The retrospective study of treatment the adult Angle's classIIdivisionImalocclusion with the single maxillary extraction orthodontics

Objective: To investigate the better indications of single maxillary extraction orthodontics used for the adult Angle's classⅡdivisionⅠmalocclusion。Method:16 classⅡdivisionⅠadult patients were treated by single maxillary extraction orthodontics,The clinic material include photo、model and cephalometric before and after treatment were col- lected and evaluated.Result:The effect of 11 patients was satisfaction.The profile of up lip protrusion impressed signifi- cantly.Molar and canine relationship was whole distal and neutral respectively.The anterior overjet and overbite was nor- mal.All of these cases had the similar clinic characteristic before treatment.Condusion:It is easy achieving a satisfied ef- fect for the adult Angle's classⅡdivisionⅠmalocclusion which characteristic was upper arch protrusion,anterior overjet not more than 9 mm,crowing of lower arch space analysis less than 4mm and molar relationship of beginning distal occlu- sion to use single maxillary extraction orthodontics.