目的

探讨结合计算机辅助设计（CAD）技术和快速成型（RP）技术制作个体化模板在口内进路下颌升支垂直截骨术中的准确性。

方法

选择湿性头颅4 例（8 侧）三维螺旋CT 扫描及三维重建，通过CAD 技术设计和RP 技术制作个体化模板，检测模板在升支的位置及适合性并按照模板边缘进行截骨，检测断面的位置；将这种方法应用于临床病例4 例，观察其有效性。

结果

个体化模板在湿头颅下颌升支完全就位，与骨表面紧密贴合无间隙；截骨位置与CAD 设计一致，未伤及下齿槽神经血管束，近心骨段宽度足够；临床应用模板引导截骨操作时间短、出血少，术后CT 检查截骨线与术前设计一致。

结论

个体化模板具有高度的准确性和良好的适合性，可以准确定位下颌升支垂直截骨线，并能稳妥方便地引导截骨。

Objectives

This study was designed to evaluate the accuracy of a CT-based osteotomy template on cadaver mandibles and to assess the outcome after intraoral vertical ramus osteotomy for correction of mandibular prognathism.

Methods

4 human cadaver heads were scanned by a high resolution multislice spiral CT. Raw CT data were processed with Mimics 12.0 and Magic RP Software in which osteotomy cuts were simulated. The files containing the osteotomy planning were sent to rapid prototyping center and Osteotomy templates were produced by stereolithography.

Results

A stable and secure fit of the stereolithographic templates on cadaver mandibles was achieved. Via the individual CT-based osteotomy template， the osteotomy lines were performed exactly as planed in the virtual osteotomies planning program. There were no damages to the maxillary artery and the inferior alveolar nerve， fracture of the proximal segment was not found.Similar favourite outcome was also observed in the clinic.

Conclusions

Use of the CT-based osteotomy templates is a safe method for osteotomy. It is rather convenient for vertical osteotomy in IVRO correcting mandibular prognathism，increasing the intraoperative accuracy and efficiency.