When does an infant's anterior fontanel close?

The anterior fontanel is an anatomical structure in infants and young children. If the fontanelle closes too early or too late, it is an abnormal phenomenon in the development of a child.

The anterior fontanel is the quadrilateral area at the front of the heads of infants and young children, located between the two growth lines (cranial joints) where the bones of the skull meet.
Anatomically, fontanelles in children are spaces covered by elastic fibrous membranes. The fontanelle is formed when three or more bones of the skull are located close together, between these bones, and the elastic fibrous membrane covers this space and connects the bones together. Children are born with a total of 6 fonts: anterior, posterior, two mastoid and two sphenoid (however, only the anterior fontanel is the most significant, the posterior fontanel is usually very small and not very numerous. significance, the remaining four fontanelles receive little attention, even in many children they are closed since the last weeks of pregnancy).

The fibrous structure not only holds the bones of the skull together, but also an elastic seam between the bones of the skull. Thanks to this fibrous membrane, the baby's head can change its size and shape to suit the mother's vaginal tract during labor and delivery (for a more favorable birth). Besides, when the baby is born, the fontanelle also acts as a cushion to protect the baby's brain from external shocks if it falls.
Immediately after birth, the anterior fontanel measures 2.5 cm x 2.5 cm (ranging from 0.6 cm to 3.6 cm), and can be up to 5 cm x 5 cm wide. Because the fontanelle is covered by a fibrous membrane, it is not dangerous for an adult to touch the fontanelle of a child. Parents can wash their children's hair and perform common actions such as wearing a hat or combing their hair without worrying about damaging the fontanelle.

The brain size of young children increases very quickly, when the baby is 6 months old, the volume of the baby's brain doubles that at birth, and triples when the child is 30 months old. The fontanel and elastic membrane are the factors that facilitate the skull to change in accordance with the rapid development of the brain.
A US study done in 1949 on the time of anterior fontanelle closure in 1677 children showed that the anterior fontanel fontanelle closed in the period of 4 - 26 months, of which: 90% closed at the age of 7 - 19 months, 41 .6% paid in the first year of life, 2.7% paid at 6 months and 13.5% paid at 9 months.
The anterior fontanel usually widens during the 2nd to 3rd week and then gradually closes. Usually the anterior fontanelle closes by the time a child is 14 months old, in most cases it is closed by the time a child is 19 months old, but it can close any time between 4 and 26 months (or 3 months) months and 24 months depending on documents and research). Normally the fontanel looks flat or slightly sunken.

A child's fontanelle closing too early or too late is a sign of disease.
If the fontanelles and fissures close late, do not close or widen with the age of the child, it is an unusual phenomenon, indicating the possibility of slow bone ossification due to poor thyroid function, or rickets, kidney failure. nutrition , or caused by abnormal brain enlargement.
If the child's anterior fontanel closes prematurely, it is not necessarily abnormal. In some cases, although the fontanelle closes prematurely, the baby's head circumference is still within the norm, which is not abnormal, however, the child needs to be carefully monitored to make sure that the baby's head circumference is growing. grow at a reasonable rate. If a baby's head circumference begins to fall below the desired reference value, such as in the 50th percentile at birth or in the 10th percentile some time later, the Further evaluation should be done to find the underlying medical cause for the premature closure of the fontanelle. Early closure of the fontanelle can cause head deformity, harm the development of the skull and brain, and even increase intracranial pressure.
The process of diagnosing and finding the cause of the child's fontanel closure early includes clinical examination and implementation of paraclinical techniques such as X-ray, computed tomography,... Usually with cases requiring intervention. The intervention will have to be surgical intervention, but the method of intervention will need to be considered by the doctor on a case-by-case basis, because it depends on the time the fontanelle closes, the cause of the fontanel closure, and the overall condition. children and accompanying diseases (if any). After intervention, children still need to be monitored and re-examined regularly to ensure that their skull and brain can develop normally. Therefore, in order to ensure the health of children, parents need to find a reputable hospital that specializes in Pediatrics and has adequate facilities to conduct in-depth examination and treatment.

Children need to provide enough elemental zinc/day for them to eat well, reach the correct height and weight and exceed the standard. Zinc plays a role in affecting most biological processes taking place in the body, especially the breakdown of nucleic acids, proteins... Organs in the body when zinc deficiency can lead to a There are a number of diseases such as neurological disorders, irritability, etc. Therefore, parents need to learn about the role of zinc and guide them to appropriate zinc supplements for their children.
In addition to zinc, parents also need to supplement their children with other important vitamins and minerals such as lysine, chromium, B vitamins,... errands.
Please regularly visit Vinmec.com website and update useful information to take care of your baby and family.

Article referenced source: stanfordchildrens.org