Infants normally have two fontanels at birth, the diamond-shaped anterior fontanelle at the junction of the coronal and sagittal sutures, and the posterior fontanelle at the intersection of the occipital and parietal bones. The posterior fontanelle usually closes by the 8th week of life, and the anterior fontanel closes by the 18th month of life on average. This term applies if there is delay of closure of the fontanelles beyond the normal age. The phenotype is Delayed cranial suture closure (HP_0000270, a Human Phenotype Ontology term). Also known as: Broad late closing cranial sutures, Delayed closure of fontanel, Delayed closure of fontanelles, Delayed closure of fontanels, Delayed closure of the fontanelles, Delayed fontanel closure, Delayed fontanelle closure, Late closing fontanelles.