Lossdörfer Stefan, Schwestka-Polly Rainer, Wiechmann Dirk
Department of Orthodontics, Rhenish Friedrich-Wilhelm University of Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany,
J Orofac Orthop. 2013 Sep;74(5):381-96. doi: 10.1007/s00056-013-0163-y. Epub 2013 Aug 23.
Bracket slots and orthodontic archwires offering high dimensional precision are needed for fully customized lingual appliances. We aimed to investigate whether high-precision appliances of this type enable dentoalveolar compensation of class III malocclusion so that lower incisor inclination at the end of treatment will closely match the anticipated situation as defined in a pretreatment setup.
This retrospective study included a total of 34 consecutive patients who had worn a fully customized lingual appliance to achieve dentoalveolar compensation for class III malocclusion by intermaxillary elastics, or proximal enamel reduction, or extraction of teeth in one or both jaws. Casts fabricated at different points in time were three-dimensionally scanned to analyze how precisely the lower incisor inclinations envisioned in the setup were implemented in clinical practice.
Aside from minor deviations of ±3.75°, the lower incisor inclinations were clinically implemented as planned even in patients with major sagittal discrepancies.
Treatment goals predefined in a setup of dentoalveolar compensation for class III malocclusion can be very precisely achieved via a customized lingual appliance. Correct planning can prevent undesirable lingual tipping of the lower incisors. This finding should not encourage a more liberal use of dentoalveolar compensation, but it should heighten clinicians' awareness of how essential it is to sufficiently consider the individual anatomy of the dentoalveolar complex during treatment planning.
完全定制的舌侧矫治器需要具有高尺寸精度的托槽槽沟和正畸弓丝。我们旨在研究这种高精度矫治器是否能实现Ⅲ类错牙合的牙槽骨代偿，使治疗结束时下颌切牙倾斜度与治疗前设定中预期的情况紧密匹配。
这项回顾性研究共纳入34例连续患者，这些患者佩戴了完全定制的舌侧矫治器，通过颌间弹力牵引、邻面釉质减径或拔除单颌或双颌牙齿来实现Ⅲ类错牙合的牙槽骨代偿。对在不同时间点制作的模型进行三维扫描，以分析在临床实践中，设定中设想的下颌切牙倾斜度的实现精度如何。
除了±3.75°的微小偏差外，即使是矢状面差异较大的患者，下颌切牙倾斜度在临床上也按计划实现。
通过定制的舌侧矫治器可以非常精确地实现Ⅲ类错牙合牙槽骨代偿设定中预先定义的治疗目标。正确的计划可以防止下颌切牙出现不良的舌向倾斜。这一发现不应鼓励更随意地使用牙槽骨代偿，但应提高临床医生在治疗计划过程中充分考虑牙槽骨复合体个体解剖结构的重要性的认识。
