Objectives: This clinical study aimed to evaluate the accuracy of a fully digital technique for measuring sagittal condylar inclination (SCI), as well as validating whether differences existed between the left and right SCI values of the same participant, to provide a reference for clinical practice.
Methods: Ten participants with good occlusal relationship and normal temporomandibular joint were recruited. Three methods were used to measure the SCI values of the participants, namely, A (mechanical facebow transferring and mechanical articulator-based measuring method with physical protrusive interocclusal registration), B (face scan-based virtual facebow and virtual articulator-based measuring method with digital protrusive interocclusal registration), and C (jaw motion tracking system-based measuring method). With the group subjected to methods A and C as the control, the SCI values obtained by the three methods were statistically analyzed. The left and right SCI values of the same participant were also compared.
Results: The left and right SCI values measured by method A were 41.70°±7.09° and 42.80°±8.62°, those by method B were 35.09°±12.49° and 37.63°±12.10°, and those by method C were 39.43°±8.72° and 38.45°±6.91°. No significant difference existed among the SCI values measured by the three methods (P>0.05). Meanwhile, no statistical difference existed between the SCI values on the left and right sides of the same participant (P>0.05).
Conclusions: The accuracy of the virtual facebow and digital protrusive occlusal registration based SCI measuring method was the same as that of mechanical facebow based and jaw motion tracking system-based methods. The SCI values on the left and right sides of the same participant were similar. Clinically, an appropriate SCI measurement and setting strategy can be selected based on the actual situations.
目的: 探究一种全数字化前伸髁导斜度（SCI）测量方法的准确性，同时对获取的受试者左、右侧SCI值进行对比分析，为临床实践提供参考。方法: 招募10名咬合关系良好、关节状态正常的受试者，分别使用方法A（传统机械面弓+基于实体牙合架的实体前伸咬合记录）、B（基于面部扫描数据构建的虚拟面弓+基于虚拟牙合架的数字化前伸咬合记录）、C（电子面弓描记）测量受试者左、右侧SCI值。以传统机械面弓+基于实体牙合架的实体前伸咬合记录组和电子面弓描记组作为对照组，基于面部扫描数据构建的虚拟面弓+基于虚拟牙合架的数字化前伸咬合记录组为实验组，对3种方法获得的左、右侧SCI值进行统计学分析，评估基于面部扫描数据构建的虚拟面弓+基于虚拟牙合架的数字化前伸咬合记录的全数字化方法用于SCI测量的准确性，同时分析同一受试者左、右侧SCI值之间差异是否存在统计学意义。结果: 方法A测量的左、右侧SCI值为41.70°±7.09°、42.80°±8.62°，方法B测量的左、右侧SCI值为35.09°±12.49°、37.63°±12.10°，方法C测量的左、右侧SCI值为39.43°±8.72°、38.45°±6.91°。3种方法测量的SCI值之间差异无统计学意义（P>0.05），同时同一受试者左、右侧SCI值之间差异也无统计学意义（P>0.05）。结论: 基于虚拟面弓和虚拟咬合记录的全数字化SCI测量方法的准确性与基于机械面弓和实体咬合记录法、电子面弓描记法无差异，同一受试者左、右侧SCI值类似，临床诊疗过程中可以根据实际选择合适的SCI测量和设置策略。.
Keywords: face scan; jaw motion tracking system; sagittal condylar inclination; virtual articulator; virtual facebow.