<P> During birth , fontanelles enable the bony plates of the skull to flex , allowing the child 's head to pass through the birth canal . The ossification of the bones of the skull causes the anterior fontanelle to close over by 9 to 18 months . The sphenoidal and posterior fontanelles close during the first few months of life . The closures eventually form the sutures of the neurocranium . Other than the anterior and posterior fontanelles , the mastoid fontanelle and the sphenoidal fontanelle are also significant . </P>
<P> During birth , fontanelles enable the bony plates of the skull to flex , allowing the child 's head to pass through the birth canal . The ossification of the bones of the skull causes the anterior fontanelle to close over by 9 to 18 months . The sphenoidal and posterior fontanelles close during the first few months of life . The closures eventually form the sutures of the neurocranium . Other than the anterior and posterior fontanelles , the mastoid fontanelle and the sphenoidal fontanelle are also significant . </P>
when do the fontanelle close on a baby
when do the fontanelle close on a baby
9 to 18 months
9 to 18 months