Final answer:
The anterior fontanel is a soft spot on the top front of a newborn's skull, crucial for childbirth and head growth, which gradually ossifies and closes as the baby matures.
Step-by-step explanation:
The soft spot on the anterior part of a newborn's head is known as the anterior fontanel.
Fontanels are areas on a baby's head where the bones of the skull have not yet fully ossified, meaning they are not completely hardened into bone. These soft spots are essential for a newborn's birth as they allow the skull to be flexible enough to pass through the birth canal. The largest fontanel, located at the top front of the newborn's skull, is the anterior fontanel. This spot is diamond-shaped and is one of the two largest fontanels, with the other being the smaller triangular-shaped posterior fontanel at the back of the head. Over time, as the baby grows, these fontanels will close due to the process called ossification, where the fibrous connective tissue that forms the fontanelles gradually turns into bone. The posterior fontanel often closes within the first two or three months after birth, and the anterior fontanel typically closes between nine to 18 months after birth. This closing process is essential for protective reasons and allows for the normal growth of the child's brain and skull.