm and very slightly curved inward to the touch.

It will take between 12 to 18 months for the sutures to solidify here. The sphenoidal fontanelle is the next to close around 6 months after birth. The anterior fontanelle typically closes between the ages of 12 and 18 months.

The anterior fontanelle generally closes between 18 and 36 months of age. The average size of the anterior fontanel is 2 1 cm and the median time of closure is 13 8 months. The mastoid fontanelle closes next from 6 to 18 months after birth.