When do the anterior and posterior fontanels of a normal newborn typically close?

The correct information regarding the closure of the anterior and posterior fontanels in a normal newborn is that the anterior fontanel typically closes between 12 to 18 months of age, while the posterior fontanel usually closes much sooner, typically by the end of the second month of life.

The anterior fontanel, being a larger and more prominent soft spot located on the top of the head, allows for brain growth and flexibility of the skull during childbirth. Its later closure at approximately 12 to 18 months allows for continued development of the brain during infancy and early childhood.

On the other hand, the posterior fontanel is smaller and located at the back of the skull, and its early closure by the end of the second month reflects the rapid growth and hardening processes of the skull that are necessary for supporting the developing brain.

This understanding is crucial for monitoring the growth and development of infants, as abnormal closure times of these fontanels can indicate potential underlying issues with cranial development or brain growth.