【摘要】 目的探讨对外置式牵引成骨技术矫治重度上颌后缩术后的长期稳定性。方法对采用外置式牵引器矫治的5例重度上颌发育不足患者拍摄治疗前、稳定期末、术后1年及术后3～6年头颅定位侧位片,分析其X线头影测量结果。结果SNA角术后一年平均复发率23.7%,术后3～6年平均复发率38.0%。A点水平位移术后一年内平均复发率27.6%,术后3～6年平均复发率39.0%。A点垂直位移在术后1年内或上升或下降,但术后1年到术后3～6年内该变量均为向下增长。结论①在外置式牵引器拆除后一年内存在明显复发倾向,一年后复发趋势仍然存在,但明显减弱。②牵引成骨术后上颌骨前部骨质存在不同程度吸收改建。③未成年患者采用外置式牵引成骨术后面中部在垂直方向上存在进一步生长发育的可能。更多还原

【Abstract】 Objective To discuss the long-term stability of maxillary distraction with rigid external distractor(RED).Methods Lateral cephalometry of 5 maxillary hypoplasia patients corrected by RED was done in different period,including pre-operation,when distractors were removed,1 year after distraction osteogenesis(DO),and 3～6 years after DO.Six factors were evaluated in the lateral cephalograms as follows:angle SNA,PP/FP,x and y values of point A and point PNS.The line SN was used as the x-axis and its perpendicular line through the sella was used as the y-axis.Results There was relapse in all patients one year after the distraction:angle SNA:23.7%,A(x):27.6%.After 3～6 years,the relapse was different:angle SNA:38.0%,A(x):39.0%.The point A moved downward for 1mm～6mm(mean,2.5mm)from 1 to 3～6 years after DO.Conclusion ①All patients had relapse in different degrees,and it mainly occurred during the first year after DO.In the following period,the relapse tendency was going on but slowed down.②In the anterior part of the maxilla,the bone could be absorbed and reconstructed after the DO.That was mainly happened during the first year.③The middle facial might have the ability to grow after DO.更多还原