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...     

计算机辅助模型外科设计及虚拟[牙合]板的临床应用

目的：通过计算机辅助软件进行正颌手术模型外科设计，经快速原型技术制作[牙合]板，探讨该[牙合]板的临床应用价值。方法：15例颌面畸形需要正颌手术的患者均进行全头颅三维CT扫描（层厚0．625mm），将DICOM格式的CT数据输入电脑软件Simplant CMF（Materialise Medical，Leuven，Belgium）。通过软件对头颅模型进行上下颌骨的分离、截骨线的设计、截骨、骨块移动等操作，收集并输出数据，经快速原型机制作[牙合]板（虚拟[牙合]板）。同时，每例患者还进行传统石膏模型外科以及传统[牙合]板制作。术中首先利用虚拟[牙合]板进行骨块的移动和固定，然后应用传统[牙合]板检验骨块的新位置，验证虚拟[牙合]板的临床实用性。结果：15例患者中．4例单颌手术（双侧下颌支矢状劈开术）、10例双颌手术（LeFortⅠ型整体截骨术＋双侧下颌支矢状劈开术）以及1例双颌手术（LeFortⅠ型分块截骨术＋双侧下颌支矢状劈开术）。手术中，12例患者的虚拟[牙合]板完全符合临床要求。3例患者（包括1例双侧下颌支矢状劈开术和2例LeFortⅠ型整体截骨术＋双侧下颌支矢状劈开术）的虚拟[牙合]板与传统[牙合]板之间有部分偏差，遂通过传统[牙合]板进行骨块的重新固定。结论：计算机辅助设计可完成LeFortⅠ型整体（或分块）截骨术和双侧下颌支矢状劈开术的模型外科，虚拟[牙合]板基本可实现传统[牙合]板的功能。通过对软件的进一步熟悉、更多病例的积累，计算机辅助模型外科可能取代传统的石膏模型外科。     

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。     

数字化咬合板与传统咬合板在正颌手术中定位上颌骨的精确性临床研究

目的:通过临床研究分析数字化咬合板与传统咬合板在正颌手术中定位上颌骨的精确性。方法:回顾性收集2017～2022年就诊于南京大学医学院附属口腔医院的成年骨性错(牙合)畸形患者,筛选具有完善术前术后影像学CT数据、牙列模型数据且已完成双颌正颌手术的病例18例,其中8例通过传统咬合板辅助正颌手术,10例通过数字化咬合板辅助正颌手术。根据患者术前术后影像学资料及牙列数据通过Mimics Research 20.0及3-matic Research 12.0软件完成颅骨模型重建以及牙列模型数据的替换,完成正颌手术术前、术后三维(冠状位,矢状位,轴位)方向上实际移动距离的测量。测量三维方向上术前预计移动距离与术后实际移动距离的线性差异。结果:传统咬合板组术前计划与术后实际移动平均线性差为(1.00±0.32)mm;数字化咬合板组术前计划与术后实际移动平均线性差为(0.99±0.38)mm。两种咬合板对指导正颌手术中上颌骨的三维方向的定位无显著差异。结论:数字化咬合板与传统咬合板的使用均可在正颌手术中准确定位上颌骨。     

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。     

数字化软件在牙颌面畸形正颌术前模拟设计中的应用研究

目的 通过数字化软件对牙颌面畸形患者进行正颌术前模拟设计,将得到的数据应用于临床手术中以指导术者对牙颌面畸形进行精确的手术治疗。方法 选择2012年1月至2013年1月到中国医科大学附属口腔医院口腔颌面外科就诊的牙颌面畸形患者15例,进行术前三维CT扫描,将CT数据输入proplan软件系统中。通过软件重建上下颌骨,在三维方向上对颌骨进行定点、截骨、移动骨段、模拟预测等操作,确定手术方案后保存数据。术中按照软件模拟方案进行手术。结果 15例患者手术顺利,术中未出现严重并发症。术后半年随访,满意率达到93.3%。结论 采用数字化软件对牙颌面畸形患者进行术前模拟设计是一种较为精确的方法,可直观模拟手术并预测术后效果,从而为正颌外科矫治复杂牙颌面畸形制定个体化最佳手术方案提供实用有效的技术和依据。     

基于配准技术的微创牙种植导向模板的制作方法及应用

目的设计制作精确的微创牙种植导向模板,以指导医生准确地手术定位。方法对行种植手术的患者下颌骨进行CT扫描,依据CT数据构建三维牙颌模型,并利用Simplant专业种植软件在三维模型的基础上进行模拟种植,确定种植体的位置和深度。对牙颌石膏模型进行数字化扫描,通过曲率配准技术将石膏模型和CT三维模型进行对齐,确定种植体设计位置与牙颌扫描模型的关系,根据种植体位置,在牙颌石膏数字化模型上利用3-Matic软件完成导向模板的设计,最后利用快速成型技术制作导向模板。结果通过配准技术将CT数据与牙颌数字化数据相融合,设计出的微创导板定位精确,在无需切开口腔黏膜的情况下依然能够很好地为医生在实际种植时提供导向。结论将三维配准技术应用于种植领域,结合Simplant模拟种植和快速成型等技术制作的微创种植导向模板定位准确,实现了手术的微创性与精确性,值得临床推广使用。     

