Le Fort I型截骨术定位平面的应用解剖学研究

目的：研究Le Fort I型截骨术与上颌牙根尖的关系，为临床合理制订截骨平面提供解剖学依据。方法：选择上颌牙槽清晰或出土后仍有牙保留的颅骨，在颅骨梨状孔下缘至上颌结节作一连线作为模拟Le Fort I型术式截骨水平，以上颌牙槽缘为标志，用游标卡尺测量每侧上颌各牙的牙槽缘至上述模拟截骨水平的距离及牙槽缘至各牙根尖端的长度，然后计算出上颌各牙根尖至Le Fort I型术式截骨线的距离。结果：上颌各牙相对的牙槽缘至Le FortI型术式截骨线的距离，从中切牙至第二磨牙逐渐缩小，右侧中切牙为21．09±1．53mm，左侧中切牙为20．96±1．64mm，右侧第二磨牙为14．94±1．52mm，左侧第二磨牙为14．95±1．59mm；上颌各牙根尖至Le Fort I型术式截骨水平的距离，从中切牙至第二磨牙也逐渐缩小，而两侧尖牙牙根尖距离Le Fort I型术式截骨线的距离右侧为4．49±1．74mm，左侧为4．69±2．14mm，第二磨牙牙根尖距离Le Fort I型术式截骨线的距离右侧为4．65±1．63mm，左侧为4．49±1．89，两侧尖牙牙根尖和第二磨牙牙根尖至Le Fort I型术式截骨水平的距离均比较接近。结论：上颌各牙根尖至LeFortI型术式截骨线的距离均在4mm以上，根据前牙中尖牙牙根尖的位置和后牙中第二磨牙牙根尖的位置，Le Fort I型术式截骨线水平在13、23（3｜3）根尖及27、27（7｜7）根尖上方4mm以上，按此平面作截骨水平较为安全，不易损伤牙根。

The Applied Anatomy Research of LeFort I Osteotomy Reference Plane

Objective： To study the relationship of apex dentis of upper jaw and LeFort I osteotomy, provides anatomy basis for reasonable clinical of osteotomy level. Method： Selecting the clear alveoli dentales maxillae or the skull of entire maxillary teeth after being excavated, make a line under the low marge of apertura piriformos to maxillary tuberosity as a stimulation of the Le Fort I osteotomy level, Take the alveoli dentales maxillae as the symbol, measure the above distance and the length between alveolar border and apex of root of tooth by vermier caliper. Then calculated the distance of dental tooth in upper jaw to Le Fort I osteotomy level. Result： From central incisor to the second molar, the distance of alveoli dentales maxillae to Le Fort I osteotomy gradually decline, right central incisor 21.09±1.53 mm, left central incisor 20.96± 1.64mm;right second molar14.94±1.52mm, left second molar14.95±1.59mm;the same also the distance of apex dentis of upper jaw to Le Fort I osteotomy, while the distance of both sides canine apex dentis to Le Fort I os- teotomy, the right 4.49±1.74ram, left 4.69±2.14mm, the distance of second molar of apex dentis to Le Fort I osteotomy in right is 4.65±1.63mm,left 4.49±1.89mm, From both sides canine apex dentis and the second molar apex dentis to Le Fort I osteotomy are more close. Coelusion： The distance of apex of root of tooth to Le Fort I osteotomy level are all above 4mm, according to the situation of front canine root apex and posterior second molar root apex, Le Fort I osteotomy level should under 13,23 （ 3 ｜ 3 ） and 17, 27 （ 7 ｜7 ） point above the 4mm, it is not easy to injure dental root.