The influence of senescence on craniofacial and cervical morphology in humans.

This study discusses the morphologic evolution of the cranio-facial and cervical bone structures throughout life. A cephalometric study was made on lateral radiographs. The population studied included 84 males and 102 females. Ages ranged from 21 to 101. The cranial structures, superior facial structure, mandible and cervical vertebral column were successively examined. The anteroposterior diameter of the calvarium does not seem to undergo any modification during life. On the other hand, a highly significant increase of the thickness of this structure can be noted. The upper facial structure presents some modification, namely a significant increase of its posterior height. The palatine processus seems to change direction and pivot downwards and forwards. The maxillary sinus does not undergo any changes. The mandible, which is stable in its major axes, shows more malleable sectors which are more especially situated at the level of its body. The study of the cervical vertebral column reveals a loss of overall height, and an increase in the lordosis. The most numerous and most evident morphologic modifications were observed around the age of fifty in both males and females. The fact that these transformations are always commoned and greater in the latter reveals the plausible influence of the menopause. It appears that bone structures of membranous origin are the site of significant modifications compared with structures of endochondral origin, which benefit from a greater stability.