The Single Jaw Extraction Treatment Of Angle's Class ? Division 1 In Adolescent

Objective: To evaluate the effectiveness of single jaw extraction used in Angle's class ? with self-ligating brackets in adolescent.Method: A male adolescent patient with class ? division 1 malocclusion enrolled to Dalian Doctor Oral clinic in 2013.Patient was 10 years old diagnosed with Angle's class ? division 1 malocclusion,poor oral hygiene;Upper incisors flared serious more than normal,maxillary normally developed,with mandible poorly grew.He exhibited typical Class ? division I features with convex facial profile,?° overjet and ?? overbite.Total crowding in upper arch was 9.6mm and lower arch was 0.4mm;midline is normal;Bolton index of anterior teeth is 77%,and full teeth is 90.4%.Treatment plan was drawn according to analysis result: extract 14,24.Self-ligating brackets technique was applied both upper and lower arch.Sliding mechanics was used in upper to retract anteriors.Meanwhile,Class ? elastic was used to adjust molar relationship.Slight crowding was relieved in lower arch.All space was closed and attain normal overjet and overbite.Remove appliance after intense adjustment.Vacuum-formed retainer was made both for upper and lower teeth.Pretreatment and post treatment cephalometric radiographs were traced,compared and analyzed.Result: Total course of treatment was 32 months followed by retention with vacuumformed retainer.Upper and lower arch were leveling and alignment.Overjet and overbite are normal.Harmonious facial profile.Midline is normal,and occlusal relationship of canine was normal,but occlusal relationship of molar was distal.Clinical records andcephalometric analysis was done to evaluate pre and post treatment changes in dentoalveolar structures and soft tissue,extraction spaces were closed.Dentition was well aligned and no obvious root resorption.Comparison of pre and post treatment cephalometric tracing indicated following changes:(1)changes of maxillary and mandibular: the SNA had little change,SNB increased2°,ANB decreased 2°.(2)upper incisor had obvious change,U1-SN decreased 5.4°.Lower incisor axis had decreased 5°.U1-L1 was 117° and had obvious change(3)Wits was 0.2,decreased 0.3mm,indicated that maxillary and mandibular had a harmonious relationship.(4)ULEP was 0.3mm,decreased 3.2mm.LLEP was-0.2mm,decreased 1.7mm and ULP decreased 1.5mm,LLP had no obvious changes,H angle was 13°,decreased 2°,indicated that the patient had a harmonious facial profile and nature lip relationship.(5)ANS-Me was 73.8mm,increased 6.8mm,indicated that the mandibular had a harmonious relationship.Conclusion: There are many methods to treat Angle's class ? division 1 malocclusion,making the diagnosis and treatment promptly and individually with different conditions is contribute to achieve harmonious facial profile and occlusion.For Angle's Class ? Division 1 Malocclusion in adolescent,self-ligating brackets,accompanied with single jaw extraction,can provide continue and stable development of the mandibular,meanwhile control the maxillary retreated,to keep overjet and overbite well...