不同方法制作正颌手术数字化[牙合]板的研究及精确性分析

目的探讨不同方法制作正颌手术数字化[牙合]板的流程,并评估其精确性及临床应用价值。方法选择2017年6月—2019年2月就诊于昆明医科大学附属口腔医院口腔颌面外科的牙颌面畸形患者10例为研究对象。分别利用单个软件和多个软件进行术前模拟设计,虚拟截骨,设计数字化[牙合]板,并评估二者精确性和工作时间。同时传统模型外科制作传统[牙合]板,评估单软件数字化[牙合]板的临床运用价值。结果单软件数字化[牙合]板最大拟合误差平均值上颌为(0.0111±0.0038)mm,下颌为(0.0107±0.0037)mm。单软件数字化[牙合]板最大拟合误差优于多软件数字化[牙合]板(P<0.001),各自上下颌面间差异无统计学意义(P>0.05)。[牙合]板术中未出现无法就位情况。无论是单颌还是双颌手术,单软件手术模拟时间均少于多软件手术模拟时间。结论不同方法制作数字化[牙合]板精确性存在差异,单软件数字化[牙合]板精确性优于多软件数字化[牙合]板,模拟耗时更少,具有实际应用价值。     

快速原型技术及石膏模型外科技术在下颌骨不对称畸形中的应用及效果评价

目的 探讨快速原型(rapid prototyping, RP)技术制作的高仿三维头颅模型与精确制取的牙弓石膏模型在面弓介导下精确结合,进行模型外科,用于指导下颌骨不对称畸形患者正颌手术的可行性,并评价其应用效果。方法 15例下颌骨不对称畸形、需要正颌手术的患者均进行全头颅三维螺旋CT扫描,将数据输入快速原型机,制作三维头颅模型,然后将牙弓石膏模型按等比例替换三维头颅模型的牙弓,以组成RP-石膏模型复合体;利用RP-石膏模型复合体进行术前模拟截骨,评价截骨位置及截骨量,评估患者颏部的对称性以及颞下颌关节的改变情况,术后6个月评估手术效果。结果 15例患者术前建立RP-石膏模型复合体,很好地预测了手术效果;2例发现经双侧下颌骨矢状劈开截骨术（BSSRO）后,颏部仍有偏斜,增加颏成形术。术后半年随访,患者对外形感到满意,无颞下颌关节紊乱综合征(TMJ)等并发症。结论 RP-石膏模型复合体可精确模拟截骨,对患者术后颏部及TMJ的改变,正颌手术的效果及可能出现的问题都具有重要指导价值。     

数字化导板在正颌外科的应用进展

正颌外科是通过外科手术与口腔正畸联合治疗,由于先天的生长发育异常或者后天的外伤等引起的单纯正畸不能解决的牙颌面畸形。颌面部血供丰富,解剖结构复杂,正颌手术术中常发生出血多、神经血管损伤、牙根损伤等各种并发症。为了降低这些并发症的发生率,以及使术后颌骨达到精确稳定的理想位置,正颌手术需使用各类导板[1]来辅助手术。传统导板制作流程复杂、误差大、耗时多。近年来,随着计算机辅助外科技术(CAS)的发展,运用数字化技术可以打印出不同的导板。数字化导板因拥有高精确性,能显著缩短手术时间,具有传统导板无法比拟的优点,目前被广泛应用到正颌外科手术中。本文就近年来数字化导板在正颌外科中的应用作一综述。     

数字化模型外科在牙颌面畸形治疗中的应用

目的 ：探讨数字化模型外科在牙颌面畸形治疗中的应用价值。方法 ：选取15例牙颌面畸形患者,通过CT重建模型与激光扫描牙列模型,构建数字化颅颌面-牙列模型,在此基础上进行手术设计,并且三维打印板及导板,指导手术。术后3个月进行面部对称性及手术精确度评价。结果 ：所有患者均顺利完成手术虚拟设计、板和导板三维打印以及正颌手术。偏颌畸形患者术后对称性明显改善,术后CT模型与术前设计比较,最大差异度<2 mm。结论 ：利用数字化模型外科可进行手术设计,模拟,预测,并且可以三维打印板及导板指导手术,在牙颌面畸形的治疗中具有广泛的应用价值,值得临床推广。     

