ABSTRACT
Superior aspect The vault (roof of the cranium) is crossed by three sutures (Fig. 18.1). The coronal suture separates the frontal bone from the two parietal bones posteriorly. The midline sagittal suture separates the two parietal bones. Its junction with the coronal suture, the bregma, is incompletely ossified at birth and can be felt as a diamond-shaped deficiency known as the anterior fontanelle. This closes at about 18 months of age. The lambdoid suture separates the two parietal bones and the occipital bone posteriorly, and meets the sagittal suture at the lambda. This, too, is not ossified at birth and presents as a small bony deficiency, the posterior fontanelle, which closes by the 3rd to 6th month.
