Department of Orthodontics, University Hospital of RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Department of Oral and Maxillofacial Surgery, University Hospital of RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Clin Oral Investig. 2019 Dec;23(12):4425-4431. doi: 10.1007/s00784-019-02885-1. Epub 2019 Apr 13.
The aim of this cadaveric study was to measure the transfer accuracy of orthodontic mini-implant placement at the anterior palate depending on tooth-borne or gingiva-borne guide support.
Forty orthodontic mini-implants were placed paramedian in the anterior palate of 20 cadaver heads using tooth-borne (TBG) or gingiva-borne guides (GBG). Placement was planned after superimposition of lateral cephalograms and corresponding plaster models. After mini-implant placement, digital impressions were taken with scanbodies. For the measurement of both linear and angle deviations, virtual planning models and postoperative oral scans were compared using automatic surface registration based on an iterative closest point algorithm.
Statistical differences between TBG and GBG were detected for lateral deviations 0.88 mm (SD 0.46) versus 1.65 mm (SD 1.03) (p = .004) and sagittal angular deviations 3.67° (SD 2.25) versus 6.46° (SD 5.5) (p = .043). No differences were found for vertical deviations 2.34 mm (SD 0.74) versus 2.14 mm (SD 0.73) (p = .40) and transverse angular deviations 3.60° (SD 2.89) versus 4.06° (SD 3.04) (p = .62).
The use of surgical guides based on silicone provides sufficient control of orthodontic mini-implant placement and is comparable to CAD/CAM templates. However, when compared with guided dental implantology, the planned mini-implant position is more inaccurate. However, accuracy can be significantly increased by guide extension involving the teeth. Clinical investigations have to prove if the accuracy is sufficient for receiving an orthodontic appliance.
The use of lateral cephalograms and plaster models for silicone guide construction leads to lower radiation exposure and provides sufficient accuracy for palatal orthodontic mini-implant placement.
本尸体研究的目的是测量在前 palate 区根据牙支持或牙龈支持的引导器来转移正畸迷你种植体放置的准确性。
在 20 个尸体头颅的前 palate 区使用牙支持（TBG）或牙龈支持引导器（GBG）放置 40 个正畸迷你种植体。放置是在侧颅面照片和相应的石膏模型叠加后进行的。迷你种植体放置后，使用扫描体进行数字印模。为了测量线性和角度偏差，使用基于迭代最近点算法的自动表面配准来比较虚拟规划模型和术后口腔扫描。
在侧向偏差 0.88 毫米（SD 0.46）与 1.65 毫米（SD 1.03）（p =.004）和矢状角偏差 3.67°（SD 2.25）与 6.46°（SD 5.5）（p =.043）之间，TBG 和 GBG 之间存在统计学差异。在垂直偏差 2.34 毫米（SD 0.74）与 2.14 毫米（SD 0.73）（p =.40）和横向角偏差 3.60°（SD 2.89）与 4.06°（SD 3.04）（p =.62）之间未发现差异。
基于硅橡胶的手术导板可提供对正畸迷你种植体放置的足够控制，与 CAD/CAM 模板相当。然而，与引导式牙种植学相比，计划的迷你种植体位置更不准确。然而，通过涉及牙齿的导板延伸，可以显著提高准确性。临床研究必须证明这种准确性是否足以接收正畸器械。
使用侧颅面照片和石膏模型制作硅橡胶导板可减少辐射暴露，并为前 palate 区正畸迷你种植体放置提供足够的准确性。
