Abstract：
BACKGROUND: The purpose of this study was to evaluate the therapeutic effect of modified clear Twin Block (CTB) aligner and traditional twin block (TB) appliance from skeletal, dentoalveolar and soft tissue changes in adolescents with skeletal class II malocclusion.
METHODS: A total of 80 adolescents, included in this study from two medical centres, were distributed into CTB group, TB group and control group based on the treatment they received. Lateral cephalograms at pre-treatment (T1) and post-treatment (T2) were measured by modified Pancherz\'s cephalometric analysis, and dentoskeletal and soft tissue changes were analysed by independent-sample t-test, paired-sample t-test, ANOVA test and Scheffe\'s Post Hoc test.
RESULTS: Seventy-five adolescents completed the study, including 32 in the CTB group, 32 in the TB group and 11 in the control group. Both CTB and TB treatment showed significant differences in most dentoskeletal and soft tissue measurements. Compared with the control group, improvements were observed in class II molar relationship through significant different in S Vert/Ms-S Vert/Mi in the CTB group (P < .01) and the TB group (P < .001), as well as deep overjet through significant different in S Vert/Is-S Vert/Ii in the CTB group (P < .001) and the TB group (P < .001). Besides, the CTB group also showed less protrusion of lower incisors and resulted in a more significant improvement in profile with fewer adverse effects on speaking, eating and social activities.
CONCLUSIONS: For adolescents with skeletal class II malocclusion, CTB appliance was as effective as TB on improving dentoskeletal and soft tissue measurements, featuring more reliable teeth control and patient acceptance.
METHODS: A total of 80 adolescents, included in this study from two medical centres, were distributed into CTB group, TB group and control group based on the treatment they received. Lateral cephalograms at pre-treatment (T1) and post-treatment (T2) were measured by modified Pancherz\'s cephalometric analysis, and dentoskeletal and soft tissue changes were analysed by independent-sample t-test, paired-sample t-test, ANOVA test and Scheffe\'s Post Hoc test.
RESULTS: Seventy-five adolescents completed the study, including 32 in the CTB group, 32 in the TB group and 11 in the control group. Both CTB and TB treatment showed significant differences in most dentoskeletal and soft tissue measurements. Compared with the control group, improvements were observed in class II molar relationship through significant different in S Vert/Ms-S Vert/Mi in the CTB group (P < .01) and the TB group (P < .001), as well as deep overjet through significant different in S Vert/Is-S Vert/Ii in the CTB group (P < .001) and the TB group (P < .001). Besides, the CTB group also showed less protrusion of lower incisors and resulted in a more significant improvement in profile with fewer adverse effects on speaking, eating and social activities.
CONCLUSIONS: For adolescents with skeletal class II malocclusion, CTB appliance was as effective as TB on improving dentoskeletal and soft tissue measurements, featuring more reliable teeth control and patient acceptance.
摘要：
背景：这项研究的目的是评估改良的透明孪生阻滞（CTB）矫正器和传统的孪生阻滞（TB）矫正器的治疗效果，青少年II类骨骼错牙合畸形的齿槽和软组织变化。
方法：共有80名青少年，包括在两个医疗中心的这项研究中，分为CTB组，结核病组和对照组根据他们接受的治疗。治疗前（T1）和治疗后（T2）的侧位头颅图通过改良的Pancherz头颅测量分析测量，通过独立样本t检验分析牙骨骼和软组织的变化，配对样本t检验，方差分析测试和Scheffe的事后测试。
结果：75名青少年完成了这项研究，CTB组32人,TB组32，对照组11。CTB和TB治疗在大多数牙骨骨骼和软组织测量中均显示出显着差异。与对照组相比,在CTB组（P<0.01）和TB组（P<0.001）中，通过SVert/Ms-SVert/Mi的显着差异观察到II类磨牙关系的改善，在CTB组（P<.001）和TB组（P<.001）中，通过SVert/Is-SVert/Ii的显着差异以及深超喷。此外,CTB组还显示出较少的下切牙突出，并导致轮廓显着改善，对说话的不良影响较少，饮食和社交活动。
结论：对于患有骨骼II类错牙合的青少年，CTB矫治器在改善牙骨骼和软组织测量方面与TB一样有效，具有更可靠的牙齿控制和患者接受。
方法：共有80名青少年，包括在两个医疗中心的这项研究中，分为CTB组，结核病组和对照组根据他们接受的治疗。治疗前（T1）和治疗后（T2）的侧位头颅图通过改良的Pancherz头颅测量分析测量，通过独立样本t检验分析牙骨骼和软组织的变化，配对样本t检验，方差分析测试和Scheffe的事后测试。
结果：75名青少年完成了这项研究，CTB组32人,TB组32，对照组11。CTB和TB治疗在大多数牙骨骨骼和软组织测量中均显示出显着差异。与对照组相比,在CTB组（P<0.01）和TB组（P<0.001）中，通过SVert/Ms-SVert/Mi的显着差异观察到II类磨牙关系的改善，在CTB组（P<.001）和TB组（P<.001）中，通过SVert/Is-SVert/Ii的显着差异以及深超喷。此外,CTB组还显示出较少的下切牙突出，并导致轮廓显着改善，对说话的不良影响较少，饮食和社交活动。
结论：对于患有骨骼II类错牙合的青少年，CTB矫治器在改善牙骨骼和软组织测量方面与TB一样有效，具有更可靠的牙齿控制和患者接受。
