腭横缝牵张成骨延长硬腭的实验研究

目的传统腭裂软组织后推延长手术由于瘢痕挛缩和缺乏骨性支持而难以维持软腭的正常长度、位置和发育，手术损伤和瘢痕还导致面部生长障碍。本研究旨在用缝牵张技术延长硬腭，以避免传统手术存在的语音和面部发育问题。方法８周龄杂种犬６只，腭骨内种置汞齐标记，用ＮｉＴｉＳＭＡ弓形牵张器前后方向牵张一侧腭横缝，维持８周。经临床，Ｘ线，干骨观察缝牵张后变化。结果４周时腭横缝牵张达到预定限度。Ｘ线片显示，牵张侧腭横缝前后两点汞齐标志的间距增加１５ｃｍ；前颌在牵张早期显著前突，随后逐渐回缩至两侧平齐。９个月头颅干骨发现，牵张侧腭骨后缘明显后移，上颌骨前移，鼻腭孔至硬腭后缘的距离较对侧增加４６～５９ｍｍ。结论腭横缝牵张可以造成永久性腭骨后退和上颌前移。

Hard palate lengthening by palatal suture expansion:an experimental study in dogs

Objective Scar contraction and lack of bony support for soft palate in traditional surgery of cleft palate are main causes of a shortening soft palate and its developmental deficiency.The wound and scar also lead to aberration of facial growth.In order to resolve these problems,lengthening of hard palate by transverse palatal suture expansion was studied. Methods Six mongrel dogs of 8week age were used in the study.Amalgam markers were implanted in the hard palate of the animal.A NiTishaped memory alloy (NiTiSMA) arch wire with a force level of 600g was used to expand the palatomaxillary suture with a retention period of 8 weeks.The dogs were killed at the age of 36 weeks.Serial Xray and cephalometry were used to investigate the changes. Results The suture expansion was generally completed in 4 weeks.The distance of separation of the palatine bone and maxilla was 10 to 15cm.Premaxilla became protrusive significantly at the beginning of the suture expansion,then restored gradually to its original position.The length of hard palate increased 4.6 to 5.9mm by dry skull measurement. ConclusionBZHard palate could be permanently lengthened anteriorposteriorly by transverse palatal suture expansion.