I'm currently expanding my arches at Pangyo Balance Dental Clinic, but they say it's not removable for adults, but the device is different. It just pinches the teeth and opens them well without having to put in screws. The
 place I used to do it was at Na Adult, but for some reason, I couldn't get it to open well because I didn't have enough strength. ㅡㅡ They went bankrupt there, and
 they are doing it at Balance Dental Clinic. It's at the level of a university hospital, and the system is good and good. It's not expensive, and it's a life-long dental clinic. I'm not promoting it, but I really recommend it.
 Don't just drive in the screws~