I want to correct my teeth ... but my teeth change so slowly that I haven't finished changing them. I can't correct them =A= According to my classmates, Hengshan Dental Clinic is cheap, but it hurts. Then Jing 'an District Children's Hospital is said to have the same facilities as the Ninth Hospital, but it is cheaper not to queue up. I didn't ask if it hurts, but since the hospital in charge of children should be quite good.