When do fontanelles ossify

When do Fontanelles and cranial sutures close? Generally Fontanelles close in this order: I. Posterior Fontenelle around 2 — 3 months of age II.

Sphenoidal Fontanelles around 6 months of age III. Mastoid Fontanelles around 6 — 18 months of age IV. And if the ossification occurs too early? Some children may suffer from premature fusion of sutures and Fontanelles, a condition called Craniosynostosis.

Did you know that? You must be logged in to post a comment. Skip to content. Certainty Style Key. Certainty styling is being phased out topic by topic. Hover over keys for definitions:. What is MOCA? Human Uniqueness Compared to "Great Apes":. Human Universality:. Individual Universal All Individuals Everywhere. MOCA Domain:. Anatomy and Biomechanics.

Melanie Beasley. Possible Appearance:. Probable Appearance:. References Metopic suture of Taung Australopithecus africanus and its implications for hominin brain evolution , Falk, D. The evolution of hominin ontogenies. Brain size at birth throughout human evolution: a new method for estimating neonatal brain size in hominins. The morphogenesis of wormian bones: a study of craniosynostosis and purposeful cranial deformation. A juvenile early hominin skeleton from Dikika, Ethiopia. Brain ontogeny and life history in Homo erectus.

Early brain growth in Homo erectus and implications for cognitive ability. The Juvenile Skeleton , Scheuer, L. Avery's Diseases of the Newborn. Updated by: Neil K. Editorial team. Fontanelles - sunken. Sunken fontanelles are an obvious curving in of the "soft spot" in an infant's head. The fontanelle in the back of the head posterior fontanelle most often closes by the time an infant is 1 or 2 months old.

The fontanelle at the top of the head anterior fontanelle most often closes within 7 to 19 months. Reasons a child may have sunken fontanelles include: Dehydration not enough fluid in the body Malnutrition. When to Contact a Medical Professional. What to Expect at Your Office Visit. The provider will perform a physical exam and ask questions about the child's symptoms and medical history, such as: When did you first notice that the fontanelle looked sunken? How severe is it?

How would you describe it? Which "soft spots" are affected? What other symptoms are present? Has the baby been ill, especially with vomiting , diarrhea , or excessive sweating? Is the skin turgor poor?