出典:Wikipedia
出典:『Wikipedia』 (2010/07/08 03:38 UTC 版)
Primary bone is the first bone tissue that appear in embryonic development and in fraction repair. Its characterized in its random position of collagen fibers. In most places in adults this tissue is replaced by secondary bone tissue except for example near the sutures of calvara or tooth sockets. The secondary bones have lower amount of osteocytes so primary bone is much more easily penetrated by x-ray.