Clinical Study Of Non-extraction Treatment Of Early Permanent Dentition Crowding In Different Orthodontic Treatment

Objective:By comparing the position changes of the dental arch,alveolar arch,incisors and molars of the patients treated with different orthodontic treatment systems before and after the maxillary is regularly arranged,analyze and investigate the different mechanisms of orthodontic treatment systems and clinical effects,thereby providing references for the establishment of the treatment scheme of juvenile crowded dentition and the selection of the correctional system in clinical practice.Methods: Selected 30 patients with crowded dentition from December 2014 to September 2016 in Shenyang Orthopedic Hospital.The screening standards as follows:(1)Patients' maxillary dentitions are complete,and they are in the initial period of the permanent teeth during which the second molars have not erupted nor yet been established;(2)Maxillaries are moderate crowded;(3)Acceptting non-extraction treatment,and in the treatment process without using the facebow,expansion screw,implant anchorage,TPA,interproximal enamel stripping and other auxiliary means;(4)Patients with good lips closed,no sucking,biting lip,tongue,mouth breathing and other bad habits;(5)Patients do not have history of orthodontic treatment,cleft lip and palate,congenitally missing tooth,supernumerary tooth and impacted tooth.According to the different treatment systems used in the course of treatment,the 30 standard-compliant patients were divided into 3 groups(G1,G2,G3): 10 patients were treated with CCO(Complete Clinical Orthodontics)system for G1 group;10 patients were treated with Damon system for G2 group;and 10 patients were treated with the traditional system of MBT(Discovery of Dentaurum)for G3 group.The plaster models were made and the X-ray cephalograms were taken respectively before the treatment(T0)and after the maxillary aligned(T1),Use the 3 Shape R700 3D scanner to scan the plaster models,and using the 3 Shape OrthoAnalyze analysis software measures and analyze the digital model.Import the data of X-ray cephalograms into the Dolphin software for marker mapping and data analysis.Apply the SSPS 19.0 software to do the statistical analysis of the results,and adopt paired t-test to compare the changes of the maxillary alignments in the groups;the differences among the groups were analyzed by independent samples t-test,and if P <0.05,then it had statistical significance.Results: The arch width of the patients' canine and premolars increased in all the three groups,and the width of the molars changed unobviously,and the change of the arch width has no significant differences among the three groups;the width of the patients' alveolar arch among all the three groups increased;compared with the MBT group,in the CCO system group and the Damon system group the width of the patients' first molar alveolar arches increased significantly,while their obliquity of first molars decreased significantly,the obliquity of first molars in the MBT group increased;before and after the maxillary aligned,the position of the first molars barely moved at all in the CCO group,the first molar distal movement was 1.38 mm in the Damon group,and the first molar mesial movement was 4.16 mm in the MBT group;compared with the MBT group,in the CCO system group and Damon system group the obliquity of the incisors and the angle of the incisors significantly decreased,the angle in the Damon group decreased the most followed by the CCO correction group,both of the obliquity of the incisors and the angle increased in the MBT group;the incisors position of the CCO group basically remain unchanged,the distal migration in the Damon group moved,the incisors in the MBT group moved labial migration.Conclusion: 1.In terms of the changes of the dental arches in the non-extraction treatment,there are no significant differences between the self-ligating system and the straight wire appliance.2.In terms of alveolar arch reconstruction,the self-ligating system has more advantages and more conformable to the physiological reconstruction than the straight wire appliance.3.The self-ligating system can control the orthodontic anchorage of the molar teeth better,the Damon system has obvious distal migration;the molars barely move in the CCO system treatment;the MBT system has mesial migration.4.The self-ligating system can control the labial inclination of the incisors and the position of the incisors better,the CCO system can show the anterior tooth torque better while controlling the labial inclination of the incisors;labial inclination of the incisors treated decreases the most in the Damon system treatment;the MBT orthodontic treatment of the anterior lip inclination and anterior labial migration.