Department of Maxillofacial Surgery, University Institute of the Face and Neck, University Hospital of Nice, Nice, France.
Department of Orthodontics, University Hospital of Nice, Nice, France.
Am J Orthod Dentofacial Orthop. 2022 Sep;162(3):e133-e140. doi: 10.1016/j.ajodo.2022.01.012. Epub 2022 Jul 12.
The accurate mandibular condylar positioning for orthognathic surgical planning is fundamental in obtaining a planned occlusal result. The differences between the position of condyles seen on computed tomography or cone-beam computed tomography (CBCT) scans and during surgery reduce the accuracy of the result. This study aimed to assess the differences between the condylar position recorded on CBCT and a numerical 3-dimensional (3D) model created after mandibular repositioning for orthognathic surgery planning.
This study retrospectively evaluated 49 patients who underwent virtual orthognathic surgery planning. The procedure involved recording a computed tomography or CBCT of the skull and dental surface using an intraoral digital scanner. The mandible was repositioned on the numerical 3D model according to the superimposed virtual bite registration in centric relation. Linear and angular measurements of the right and left condyles were recorded before and after mandibular repositioning.
The positions of 98 condyles were compared. Linear measurements of the posterior and superior joint spaces revealed a significant difference. Subgroup analyses displayed statistically significant differences for patients with skeletal Class II malocclusion.
According to the digital bite registration method, the difference between the mandibular position recorded on CBCT and on the numerical 3D model after repositioning may have clinical significance. Further studies are needed to validate this theory and test the accuracy of the clinical results.
对于正颌手术规划来说,准确的下颌髁突定位对于获得预期的咬合结果至关重要。在计算机断层扫描(CT)或锥形束 CT(CBCT)扫描中看到的髁突位置与手术中看到的位置之间的差异降低了结果的准确性。本研究旨在评估在 CBCT 上记录的髁突位置与下颌重新定位后用于正颌手术规划的数值三维(3D)模型之间的差异。
本研究回顾性评估了 49 例接受虚拟正颌手术规划的患者。该过程涉及使用口腔内数字扫描仪记录颅骨和牙面的 CT 或 CBCT。根据在正中关系位上的虚拟咬合记录,将下颌重新定位在数值 3D 模型上。在重新定位下颌之前和之后,记录右侧和左侧髁突的线性和角度测量值。
比较了 98 个髁突的位置。关节后间隙和上间隙的线性测量显示出显著差异。亚组分析显示,对于骨骼 II 类错颌的患者,存在统计学上的显著差异。
根据数字咬合记录方法,CBCT 上记录的下颌位置与重新定位后的数值 3D 模型之间的差异可能具有临床意义。需要进一步的研究来验证这一理论并测试临床结果的准确性。