背景:每天使用22小时的透明对准器(CA),创建一个咬合块的效果。这项工作旨在(i)分析治疗开始前的咬合变化,在第一组CA和使用其他矫正器后;(ii)将计划的咬合接触与第一组CA后获得的咬合接触进行比较;(iii)分析仅在夜间使用CA3个月后达到正畸目标后发生的咬合变化;(iv)评估和表征哪些牙齿移动不允许在第一组矫正器结束时完成治疗,最后(v)验证咬合接触的变化与区域和参数之间的可能关系,例如病例复杂性和面部生物型。
方法:定量,比较,实施观察性纵向队列研究设计,以评估接受CA的病例的临床数据和复杂性水平.招募了82个人的非概率和便利样本。正畸错牙合特征被归类为简单,中度,或基于使用Invisalign®评估工具的Align®建议的复杂校正。根据Invisalign®标准,患者只需要一个复杂的问题,他们的病例被归类为复杂。Meshlab®v.2022.02,ClinCheck®Pro6.0版,My-Itero®2.7.9.6015dplus,和IBM®SPSS统计软件(社会科学统计程序),Windows版本27.0是所使用的软件。
结果:从正畸治疗开始前(T0)到治疗结束(T1),观察到面积和咬合接触数量的统计学显着减少。在高发散(28.24[15.51-40.91])和低发散(16.23[8.11-24.97])生物型(p=0.031)之间,咬合面积的变化(从T0到T1)具有统计学差异。在T1中发现前接触的过度发散(4.0[2.0-5.0])和正常发散(5.5[4.0-8.0])组之间存在显着差异(p=0.044)。获得的前接触显著高于计划(p=0.037)在T1和T2之间,咬合面积的统计学显著增加,观察到后部和总接触。
结论:咬合接触和面积减少,在第一组结束时或在使用额外的对准器之后。获得的前咬合接触高于计划,而获得的后咬合接触则高于计划。完成治疗的最困难的牙齿运动是扩张,旋转,和后挤压。在完成正畸治疗(T1)至3个月后(T2)仅在夜间使用额外的矫正器,后咬合接触明显增加,这可能是由于在此期间牙齿的自然沉降。
BACKGROUND: Clear aligners (CA) are used 22 h daily, creating a bite-block effect. This work aims to (i) analyze occlusal changes before the beginning of treatment, after the first set of CA and after the use of additional aligners; (ii) compare planned occlusal contacts with the ones obtained after the first set of CA; (iii) analyze the occlusal changes occurred after reaching the orthodontic goals after 3 months of using CA only at night; (iv) evaluate and characterize which tooth movements did not allow the treatment to be completed at the end of the first set of aligners, and finally (v) verify the possible relation between the changes in occlusal contact and areas and parameters such as
case complexity and facial biotype.
METHODS: A quantitative, comparative, and observational longitudinal cohort study design was implemented to evaluate the clinical data and the complexity levels of cases receiving CA. A non-probabilistic and convenience sample of 82 individuals was recruited. The orthodontic malocclusion traits were classified as simple, moderate, or complex corrections based on the basis of the Align® recommendations with the Invisalign® evaluation tool. According to the Invisalign® criteria, patients need only one complex problem for their
case to be classified as complex. Meshlab® v. 2022.02, ClinCheck® version Pro 6.0, My-Itero® version 2.7.9.601 5d plus, and IBM® SPSS Statistics software (Statistical Program for Social Sciences), version 27.0 for Windows were the software® used.
RESULTS: A statistically significant decrease in area and occlusal contacts number were observed from before the start of orthodontic treatment (T0) to the end of treatment (T1). The changes in the occlusal area (from T0 to T1) were statistically different between hyperdivergent (28.24 [15.51-40.91]) and hypodivergent (16.23 [8.11-24.97]) biotypes (p = 0.031). A significant difference between the hyperdivergent (4.0 [2.0-5.0]) and normodivergent (5.5 [4.0-8.0]) group was found in T1 for the anterior contacts (p = 0.044). Anterior contacts obtained were significantly higher than the planned (p = 0.037) Between T1 and T2 statistically significant increases of occlusal areas, posterior and total contacts were observed.
CONCLUSIONS: Occlusal contact and area were decreased, either at the end of the first set or after the use of additional aligners. Anterior occlusal contacts obtained were higher than planned as opposed to posterior occlusal contacts obtained. The hardest tooth movements to achieve to complete the treatment were distalization, rotation, and posterior extrusion. After completing orthodontic treatment (T1) to 3 months after (T2) using additional aligners only at night, posterior occlusal contacts were significantly increased, which could be due to the natural settling of the teeth in this period.