Combined Maxillary Protraction And Class Ⅲ Traction Treatment For Skeletal Class Ⅲ Malocclusion

Objective: To investigate the clinical effect of the protraction combined class Ⅲtraction for correction of the skeletal anterior crossbite.Methods: A case of11year old female with skeletal anterior crossbite wasadmitted to Dalian Dr. dental clinic in2009.On clinical examination the patient hadslight maxillary deficiency and excess mandibular development, mesial molarrelationship, concave facial profile. The patient was treated by protraction orthopedictherapy in combination with class Ⅲ traction appliance. The pre treatment and posttreatment cephalograms and models were analyzed.RESULTS: Total treatment duration was24months. After application ofprotractionombined with class Ⅲ traction to promote the development of the maxilla,with the MBT straight wire appliance to correct the malocclusion, so that patient’santerior teeth crossbite is corrected,molar relationship is class I and concave profile isimproved. the increase in SNA was by5.3°,SNB by3.1°, ANB by2.2°, ANS-Ptm by4mm and wit’s value by2.9mm. There was labial tilting of upper incisors, lingualinclination of the lower anteriors, increase in posterior facial height. a littlecounterclockwise rotation of Mandibular plane and a proper occlusion.Conclusion: Skeletal anterior teeth crossbite treated by the protraction combinedwith class Ⅲ traction, give full play to the orthopedic effect of protraction, andpromotes maxillary growth at the same time establishing a good overbite, overjet andclass I molar relationship overall providing a good clinical result.