数字化技术在牙颌面畸形治疗中的应用研究

目的    探讨数字化技术在牙颌面畸形治疗中的应用。 方法    选择2014年12月至2015年12月于中国医科大学附属口腔医院口腔颌面外科行正颌手术的牙颌面畸形患者12例,通过上下颌骨3D-CT重建DICOM数据,构建数字化头颅模型并3D打印头颅模型,进行手术前模拟设计,模拟截骨,指导手术。术后3个月进行面部对称性评价。结果    所选12例患者均完成手术模拟并3D打印头颅模型,最后进行正颌手术。术后3个月复查面部对称性改善明显。满意率达到91.67%。结论    利用数字化技术进行手术模拟设计,3D打印头颅模型模拟截骨,并指导手术,提高手术精确度,在牙颌面畸形的治疗中具有实际的应用价值。     

三维打印及功能引导路径技术获得诊断性全冠功能性[牙合]面形态初探

目的通过在三维打印诊断性全冠上运用功能引导路径(functional generated path,FGP)技术获得修复体功能性[牙合]面形态,探索减少修复体面调改量以及避免干扰的临床方法。方法选择2018年7月至2018年12月于北京大学口腔医学院·口腔医院修复科就诊、需行下颌第一磨牙全冠修复的患者10例,其中男性4例,女性6例,年龄(29.6±7.4)岁;进行基牙预备体模型扫描并获得数字化模型;分别为每例患者制作两种全冠修复体。试验组:制作三维打印聚乳酸基底冠和蜡面,通过口内FGP法直接获得具有功能接触形态的面,扫描后制作计算机辅助设计与辅助制作氧化锆全冠修复体;对照组:按照数据库及经验常规设计制作氧化锆全冠修复体。临床试戴后用逆向工程软件(Geomagic Sudio&Quality)对修复体[牙合]面调改前后的咬合接触位置及面积、咬合接触程度、面调改高度和体积等指标进行数字化定量分析,并对两组数据进行配对t检验。结果10例患者均顺利通过FGP法获得面形态。试验组修复体[牙合]面调改体积[(7.320±4.238)mm3]显著小于对照组[(20.178±9.650)mm3](P<0.05);调改前试验组咬合高点高度[(0.043±0.019)mm]显著低于对照组[(0.594±0.201)mm](P<0.05),咬合接触面积[(11.430±4.102)mm2]显著大于对照组[(4.808±3.223)mm2](P<0.05)。结论运用三维打印及功能引导路径技术可获得修复体[牙合]面的个性化功能接触形态,可比常规方法显著减少修复体[牙合]调改量并降低咬合高点。     

颅颌运动仿真系统(牙合)接触精度初探

目的 探讨颅颌运动仿真系统的骀接触模拟精度,为该仿真系统的应用提供依据.方法 制作10副石膏模型并上(牙合)架.用(牙合)架模拟侧方运动,三维扫描侧方运动终点(牙合)架上的上下颌模型,重建数字化上下颌模型作为对照组.运用仿真系统模拟耠架的侧方运动,以仿真系统输出的侧方运动终点的数字化上下颌模型为试验组.通过比较试验组与对照组下颌牙列之间的位置差异评价仿真系统的(牙合)接触模拟精度.结果 仿真系统模拟的下颌牙列与对照组下颌牙列之间的绝对平均距离为(0.18±0.05)mm;在前后左右四个分区中,两组右后牙区之间的绝对平均距离最大,为(0.19±0.07)mm.结论 该仿真系统的体外胎接触模拟精度为0.19mm.     

咬合板高度对TMD患者咀嚼肌肌电的影响

目的:研究不同高度的咬合板对颞下颌关节紊乱病(TMD)患者颞肌前束、咬肌肌电的影响。方法:73例TMD患者随机分为3组,戴用不同高度咬合板使咬合距离分别增加3mm、5mm、7mm,比较分析戴板前和戴板后即刻测量的双侧颞肌前束(TA)和咬肌(MM)肌电电位。结果:在静息及紧咬状态下,戴用不同高度咬合板即刻测量的TA及MM肌电电位均明显低于戴板前的测量值(P<0.05);紧咬状态下5mm和7mm咬合板对MM肌电电位的降低程度显著高于3mm组。结论:咬合板是治疗肌功能紊乱的有效方法。高度为5mm和7mm的咬合板降低咀嚼肌肌电的能力较3mm咬合板更强。     

Control of vertical position of the maxilla in orthognathic surgery: clinical application of the sandwich splint

The Le Fort I osteotomy can be used to change the position of the maxilla in all three dimensions. A presurgically fabricated occlusal splint is used to reproduce the planned sagittal and transverse position of the maxilla. Various methods for determining the proper vertical position have been described. The major difficulty in vertical control when these techniques are used is the sagittal change of the lower reference point as the maxilla is advanced. The relative error in the vertical plane increases with larger sagittal movements. The sandwich splint technique, with two stable intraoral reference points, can be used to ensure proper vertical positioning of the maxilla. This method enables exact measurement of the vertical dimension during cast surgery and in the operating room. Vertical measurements are based on the relationship between the mandible and skull base. This distance remains constant during splint fabrication and when the splint is used at surgery. Postoperatively, the mandible can be rotated into the new centric occlusion.     

