how come despite being straightened via braces or invisaligners, our teeth always naturally want to shift back, even if the original position was full of spacing or crowding?

Question

I know for some of us who don’t have naturally straight adult teeth that the way they grew in pre-treatment is technically *our* “natural”, but why do they still want to move back even if the original position was excessively spaced or crowded? Wouldn’t the ortho treatment make the teeth more “comfortable”, for lack of a better term?

In: Biology

Answer 1

This is difficult to explain in terms a five year old would understand but to give a brief summary

1) Your teeth aren’t directly anchored into bone but instead the root is tethered by millions of little fibers (PDL) which makes them easy to move. By contrast, a dental implant which is directly anchored into the bone will not move

2) Your bone, in general is constantly remodeling throughout your life. Osteoblasts build bone, osteoclasts resorb bone and this process is in continual flux depending on a variety of stimuli that naturally occur

3) Given that your teeth in particular aren’t directly attached to the bone and the fact that the bone in the top (maxilla) and bottom (mandibular) parts of your jaw is continually moving – the effects you notice from your teeth shifting are much more pronounced

That’s a very surface level overview without getting into signaling pathways, traumatic stenosis, etc.