Objective To investigate the clinic effects and reliability of J-hook headgear with extraoral anchorage to push m olars backward. M ethods J-hook headgear was used as auxiliary device to correct A ngle Class Ⅱ m alocclusion for m ixed dentition at advanced stage or perm anent dentition at initial stage during growth spurt period. R esults The average adding interdental space at m olars was 4.75 m m , which m ade the crowding anterior teeth could be corrected, and the patients got Class Ⅰocclusal relationship, with the result that teeth extraction could be avoided. C onclusion J-hook headgear with edgewise appliance is one of convenient m ethods to correct A ngle Class Ⅱ m alocclusion without extracting teeth.
