chǐ liè jiǎo zhèng qì
see 牙齒矯正器|牙齿矫正器[ya2 chi3 jiao3 zheng4 qi4]
齿
chǐ
tooth
列
liè
to arrange
矫
jiǎo
to correct
正
zhèng
straight
器
qì
device
Review