Mahmood Trefa Mohammed Ali
Department of Pedodontics, Orthodontics and Preventive Dentistry, College of Dentistry, University of Sulaimani, Sulaimaniyah 46001, Iraq.
Diagnostics (Basel). 2023 Jul 18;13(14):2395. doi: 10.3390/diagnostics13142395.
With the introduction of high-tech appliances, anchorage devices, and improved patient awareness of the risks associated with maxillofacial surgery, treating complex situations with orthodontic treatment has become more difficult in recent years. This study was conducted to demonstrate that orienting the occlusal plane, all the dental, skeletal, and soft tissue parameters, would be improved and to find which of these parameters could be correlated with the steepness of the occlusal plane.
This was a retrospective study including 40 cephalometric interpretations for patients who were planned for four-unit extractions (20 cephalometric radiographies before treatment and 20 after finishing the treatment). All were treated in the same orthodontic clinic with the same protocol using the McLaughlin-Bennett-Trevisi (MBT) prescription, with 22 slots and one-step retraction following four-unit extraction based on temporary anchorage devices (TADs).
There was no significant change in the canting of the occlusal plane, and it remained relatively stable from 6.31° to 7.55°, while all the soft tissue-related cephalometric measurements were reduced significantly, except the nasolabial angle, as the relation of the upper and lower lip to the esthetic line of Ricketts' (E-Line) was reduced by 2.91 and 2.46°, respectively; furthermore, the angle of convexity was reduced from 10.92° to 9.79°. Besides, the upper incisor display was reduced by 0.38° Conclusions: Both the Frankfort mandibular angle and upper-incisor-to-Frankfort horizontal plane were significant parametric factors associated with profile change after extraction treatment having a positive 0.01-level Pearson association with occlusal plane steepness. Therefore, using the MBT prescription with TAD-based retraction is one of the favorable methods for the management of complex cases.
随着高科技设备、锚固装置的引入以及患者对颌面外科手术相关风险认识的提高，近年来使用正畸治疗处理复杂情况变得更加困难。本研究旨在证明调整咬合平面后，所有牙齿、骨骼和软组织参数都会得到改善，并找出哪些参数与咬合平面的倾斜度相关。
这是一项回顾性研究，包括对计划进行四颗牙齿拔除的患者的40张头影测量分析（治疗前20张头影X线片，治疗结束后20张）。所有患者均在同一正畸诊所按照相同方案进行治疗，采用麦克劳林-贝内特-特雷维西（MBT）矫治器，有22个托槽，并在基于临时锚固装置（TAD）的四颗牙齿拔除后进行一步内收。
咬合平面的倾斜度无显著变化，相对稳定在6.31°至7.55°，而所有与软组织相关的头影测量值均显著降低，但鼻唇角除外，因为上唇和下唇与里克茨审美线（E线）的关系分别降低了2.91°和2.46°；此外，凸度角从10.92°降至9.79°。此外，上前牙暴露度降低了0.38°。结论：法兰克福下颌角和上切牙至法兰克福水平面均是拔牙治疗后与侧貌变化相关的重要参数因素，与咬合平面倾斜度呈正相关，皮尔逊相关系数为0.01水平。因此，使用基于TAD内收的MBT矫治器是处理复杂病例的有利方法之一。
