Cranial base and the growth of the cranial vault: an experimental study on the rabbit.

Artificial premature synostoses of interparietal, temporoparietal and frontoparietal sutures was induced in 5-day-old rabbits in order to investigate the adaptive capacity of the synchondroseal cartilages. Ten control and 15 experimental animals were killed at the ages of 50 and 100 days. The lengths of occipital and sphenoid bones were significantly increased by 50 days but no longer at 100 days. The angle between the occipital and sphenoid bones was decreased and between the presphenoid and sphenoid bones increased by 50 and 100 days. The results indicate that the growth of the cranial base is to some extent adaptive to the growth of the neural tissues early in postnatal life, but as the growth of the cranial base synchondroses continues much longer than that of the brain the independent growth potential is manifest during the later period.