Is it possible to get orthodontic treatment?

I had orthodontic treatment 15 years ago, which lasted about a year and a half. At that time, I wasn't very satisfied with the results, but I had no choice and it was better than before, so I just lived with it. However, as time has passed, my teeth don't look straight, and the shape is quite bothersome. Is it possible to undergo re-orthodontic treatment in this case? I’ve never heard of someone undergoing re-orthodontic treatment, so I’m curious. Has anyone experienced this?