Schenz Natalie, Schwarz Vincent, Hörmann Romed, Crismani Adriano G
University Hospital for Orthodontics, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria.
Department of Cranio-Maxillofacial Surgery, Faculty of Medicine of the Kepler University Linz, Krankenhausstraße 9, 4020, Linz, Austria.
J Orofac Orthop. 2020 Nov;81(6):427-439. doi: 10.1007/s00056-020-00245-3. Epub 2020 Sep 8.
This study investigates the accuracy of abutment transfer with current impression materials and provides a concise overview, including other relevant factors, in order to enable clinicians to make an informed decision about the optimal impression for this treatment procedure.
In all, 96 impressions of a cadaver head with two orthodontic miniscrews in place were taken with four common impression materials by two observers and using two methods of application. After pouring with a standard type IV stone and abutment transfer, all models and the upper jaw (which had been separated from the head) were scanned in a standard model scanner (Zirkonzahn® [Zirkohnzahn GmbH, Gais, Italy] S600 ARTI) and evaluated using a computer-aided design (CAD) program (GOM-Inspect [Gesellschaft für optische Messtechnik m.b.H., Braunschweig, Germany]). The deviations were measured at six points per screw and statistically evaluated with SPSS® (IBM, Chicago, IL, USA).
Optimal values were obtained with biphasic polyvinylsiloxane, while monophasic polyvinylsiloxane, alginate and polyether also resulted in acceptable accuracy. Observer experience showed no effect and the method of application had only a minor effect on accuracy.
Within the limitations of this study, it seems that all impression materials are suitable for miniscrew abutment transfer, provided that methods of intraoral adaptation of the orthodontic appliance can be employed. If higher accuracy is needed or for clinicians with less experienced, a biphasic polyvinylsiloxane impression with the putty-wash technique should be used as this combination reduces setting time. The most cost-effective version, alginate, can be used if the consequences of greater deviations can be handled. Caution is advised with polyether if undercuts are present.
本研究调查了使用当前印模材料进行基台转移的准确性，并提供了一个简要概述，包括其他相关因素，以便临床医生能够就该治疗程序的最佳印模做出明智的决定。
两名观察者使用四种常见印模材料并采用两种应用方法，对一具已植入两颗正畸微螺钉的尸体头部进行了总共96次印模制取。用标准IV型石膏灌注并进行基台转移后，所有模型和上颌骨（已从头部分离）在标准模型扫描仪（Zirkonzahn® [Zirkohnzahn GmbH，盖斯，意大利] S600 ARTI）中进行扫描，并使用计算机辅助设计（CAD）程序（GOM-Inspect [Gesellschaft für optische Messtechnik m.b.H.，不伦瑞克，德国]）进行评估。在每个螺钉的六个点测量偏差，并使用SPSS®（IBM，伊利诺伊州芝加哥，美国）进行统计学评估。
双相聚硅氧烷获得了最佳值，而单相聚硅氧烷、藻酸盐和聚醚也产生了可接受的准确性。观察者经验没有影响，应用方法对准确性只有轻微影响。
在本研究的局限性内，似乎所有印模材料都适用于微螺钉基台转移，前提是可以采用正畸矫治器的口内适配方法。如果需要更高的准确性或对于经验较少的临床医生，应使用采用油泥-清洗技术的双相聚硅氧烷印模，因为这种组合减少了凝固时间。如果能够处理较大偏差的后果，可以使用最具成本效益的藻酸盐。如果存在倒凹，使用聚醚时需谨慎。
