A study of double keyhole loops in mandibular first molar moving forward bodily
Pan Mei-zhen;Xiao Hui;He Xu-shun;Tan Jia-li;Guanghua School of Stomatology,Sun Yat-Sen University;Department of Orthodontics,Guangdong Provincial Stomatological Hospital;
Objective: To evaluate the treatment outcome of double keyhole loops in moving mandibular first molar forward,which to correct the Angle Class Ⅱ disorder. Methods: Sixteen Class Ⅱ patients aged from 14-25 years were chosen,that all the lower second premolars of these cases were extracted with average fine height and width of bone in the extraction spot. Double keyhole loops were used to move the mandibular molars forward in order to correct distal molar relationship.Lateral cephalometric radiographs were taken and cephalometric analysis were done before and after treatment. Data were analyzed by using pairedt-test. Results: All the lower molars moved forward bodily with no inclination or elevation,and extraction spaces were closed with satisfied contact area between lower first premolars and first molars. Conclusion: It is efficient to use double keyhole loops in moving the distal first molar forward bodily.