Does a Later Closure of the Fontanel Indicate Higher Intelligence?

The saying that "the later the fontanel closes, the smarter the child is" definitely does not hold true. Whether a child is intelligent or not is closely related to the degree and state of their brain development, rather than the timing of fontanel closure. The fontanel is the largest gap between the two cranial sutures at the fetal head. The large fontanel, also known as the anterior fontanel, is a rhomboid-shaped bony defect formed by the two frontal bones, two parietal bones, and the frontal suture, coronal suture, and sagittal suture. The small fontanel, also known as the posterior fontanel, is a triangular-shaped bony defect formed by the two parietal bones, occipital bone, and cranial sutures. The anterior fontanel is approximately 1.5 to 2.5cm in size at birth (measured as the distance between the midpoints of the opposite sides). It gradually enlarges slightly as the head circumference increases in the first few months of life, and then gradually ossifies and becomes smaller after 6 months. In normal, healthy children, the anterior fontanel closes between 12 and 18 months of age. The posterior fontanel, which is a triangular gap formed by the parietal and occipital bones, is already closed or very small at birth and typically closes within 6 to 8 weeks after birth. If the fontanel fails to close within the normal timeframe, it is important to be more vigilant for pathological conditions such as common vitamin D deficiency rickets, calcium deficiency, hypothyroidism, especially congenital hypothyroidism, hydrocephalus due to pathological conditions, and even chromosomal disorders. If delayed fontanel closure is observed, it is essential to promptly monitor the head circumference and conduct neuropsychological development assessments to determine the presence of any pathological conditions. Delayed fontanel closure should be investigated for underlying causes and treated promptly to avoid any adverse effects on the child's growth and development. Many diseases, such as rickets, hydrocephalus, hypothyroidism, chromosomal disorders, vitamin D and calcium deficiency, and neonatal rickets, can cause delayed fontanel closure in children. Most cases are due to calcium and vitamin D deficiency, which can manifest as symptoms such as excessive sweating, easy startled responses, and significant crying at night. Some cases may also lead to occipital hair loss, skull softening, and a "ping-pong" feeling when pressing the occipital or parietal areas. If a child has a large fontanel and delayed closure, it is recommended to have them evaluated by a healthcare professional, including blood tests, to confirm the diagnosis and initiate appropriate calcium and vitamin D supplementation.