Roll the Bones

I went to the dentist on Tuesday. He said that I have the jawbone of a fifteen-year-old. Apparently, as one gets older, the bone structure of one's jaws degrades significantly. But the bone structure of my jaws has not degraded, for whatever reason.

The condition of my bones is not newsworthy in and of itself. What stands out to me is that if I say I have the jawbone of a fifteen-year-old, it sounds as if I buried the other parts in the woods.