I did it in a private hospital in Cangzhou. The dentist came out of the big hospital to do private work. His technique is quite good. I just fixed it. At that time, it cost 3,000 yuan and took less than 1.5 years to repair. Now I have an invisible retainer, that is, an alveolar cavity with transparent upper and lower teeth, which is made according to the shape of your last fixed tooth. You can put it on your teeth and you can't see it from a distance. 6666.6668666661If you look closely, you will find that it is quite bright, with a little thickness, and it is not intentionally invisible.