Apinhasmit Wandee, Methathrathip Dolly, Ploytubtim Sirilak, Chompoopong Supin, Ariyawatkul Thanase, Lertsirithong Anuchit
Department of Anatomy, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand.
J Med Assoc Thai. 2004 Oct;87(10):1212-7.
The maxillary artery (MA) and its terminal branches are commonly damaged in the maxillary osteotomy, especially during separation of the pterygomaxillary junction (PMJ).
To evaluate the positional relationship between the MA at the pterygomaxillary fissure (PMF) and the PMJ in Thais, as well as to measure the diameter of the MA as it enters the pterygopalatine fossa (PPF) and the heights of PMJ, maxillary tuberosity and posterior maxilla.
Both sides of 100 Thai adult cadavers (50 males and 50 females) were examined The mean age of the subjects was 64.5 +/- 12.8 years. With the lateral infratemporal approach, the branches from the third part of the MA, PMJ and posterolateral maxilla were dissected. Measurements taken included the following: First, the distance from the most inferior point of the PMJ to the most inferior position of the MA as it entered the PPF; second, the external diameter of the MA as it entered the PPF; third, vertical heights of the PMJ, maxillary tuberosity and posterior maxilla. Means, standard deviations and ranges were determined and statistical differences were calculated between sides and genders at p < 0. 05.
The MA entered the PPF at a mean distance of 23.5 +/- 2.5 mm above the most inferior point of the PMJ. The mean external diameter of the MA as it entered the PPF was 2.8 +/- 0.6 mm. The mean heights of the PMJ, maxillary tuberosity and posterior maxilla were 19.5 +/- 2.3 mm, 6.1 +/- 2.7 mm, and 25.6 +/- 3.3 mm, respectively. There were no differences with respect to side and gender, except that the distance from the most inferior point of the PMJ to the most inferior position of the MA as it entered the PPF was longer in males than in females (p < 0.05).
The mean location of the MA was 23.5 mm apart from the most inferior point of the PMJ, therefore, dysjunction of the PMJ using an osteotome with a 15-mm cutting edge may be conducted without damaging to the MA. When properly placed, the margin of safety from the superior cutting edge of the osteotome to the MA is approximately 8 mm in adults.
上颌骨截骨术中上颌动脉（MA）及其终末分支常易受损，尤其是在翼上颌连接处（PMJ）分离时。
评估泰国人翼上颌裂（PMF）处的MA与PMJ之间的位置关系，以及测量MA进入翼腭窝（PPF）处的直径和PMJ、上颌结节及上颌后部的高度。
对100具泰国成年尸体（50例男性和50例女性）的双侧进行检查。受试者的平均年龄为64.5±12.8岁。采用外侧颞下途径，解剖MA第三段的分支、PMJ和上颌后外侧部。测量项目包括：第一，PMJ最下点至MA进入PPF处最下位置的距离；第二，MA进入PPF处的外径；第三，PMJ、上颌结节及上颌后部的垂直高度。确定均值、标准差和范围，并计算p<0.05时两侧和两性之间的统计学差异。
MA进入PPF处位于PMJ最下点上方平均23.5±2.5mm处。MA进入PPF处的平均外径为2.8±0.6mm。PMJ、上颌结节及上颌后部的平均高度分别为19.5±2.3mm、6.1±2.7mm和25.6±3.3mm。除PMJ最下点至MA进入PPF处最下位置的距离男性长于女性（p<0.05）外，两侧和两性之间无差异。
MA的平均位置距PMJ最下点23.5mm，因此，使用刃长15mm的骨凿分离PMJ时可能不会损伤MA。放置合适时，骨凿上缘至MA的安全 margin 在成年人中约为8mm。
