Petrukhina O, Laudemann K, Nafzger M, Ballon A, Kopp S, Sader R A, Landes C A
Stomatologiia (Mosk). 2011;90(3):50-3.
This retrospective study evaluated 34 patients pre- and ~20.5 months post expansion 3D scanned cast models with tooth-borne (ТВ, n1=16) and bone-borne (BB, n2=18) devices. Measurements were performed for transverse skeletal/dental maxillary widening, dental tipping and dental attachment loss.
T-Test in long-term effects: BB: bigger, symmetric transverse widening along the dental arch; bigger attachment loss in the frontal teeth, canines, 2nd premolars. molars; bigger dental tipping in the canines and 2nd molars; ТВ: asymmetric transverse widening along the dental arch; bigger attachment loss in the 1st premolars: bigger dental tipping in the premolars and 1st molars.
BB should be used whenever bigger transverse maxillary expansion is required, new distractor designs may reduce segmental inclination and initial expansion asymmetries, consequently, eliminating the related attachment loss from secondary orthodontic tooth movements for arch alignment. ТВ devices showed minor expansion with good periodontal attachment, yet attachment loss in the first premolars must be critically seen in bigger expansion distances.
这项回顾性研究评估了34例患者,在使用牙支持式(ТВ,n1 = 16)和骨支持式(BB,n2 = 18)装置进行扩弓前及扩弓后约20.5个月时的三维扫描石膏模型。对横向骨骼/牙齿上颌扩弓、牙齿倾斜和牙齿附着丧失进行了测量。
长期效果的T检验:BB:沿牙弓的横向扩弓更大、更对称;前牙、尖牙、第二前磨牙、磨牙的附着丧失更大;尖牙和第二磨牙的牙齿倾斜更大;ТВ:沿牙弓的横向扩弓不对称;第一前磨牙的附着丧失更大;前磨牙和第一磨牙的牙齿倾斜更大。
当需要更大的上颌横向扩弓时应使用BB,新的扩弓器设计可能会减少节段倾斜和初始扩弓不对称,从而消除用于牙弓排齐的二次正畸牙齿移动相关的附着丧失。ТВ装置显示扩弓较小但牙周附着良好,然而在更大的扩弓距离时,第一前磨牙的附着丧失必须受到严格关注。