不同方法制作正颌手术数字化板的研究及精确性分析

目的 探讨不同方法制作正颌手术数字化板的流程,并评估其精确性及临床应用价值.方法 选择2017年6月—2019年2月就诊于昆明医科大学附属口腔医院口腔颌面外科的牙颌面畸形患者10例为研究对象.分别利用单个软件和多个软件进行术前模拟设计,虚拟截骨,设计数字化板,并评估二者精确性和工作时间.同时传统模型外科制作传统板,评估...     

计算机辅助正颌外科的研究现状

计算机与医学影像技术的快速发展加速了生物医学工程的发展,计算机辅助正颌外科也成为了目前的研究热点。计算机技术贯穿至术前资料的采集与分析、手术计划、手术效果预测和虚拟手术的现实转移整个过程中,具有传统方法无法比拟的优点,是今后正颌外科的发展方向。本文将围绕以上各环节的研究进展作一综述。     

新技术在当代牙颌面畸形矫治中的开发与应用

<正>1牙颌面畸形外科治疗的历史牙颌面畸形(dento-maxillofacial deformities)系指因颌骨发育异常引起的颌骨的体积、形态以及上下颌骨之间及其与颅面其他骨骼之间的关系异常,     

双板在双颌正颌外科中的应用

目的　总结双牙合板在双颌正颌外科中的作用。方法　在对６８ 例上颌前突、双颌前突、骨性开牙合及双颌后缩等颌面部畸形患者施行双颌正颌手术中,利用双牙合板的引导作用,使上下颌骨骨段准确移动达到术前设计的位置,同时辅以微型钛夹板坚固内固定。结果　术后随访６ 个月～７ 年,效果良好,面部外形及咬合关系明显改善且稳定。结论　双牙合板的应用可实现颌骨在三维空间的定量化移动并保持上下牙弓的咬合关系,提高了手术的精确度。     

双He板技术在正颌外科中的应用

模型外科是现代正颌外科治疗方案设计中必不可少的一项特殊技术＾〔１,２〕。通过临床检查及头影测量分析确定患者牙－颌－面畸形的情况,上、下凳骨需移动的方向及数量,初步决定颌骨需整体抑或分段移动,以便选择适当手术方式。手术中确切的截骨部位、去骨量与去骨形态、牙－骨段移动的具体方位以及良好Ｈｅ关系的拼对,均需依靠模型外科取得。在完成模型外科后的石膏模型上做Ｈｅ板（终末Ｈｅ板）,记录牙－骨段的移动方位。手术中以此Ｈｅ板引导牙－骨段的移动,以实现设计目标。     

An integrated orthognathic surgery system for virtual planning and image-guided transfer without intermediate splint

Accurate surgical planning and transfer of the planning in orthognathic surgery are very important in achieving a successful surgical outcome with appropriate improvement. Conventionally, the paper surgery is performed based on a 2D cephalometric radiograph, and the results are expressed using cast models and an articulator. We developed an integrated orthognathic surgery system with 3D virtual planning and image-guided transfer. The maxillary surgery of orthognathic patients was planned virtually, and the planning results were transferred to the cast model by image guidance. During virtual planning, the displacement of the reference points was confirmed by the displacement from conventional paper surgery at each procedure. The results of virtual surgery were transferred to the physical cast models directly through image guidance. The root mean square (RMS) difference between virtual surgery and conventional model surgery was 0.75 ± 0.51 mm for 12 patients. The RMS difference between virtual surgery and image-guidance results was 0.78 ± 0.52 mm, which showed no significant difference from the difference of conventional model surgery. The image-guided orthognathic surgery system integrated with virtual planning will replace physical model surgical planning and enable transfer of the virtual planning directly without the need for an intermediate splint.     

