Adolphs Nicolai, Liu Weichen, Keeve Erwin, Hoffmeister Bodo
Klinik für Mund-, Kiefer- und Gesichtschirurgie, Zentrum für rekonstruktive und plastisch-ästhetische Gesichtschirurgie, Charité Universitätsmedizin Berlin, Campus Virchow Klinikum , Berlin , and.
Comput Aided Surg. 2014;19(1-3):20-8. doi: 10.3109/10929088.2014.887778. Epub 2014 Apr 10.
Within the domain of craniomaxillofacial surgery, orthognathic surgery is a special field dedicated to the correction of dentofacial anomalies resulting from skeletal malocclusion. Generally, in such cases, an interdisciplinary orthodontic and surgical treatment approach is required. After initial orthodontic alignment of the dental arches, skeletal discrepancies of the jaws can be corrected by distinct surgical strategies and procedures in order to achieve correct occlusal relations, as well as facial balance and harmony within individualized treatment concepts. To transfer the preoperative surgical planning and reposition the mobilized dental arches with optimal occlusal relations, surgical splints are typically used. For this purpose, different strategies have been described which use one or more splints. Traditionally, these splints are manufactured by a dental technician based on patient-specific dental casts; however, computer-assisted technologies have gained increasing importance with respect to preoperative planning and its subsequent surgical transfer.
In a pilot study of 10 patients undergoing orthognathic corrections by a one-splint strategy, two final occlusal splints were produced for each patient and compared with respect to their clinical usability. One splint was manufactured in the traditional way by a dental technician according to the preoperative surgical planning. After performing a CBCT scan of the patient's dental casts, a second splint was designed virtually by an engineer and surgeon working together, according to the desired final occlusion. For this purpose, RapidSplint, a custom-made software platform, was used. After post-processing and conversion of the datasets into .stl files, the splints were fabricated by the PolyJet procedure using photo polymerization. During surgery, both splints were inserted after mobilization of the dental arches then compared with respect to their clinical usability according to the occlusal fitting.
Using the workflow described above, virtual splints could be designed and manufactured for all patients in this pilot study. Eight of 10 virtual splints could be used clinically to achieve and maintain final occlusion after orthognathic surgery. In two cases virtual splints were not usable due to insufficient occlusal fitting, and even two of the traditional splints were not clinically usable. In five patients where both types of splints were available, their occlusal fitting was assessed as being equivalent, and in one case the virtual splint showed even better occlusal fitting than the traditional splint. In one case where no traditional splint was available, the virtual splint proved to be helpful in achieving the final occlusion.
In this pilot study it was demonstrated that clinically usable splints for orthognathic surgery can be produced by computer-assisted technology. Virtual splint design was realized by RapidSplint®, an in-house software platform which might contribute in future to shorten preoperative workflows for the production of orthognathic surgical splints.
在颅颌面外科领域，正颌外科是一个专门用于矫正骨骼错牙合导致的牙颌面畸形的特殊领域。一般来说，在这类病例中，需要采用正畸和外科的跨学科治疗方法。在牙弓进行初步正畸排齐后，可通过不同的手术策略和程序来矫正颌骨的骨骼差异，以实现正确的咬合关系，以及在个性化治疗理念下达到面部平衡与和谐。为了转移术前手术计划并重新定位具有最佳咬合关系的活动牙弓，通常会使用外科夹板。为此，已经描述了使用一个或多个夹板的不同策略。传统上，这些夹板由牙科技师根据患者特定的牙模制作；然而，计算机辅助技术在术前规划及其后续手术转移方面变得越来越重要。
在一项对10例采用单夹板策略进行正颌矫正的患者的初步研究中，为每位患者制作了两个最终咬合夹板，并比较了它们的临床可用性。一个夹板由牙科技师按照术前手术计划以传统方式制作。在对患者牙模进行CBCT扫描后，由工程师和外科医生共同根据期望的最终咬合虚拟设计第二个夹板。为此，使用了定制软件平台RapidSplint。在对数据集进行后处理并转换为.stl文件后，通过光聚合的PolyJet程序制作夹板。在手术过程中，在活动牙弓后插入两个夹板，然后根据咬合贴合情况比较它们的临床可用性。
使用上述工作流程，在本初步研究中可以为所有患者设计和制造虚拟夹板。10个虚拟夹板中有8个可在临床上用于在正颌手术后实现并维持最终咬合。在两例中，由于咬合贴合不足，虚拟夹板无法使用，甚至两个传统夹板在临床上也无法使用。在5例两种类型夹板都可用的患者中，评估它们的咬合贴合度相当，在1例中虚拟夹板的咬合贴合度甚至优于传统夹板。在1例没有传统夹板的情况下，虚拟夹板被证明有助于实现最终咬合。
在本初步研究中表明，计算机辅助技术可以制作临床上可用的正颌外科夹板。虚拟夹板设计通过内部软件平台RapidSplint®实现，该平台未来可能有助于缩短正颌外科夹板制作的术前工作流程。
