Complex sentence: Although cranial sutures appear to be wide, this reflects hypomineralization of the skull, and there is often "functional" craniosynostosis; and if the patient survives infancy, these sutures can permanently fuse.
Split into simpler sentences: Although cranial sutures appear to be wide, this reflects hypomineralization of the skull, and there is often "functional" craniosynostosis. If the patient survives infancy, these sutures can permanently fuse.