What are the symptoms of the chin pressing on the anterior fontanelle

The fontanelle refers to the gap in the skull formed by the loose connection of the skull bones of infants and young children. During the healing process, some parents may not pay attention, and the chin may press on the anterior fontanelle. This area cannot be invaded, and external impact may have very serious consequences. Therefore, some adverse consequences are what parents are most concerned about. So, what are the symptoms of the chin pressing on the anterior fontanelle? Let’s take a look below.

Normal closure time of fontanelle

Under normal circumstances, the posterior fontanelle is very small or closed when the baby is born, only large enough to accommodate a fingertip, and closes at the latest 6 to 8 weeks after birth. The oblique diameter of the anterior fontanelle is approximately 1.5 to 2.5 cm at birth. After birth, as the head develops, the head circumference gradually increases and the anterior fontanelle also increases. Six months after birth, the skull gradually becomes smaller as it ossifies and usually closes between one and a half years old.

Early closure

In a very small number of babies, due to maternal infection during embryogenesis or other diseases, the brain is poorly developed and the head is small. The head circumference is small at birth, and the anterior fontanelle closes prematurely 5 to 6 months after birth, causing microcephaly. For a few babies, when they are 5 to 6 months old, the fontanelle is only the size of a fingertip and seems to be about to close, but in fact it has not ossified. This is not premature closure. As long as the head circumference is normal, not less than 46 cm at one year old and not less than 47 to 48 cm at two years old, it is normal and there is no need to worry.

Delayed closure

Babies grow very rapidly during infancy, and their bone development requires vitamin D and calcium. If they are not supplemented in time, they are prone to rickets. The anterior fontanelle of babies suffering from this disease still fails to close 18 months after birth. In a few babies, delayed closure of the anterior fontanelle is caused by hydrocephalus or other reasons leading to increased intracranial pressure, and they should go to the hospital for further examination.

Sunken fontanelle

The most common cause is dehydration in the baby's body. For example, if the baby does not replenish water in time after diarrhea, the baby needs to be replenished with fluids immediately. Due to various reasons, large doses of dehydrating agents are used to reduce intracranial pressure, which can also cause the anterior fontanelle to become sunken due to dehydration. The baby's body should be replenished with necessary water in time to prevent excessive dehydration from causing metabolic disorders in the body. Babies with long-term insufficient intake leading to malnutrition or chronic diarrhea often have obvious sunken anterior fontanelles.

Bulging anterior fontanelle

Under normal circumstances, the fontanelle is flat and soft. If the fontanelle is bulging, tight, accompanied by fever, vomiting, or even convulsions, it means that the baby's intracranial pressure is increased, which may be caused by intracranial infection (meningitis, encephalitis, etc.); drug factors, such as long-term use of large doses of cod liver oil, vitamin A or tetracycline, can also make the baby's anterior fontanelle appear full. After discontinuing vitamin A and tetracycline, the anterior fontanelle will gradually become flat.

Parents should closely observe the changes in their baby's anterior fontanelle. If the above abnormal conditions occur, go to the hospital for examination and treatment immediately to avoid delaying the disease and affecting the child's normal growth and development.