The Analysis Of Efficancy Pre-and Post-treatment Of Class Ⅱ With Edgewise Appliance

Objective:To investigate dental and craniofacial changes in soft and hard tissue and facial profile changes in maxillary protrusion and borderline crowding classⅡmalocclusion patient after orthodontic extraction treatment.Materials and method :A female case classⅡmalocclusion was selected from DaLian Ortho clinic in 2006,who was 11.6 years old. maxillary protrusion,normal mandible, mental region hypodevelopment, right buccal segment relationship: cusp-to-cusp classⅡrelationship,life buccal segment relationship: classⅠrelationship, mild crowded of upper arch. Uptake x-ray lateral radiographic films pre-and post-treatment in a month.39 hard and soft tissue marked points of cephlometric radiographs were drawed in a period time.25 typical measurements were selected from Beijing Medical University,Tweed,Wits analysis ,so as to observe the changes between sagittal and vertical dimension from pre-and post- treatment.The patient was extracted four second premolar maxillary and mandi- bular with edgewise appliance.Results: The course of orthodontical treatment is 21 months. Compared the changes between pre-and post-treatment: Molar relationship changed from classⅡinto classⅠrelationship, classⅡskeletal facial profile was improved;SNA decreased 1.28°,SNB increased 0.2°,ANB decreased 1.48°;Overjet decreased 2mm;NA/PA decreased 3.54°(decreased from11.71°to8. 17°), There are obvious changes in maxillary protrusion. The vertical relationship was improved, the angle of MP/SN is reduced, The mandibular plane was slightly counterclockwise rotation; The profile of soft tissue improved obvious, which changed from convex surface type tending to directly facing type. The NLA increased from89.52°to 97.92°,The Z angle increased from65.48°to67.75°,The angle of Ns-Sn-Pos decreased from 22.5°to 13.5°.The patient and her parents were satisfied with the result of ortho- therapy after treatment.Conclusions: Skeletal ClassⅡmalocclusion with maxillary protrusion and midrange crowed of maxillary can be treated successfully by edgewise appliance with extraction four second premolar. The result can be satisfied from the improved; ClassⅡSkeletal and ClassⅡmolar relationship, over- jet, The profile of soft tissue.