A novel method of computer aided orthognathic surgery using individual CAD/CAM templates: a combination of osteotomy and repositioning guides

The maxilla is usually positioned during orthognathic surgery using surgical splints, which has many limitations. In this preliminary study we present a new computer-aided design and manufacture (CAD/CAM) template to guide the osteotomy and the repositioning, and illustrate its feasibility and validity. Six patients with dental maxillofacial deformities were studied. The design of the templates was based on three-dimensional surgical planning, including the Le Fort osteotomy and the repositioning of the maxilla, and were made using a three-dimensional printing technique. Two parts of the templates, respectively, guided the osteotomy and repositioned the maxilla during operation. The traditional occlusal splint was used to achieve the final occlusion with the mandible in the expected position. Postoperative measurements were made between maxillary hard tissue landmarks, relative to reference planes based on computed tomographic (CT) data. The results of the measurements were analysed and compared with the virtual plan. The preliminary results showed that we achieved clinically acceptable precision for the position of the maxilla (<1.0 mm). Preoperative preparation time was reduced to about 145 min. All patients were satisfied with the aesthetic results. Our CAD/CAM templates provide a reliable method for transfer of maxillary surgical planning, which may be a useful alternative to the intermediate splint technique. Our technique does not require traditional model surgery, scanning of dental casts, or recording of the CAD/CAM splint.     

Accuracy of splint vs splintless technique for virtually planned orthognathic surgery: A voxel-based three-dimensional analysis

PurposeThis study compared two transferring methods for virtually planned orthognathic surgery — the CAD/CAM intermediate splint and the customized surgical guide with fixation plates.MethodsThis was a prospective clinical study in which participants were consecutively recruited and underwent bimaxillary orthognathic surgery. They were divided into two groups based on the transferring method used. The pre- and postoperative CBCTs were aligned using voxel-based landmark-free registration, and the discrepancies for selected points were compared with the planned displacement of the virtually planned surgery. The maxilla and mandible were analyzed separately, and translation and rotation movements were considered.ResultsA total of 16 patients, divided into two groups of eight patients each, were included in this study. The splintless group was significantly more accurate for the translation movement along the x-axes for points A (p = 0.008; mean absolute error 0.527 ± 0.387 for the splint group and 0.137 ± 0.067 for the splintless group) and Ans (p = 0.045; mean absolute error 0.535 ± 0.446 for the splint group and 0.156 ± 0.002 for the splintless group). For the mandible there was a significant difference in accuracy along the x-axes for points B (p = 0.049; mean absolute errors 1.728 ± 1.181 and 0.697 ± 0.519 for the splint and splintless groups, respectively), LL3 (p = 0.049; mean absolute error 1.629 ± 0.912 and 0.851 ± 0.797 for the splint and splintless groups, respectively), LR3 (p = 0.049; mean absolute error 1.711 ± 0.906 and 0.844 ± 0.780 for the splint and splintless groups, respectively), with the splintless group being more accurate. For the rotation the splintless group was significantly more accurate along the y-axes (p = 0.04; mean absolute error 1.62 ± 0.78 and 0.49 ± 0.31 for the splint and splintless groups, respectively) and z-axes (p = 0.04; mean absolute error 0.63 ± 0.45 and 0.17 ± 0.05 for the splint and splintless groups, respectively) for the maxilla, while no significant difference was found for the mandible.ConclusionsOverall, the customized fixation plate system is more accurate than the intermediate CAD/CAM splint for transferring the virtual plan into the operation room.     

