Recent research has found that our jaws actually shrink with age. After taking plaster molds of the teeth of dental students every ten years for forty years, they found that every jaw mold showed that there was less and less room for the teeth.
This crowdedness comes from the jaws shrinking, primarily the lower jaw, both in length as well as width. The reduction is only in millimeters, but if you already have a tight fit with your teeth, those millimeters are crucial.
One researcher pointed out that wisdom teeth cannot be blamed for this because the subjects who had their wisdom teeth removed experienced relatively the same amount of shrinking.
How much a jaw shrinks depends on the person, but for some people–as suggested above–the changes can impact them enough to detect that something is different with their bite. One of the researchers noted that it is good to know that this is normal, so it is something all dentists can tell their patients if problems arise. It’s also something that dentists should take into consideration when planning major bite reconstruction with their patients.
Now, this study hasn’t found a reason as to why the jaw shrinks, although the researchers believe that the change is most likely caused by both genetic and anatomical factors, such as the shape of one’s bite.
Still…it makes for great trivia.