Effects Of Extracting Cases Of Bimaxillary Protrusion By Combined Transpalatal And Nance Arch Intra-oral Anchorage

The specific characteristics of bimaxillary protrusion malocclusion can include a lip-closing inadequacy, facial profile convexity, and mental profile retrusion which may severely affect the patient's facial appearance. There is a higher incidence of this condition in China than among people from European or Japanese decent. However there are certain conditions such as bimaxillary protrusion where the profile convexity and dental arches can be treated orthodontically to produce a positive effect. In order to treat bimaxillary protrusion we should retract the upper and lower anterior teeth as much as possible by making full use of the extraction space. This retraction and control of the mesial movement of the anchorage molars is our main objective in the treatment. Therefore, the purpose of this study is to discover a stable and effective way to create a simple and comfortable apparatus for reinforcing the molar anchorage during orthodontic treatment to the patients with bimaxillary protrusion.A total of 75 patients with Class I malocclusion and bimaxillary protrusion, age 12-26, were selected and treated with the TPA, Nance arch and combined transpalatal-Nance arch on reinforcing anchorage. After the...