正颌外科术后患者的满意度调查

本文通过问卷回顾性地调查了126位正颌外科术后1年以上患者的满意度。93．6%的患者对手术后容貌的改变满意;849%的患者愿意向有类似畸形的亲朋好友推荐正颌外科手术;74.8％的患者愿意再选择手术;64.3％以上的患者术后感觉自信心提高,与他人交往更自如,幸福感增强。     

正颌外科矫正牙颌面畸形300例总结

目的为总结正颌外科矫正牙颌面畸形的临床经验,方法对300例牙颌面畸形患者进行了正颌外科手术,其中180例上颌前突和上颌前部发育不足畸形,行上下颌前部根尖下戴骨术;40例上下颌后牙正反锁,行节段性根尖下戴骨术。80例下颌前突畸形分别采用了SSRO、IVRO、SOM等戴骨术结果300例牙颌面畸形术后外观及功能绝大多数获得了满意的效果。其中术后复发11例,明显复发2例;感觉异常4例;术后感染10例。结论随访结果显示应用AMO,SSRO,IVRO,SOM法矫正牙颌面畸形,获得了满意的效果,并能减少复发,感染和局部感觉异常的发病率。文中就此类手术的术前后正畸、手术方法、手术中注意事项等进行了讨论.     

Consent for orthognathic surgery: a UK perspective

Obtaining consent to undertake orthognathic surgery is a legal requirement that starts at the initial visit when treatment is being considered and continues until the operation itself. The process includes discussion of the benefits, risks, and potential complications of the proposed procedure, and any alternative (including doing nothing), but there is no consensus about how much information should be disclosed. Guidance is provided on the basis of case law, which is itself evolving. The purpose of this study was to look at the current practice of obtaining consent for orthognathic surgery by oral and maxillofacial surgeons in the UK to act as a benchmark and potentially to stimulate further debate. We also review common and serious complications that might be included in the process.     

正颌外科治疗后颞下颌关节改变的X线研究

目的 了解正颌外科手术后颞下颌关节（ｔｅｍｐｏｒｏｍａｎｄｉｂｕｌａｒ ｊｏｉｎｔ,ＴＭＪ）形态的改变,探讨手术方式不同对ＴＭＪ的影响。方法 正颌手术患者５７例,术前、术后１周、１年分别拍摄定位许勒位片用于观察髁突位置及关节形态的变化。结果 ①正颌手术可导致髁突移位,但大多数关节适应后并不发生病变,术后１年髁突位置已调整到术前相似的位置。②手术方式不同髁突位置的变化也不尽相同。③８６．４％的患者关节无明显变化或发生了适应性改建;１３．６％患者关节发生了退行性改变。结论 正颌手术可对ＴＭＪ产生影响,但大部分处于关节的正常适应范围内。     

人工智能时代的正颌外科发展

简要回顾人工智能（AI）技术的概念及其在不同时代发展历程,概述AI在医疗领域的应用,回顾综述AI在正颌外科发展的研究进展、存在的问题及可能的发展方向,指出AI在正颌外科的发展充满机遇与挑战并存。     

The accuracy of two-dimensional planning for routine orthognathic surgery

Two-dimensional cephalometric planning software should be helpful for prediction of hard tissue outcome after bilateral sagittal split ramus osteotomy (BSSRO) or bimaxillary osteotomy, but transferring two-dimensional data to three-dimensions (including mock operation and surgery) may result in errors. The objective of this retrospective study was to analyze deviations between predicted results and postoperative outcome using cephalometric analyses, and to evaluate this procedure for daily use. Fifty-four subjects (mean (SD) age 26 (8) years) had a BSSRO (n = 21) alone or in combination with Le Fort I osteotomy (n = 33). Predictions were made for each case by cephalometric planning software and mock operations done with study models. Postoperative cephalograms were obtained after 14 days and compared with predicted cephalograms for sagittal (SNA, SNB, ANB,) and vertical (ArMeGo, ML–NSL, NL–NSL) measurements. Mean (SD) differences for all measurements varied between 1.3° (1.1°) and 2.2° (1.6°) for BSSRO; and between 1.1° (1.3°) and 2.2° (1.6°) for bimaxillary osteotomy. There were no significant differences between measurements or operations, indicating that the predictions were accurate. A difference of up to 8.5° could be measured in a single case. Cephalometric prediction therefore remains an accurate tool for planning, particularly maxillary rearrangement in the vertical and sagittal dimension for routine operations. If greater shifts in the transversal dimension are necessary, exact planning should be adapted with three-dimensional planning devices to avoid significant differences.