The Analysis Of New Ribbon Arch Appliance In The Orthodontic Treatment Of Special Teeth Extraction Case

Objective: To analyse the clinical effect and treatment characteristics of the skeletal class?Angle class? division 1 malocclusion case's treatment with special design of teeth extraction by using the New Ribbon Arch Appliance to open occlusion, retract the upper anterior teeth, control the torque of the anteriors and improve the facial profiles. And provide theoretical basis for the clinical operations.Materials and methods: A case treated in Affiliated Union Hospital of Fujian Medical University was selected. The patient had been diagnosed as skeletal class? Angle Class?division 1 malocclusion.Female patient, aged 17, a convex facial profile, lower midline shifted to right by 1mm,?°deep overbite and ?°deep overjet. Bilateral molars and canies relationships were mild distal relationship. There were 3mm crowding in upper arch and 5mm crowding in lower arch. Occlusion, facial photographs and panoramic, lateral radiographs were taken before and after orthodontics treatment. Cephalometric data: U1-SN 129°,U1-L1 114.5°,Go Me-FH 21.9°,Go Gn-SN 26.2°, Z angle 75.5°,FCA 171.0°,MLA 113°,NLA° 88.6°, LL-E 0.4mm. Design : extraction of 17?27?35?45, retract upper anterior teeth, protract the lower molars, and close the space, adjust the occlusal finally.Result: After 18 months' treatment, overbite and overjet are normal with remarkable changes of the upper anterior's torque is achieved. Bilateral molars relationships are total Class III relationship, while the canies relationships are Class I. Cephalometric data after treatment: U1-SN has been decreased by 17.6°,U1-L1 increased by 10.4°,indicating the upper insior teeth has been retracted well,whereas Go Me-FH has been increased by 2.6°and Go Gn-SN by 3.1°,which indicates a clockwise rotation of mandible. L1-MP has been increased by 3° and the distance of L1-MP has been decreased by 2.3mm which means lower incisors are proclined and intruded. FCA has been decreased by 0.3 °, MLA increased by 3°, NLA increased by 8°, the distance of LL-E decreased by 2.1mm which suggests facial profile is improved. The patient is satisfied with the overcome of the treatment.Conclusion: This case of skeletal class?Angle class ?malocclusion is treated effectively by using the second-generation new ribbon arch appliance. Occlusion is opened rapidly, good torque of anterior teeth are achieved and facial profile improved.