Irregularity can be corrected, but as long as the teeth move, they must move up and down, because the teeth must be aligned up and down to be functional. Now your teeth are all aligned. If it moves, the alignment will change, destroying the original occlusion relationship. So it has to be moved up and down together.

There are no side effects of orthodontics, only complications. But if you pay attention to oral hygiene, it will be fine. Then it will be nothing!

Filling the teeth will not affect the correction. The teeth must be filled before correction!