Kingrungpetch Supak, Aunmeungtong Weerapan, Khongkhunthian Pathawee
Center of Excellence for Dental Implantology, Faculty of Dentistry, Chiang Mai University, Chiang Mai, 50200, Thailand.
BMC Oral Health. 2024 Dec 2;24(1):1459. doi: 10.1186/s12903-024-05132-6.
To establish the occlusal plane, the conventional methods for facial analysis to gain accurate alignment of the occlusal plane are inadequate, while 3D technologies are an ideal diagnostic tool. The aims of this research are to compare the difference accuracy of anatomic landmarks on the occlusal plane and ala-tragus line between the conventional clinical method and 3D image method in both non-orthodontic and orthodontic treatment volunteers.
A total of 44 volunteers (22 non-orthodontic and 22 orthodontic treatment volunteers) with normal occlusion were selected. All volunteers received 2 operative methods for occlusal plane determination. In conventional method, the occlusal plane was defined by the fox plane line. The ala-tragus line was defined by the radio-opaque markers. In the 3D image method, the volunteers were recorded intraoral images, 3D facial images and CBCT images. A 3D virtual picture was created using EXOCAD® software. The occlusal plane was generated by the incisal and occlusal surfaces of the teeth. Both methods, the angles and distances between the occlusal plane and ala-tragus line were measured and compared statistically on both sides of each volunteer.
Both volunteers' group, the mean angles and distances between the occlusal plane-ala tragus line in the conventional method were reported to be significantly greater than the 3D method (P < 0.05). The percentage difference of angles in conventional method were reported to be significantly higher by 13.61-21.58% (p < 0.05) compared to the 3D method. The percentage difference of distances in the conventional method were reported to be significantly greater than the 3D method by 4.73-7.51% (p < 0.05).
Within the limitation of the study, it can be concluded that both conventional and digital methods for establishing the occlusal plane are not parallel to the occlusal plane. The occlusal plane and ala-tragus line in the conventional method and the 3D method were significantly different in terms of angles and distances in both non-orthodontic and orthodontic treatment volunteers. However, the deviation angle of both methods is approximately 13-20 degrees, which is clinically acceptable for occlusal plane establishment. The accuracy of both methods is still within the using in clinical implementation.
为确定咬合平面，传统的面部分析方法难以实现咬合平面的精确对齐，而三维技术是一种理想的诊断工具。本研究旨在比较常规临床方法与三维图像方法在非正畸和正畸治疗志愿者中，咬合平面和鼻翼 - 耳屏线解剖标志点的差异精度。
共选取44名咬合正常的志愿者（22名非正畸志愿者和22名正畸治疗志愿者）。所有志愿者均接受两种确定咬合平面的操作方法。在传统方法中，咬合平面由Fox平面线定义，鼻翼 - 耳屏线由不透射线标记物定义。在三维图像方法中，记录志愿者的口腔内图像、三维面部图像和锥形束CT（CBCT）图像。使用EXOCAD®软件创建三维虚拟图像，咬合平面由牙齿的切端和咬合面生成。对两种方法测量的每位志愿者两侧咬合平面与鼻翼 - 耳屏线之间的角度和距离进行统计比较。
在两个志愿者组中，传统方法中咬合平面 - 鼻翼耳屏线的平均角度和距离均显著大于三维方法（P < 0.05）。与三维方法相比，传统方法中角度的百分比差异显著高出13.61 - 21.58%（p < 0.05）。传统方法中距离的百分比差异比三维方法显著大4.73 - 7.51%（p < 0.05）。
在本研究的局限性内，可以得出结论，传统和数字方法确定的咬合平面均不与实际咬合平面平行。在非正畸和正畸治疗志愿者中，传统方法和三维方法在咬合平面与鼻翼 - 耳屏线的角度和距离方面存在显著差异。然而，两种方法的偏差角度约为13 - 20度，在临床上用于确定咬合平面是可接受的。两种方法的精度仍可用于临床实践。
