I will slightly correct the answer above. The arc is perfect in shape until the moment of installation. Then she takes the shape of the dentition. But since this very arc has a "memory", that is, it seeks to return to its original state, the teeth from its influence begin to move. With proper treatment, this movement should not be rapid. Otherwise, the teeth, not having time to gain a foothold in a new place, may come back.
Also, if necessary, you can change not only the position of the teeth, but also the bite. This is done using rubber bands that are attached to hooks and thereby close the jaws in the desired state. Over time, it becomes a habit to hold the jaw like this, even if the rubber bands are removed.
After removing the braces, you need to fix the teeth so that they do not return to their original state. To do this, use retainers, mouth guards
Not a doctor one iota, but since, alas, I dealt with braces, I dare to answer. Braces are glued to the teeth and attached to a metal arch that runs in front of the dentition. The arch is elastic and perfectly shaped. Thus, the elasticity of the arch pulls the incorrectly standing teeth to their proper place.
P.S. If over the past 30 years something has changed in this area, let the experts correct my answer! :-)
The doctor advised, but here it took a lot of money for braces, and buying an irrigator is an additional expense. Is it possible to get by? Or is it a must-have device when wearing braces? Thanks for the tips!