Development of a simulator for educational oral surgery using virtual reality

1996年和1997年，我们对正颌外科模拟器的基本问题进行了研究，开发了用于头颅正侧位片、CT和牙模型的侧位片的模拟程序。利用该程序，可以将X线头影测量所确定的坐标系应用于CT和牙模型测量数据，并在同一坐标系下观察这三个数据。1998年，我们尝试用AVS Medical viewer的图形工作站构建正颌外科手术模拟器，特别是下颌升支矢状劈开截骨术，并采用区域生长技术提取下颌骨。然后，利用松质骨的数据建立体素模型，使该模型能够应用于复杂的仿真。阈值被定义为200 Hounsfield单位。以前，截骨术可以在二维中模拟。在该系统中，可以在动作中模拟截骨，反映实际的外科手术，包括 关于我们 包括锯、钻和骨凿。的模块。因此，外科手术可以在三维计算机图形中模拟。三维计算机图形可以包含用于牙模型的数据，这使得在高精度地劈裂后自动移动侧骨碎片成为可能。此外，还开发了检测劈裂后两个骨碎片之间的干扰的功能，这使得能够分析以前难以预测的骨干扰，这澄清了这一点。骨性干扰会引起各种问题。在这个系统中，它需要大约。一个小时来模拟截骨，我们可以在改变截骨线后将该系统应用于其他外科手术。该系统具有高分辨率的三维图形和高可靠性的数据使用，具有较高的真实感，具有良好的教学模拟器功能。此外，该系统将有助于临床应用，包括诊断和治疗计划的研究。少

In 1996 and 1997, basic problems were studied for construction of a simulator for orthognathic surgery The programs of sulerimposition of the (lata for frontal and lateral cephalograms, CT and dental casts were developed. Using the programs, the coordinate system delineated by the cephalograms could be applied to the data for CT and dental casts, and these three data could be observed in the same coordinate system. Subsequently, construction of simulator for orthognathic surgery, especially sagittal split ramus osteotomy, was tried in 1998, using AVS Medical viewer of graphics workstation.Region growing technique was used for extraction of the mandible. A voxel model was then made with the data for cancellous bone, so this model could be applied to complex simulation. A threshold value was defined as 200 Hounsfield units. Formerly, osteotomy could be simulated in two-dimensions. In this system, osteotomy could be simulated in the maneuver that, reflected actual surgical procedures, inc … More luding saw, bur and osteotome after development. of modules. Consequently, surgical procedures could be simulated in three-dimensional computer graphics. Three-dimensional computer graphics could contain the data for dental casts, and this made it possible to automate shift of lateral bone fragments after splitting with high precision. Furthermore, function of detecting interference between two bone fragments after splitting was developed, and this enabled to analyze bony interference that it was formerly difficult to predict, and this clarified that. bony interference caused various problems.In this system, it. took about. an hour to simulate the osteotomy, and we can apply this system to other surgical procedures after altering osteotomy lines. This system possessed high reality because of three-dimensional graphics with high resolution and use of data with high reliability, and this system possessed satisfactory function of educational simulator. Furthermore, this system would be useful for clinical application including diagnosis and investigation of treatment plan. Less