Macmillan A R, Tideman H
Mater Misericordiae Public Hospitals, South Brisbane, Australia.
Ann R Australas Coll Dent Surg. 1994 Apr;12:232-9.
Vertical stability following maxillary downgrafting in cleft patients is poor with an average relapse of 42 per cent (ranged 0-100 per cent). Overcompensation should, therefore, be undertaken with 2 mm added to the downgraft movement for bony relapse and 1 mm added to the downgraft movement for upper lip lengthening. The Tideman et al. method for advancement of the lesser maxillary segment is a very stable procedure (less than 8 per cent relapse). Semi-rigid fixation with plates, bone grafting and 'ramping' enhances stability; and freeway space assessment preoperatively is an important guide to relapse potential in the downgrafted cleft maxilla. All surgical prediction tracings should be done with the patient at the occlusal vertical dimension to prevent inadequate maxillary advancement and subsequent reverse overjet or excessive anterior incisor proclination developing with vertical relapse.
腭裂患者上颌骨下移植后的垂直稳定性较差，平均复发率为42%（范围为0 - 100%）。因此，应进行过度补偿，在骨块下移运动中增加2mm以应对骨块复发，在骨块下移运动中增加1mm以延长上唇。Tideman等人推进较小上颌骨段的方法是一种非常稳定的术式（复发率低于8%）。使用接骨板进行半刚性固定、植骨和“斜坡”技术可增强稳定性；术前评估息止间隙是预测下移植腭裂上颌骨复发可能性的重要指标。所有手术预测描记均应在患者处于咬合垂直距离时进行，以防止上颌骨前移不足以及随后出现反覆盖或垂直复发导致前牙过度前倾。