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.     

数字化耠板在儿童颞下颌关节强直合并颌骨畸形同期治疗中的应用：附2例报告

目的：探讨数字化验板在儿童颞下颌关节强直合并颌骨畸形同期治疗中的应用效果。方法：2例儿童单侧颞下颌关节强直合并颌骨畸形患者,术前采用SurgiCaseCMF5．0软件进行颌骨畸形的三维测量．模拟骨球截除后摆正下颌骨,制作数字化袷板,术中应用,行肋骨一软骨移植关节重建。术后进行CT扫描二三维测量,评价应用效果。结果：2例患者术中袷板戴入顺利,术后CT三维测量与术前设计吻合度高。结论：数字化袷板在儿童颞下颌关节强直合并颌骨畸形的同期治疗中节省了手术时间,提高了手术的准确性,具有较好的临床应用前景。     

Influence of Occlusal Splints on Bilateral Anterior Temporal EMG Activity during Swallowing of Saliva in Patients with Craniomandibular Dysfunction

A full-arch maxillary stabilization occlusal splint was made for each of 10 patients with craniomandibular dysfunction. These splints were divided into three sections (one anterior and two posterior). This procedure allowed variation in the anteroposterior centric localization of occlusal contacts, thus permitting the recording of the EMG effects produced by the different occlusal splint sections. The integrated EMG activity was recorded from the right and left anterior temporal muscles during swallowing of saliva in habitual occlusion and with the different occlusal splint sections inserted. EMG activity during swallowing of saliva was significantly lower with the different occlusal splints than in habitual occlusion. This supports the rationale for diurnal wear of the occlusal splint. No differences in EMG activity were found during swallowing of saliva when different sections of the occlusal splints were used. This fact points out the possibility for therapeutic use of different occlusal splints for improving swallowing function.     

Influence of the vertical dimension in the treatment of myofascial pain-dysfunction syndrome

Occlusal splints constructed at three different vertical heights were used to study the influence of vertical dimension in the etiology of bruxism and MPD syndrome. The vertical dimension of least EMG activity was determined for each of 75 patients who were randomly divided into three groups according to the vertical dimension at which the occlusal splint was constructed. Group I occlusal splints were constructed at 1 mm from the occlusal vertical dimension, group II splints at 4.42 mm, and group III splints at 8.15 mm. Results showed a faster and more complete reduction in clinical symptoms for groups II and III than for group I. The temporary use of occlusal splints with a vertical height exceeding the physiologic rest position did not encourage a greater muscular tonus or hyperactivity of jaw muscles. It can be concluded that elongation of elevator muscles to or near the vertical dimension of least EMG activity by means of occlusal splints is more effective in producing neuromuscular relaxation.     

垫治疗青少年颞下颌关节紊乱病的临床疗效分析

目的：考察[牙合]垫对青少年颞下颌关节紊乱病患者临床症状的改善情况。方法：采用稳定性[牙合]垫或再定位[牙合]垫治疗71例颞下颌关节紊乱患者，比较治疗前后张口度、颌面部疼痛和关节弹响的变化情况。结果：治疗组51例患者中疼痛34例，张口受限15例，疼痛伴张口受限14例，单纯性疼痛20例，治疗后疼痛及张口受限均得到缓解，缓解率为100％。治疗前疼痛指数和张口度分别为7．5±2．09和26．5±5．12mm，治疗后分别为2．4±1．58和40．1±5．03mm，差异均有显著性（P〈0．05）；关节弹响41例，治疗后18例弹响消失，16例弹响减轻。对照组中有2例弹响自行消失，3例疼痛自行缓解，其余无变化，差异有统计学意义（P〈0．05）。结论：[牙合]垫对颞下颌关节紊乱病患者的临床症状有显著缓解作用。     

Condylar position control during maxillary surgery: the condylar positioning appliance and three-dimensional double splint method

A new method for positioning the maxilla and condyle after Le Fort I osteotomy maintains the patient's vertical dimension (ie, the relation of the mandible to the skull above the osteotomy plane) in the preoperative and postoperative positions during both cast surgery and actual surgery. During surgery the condylar positioning appliance is fixed to the anterolateral zygoma and the lateral cortex of the mandibular ramus bilaterally to orient the mandible in centric relation. The condylar positioning appliance is used with the three-dimensional double splint method. Two prefabricated splints enable three-dimensional positioning of the maxilla in the fixed mandibular position during surgery. Postoperatively, the mandible can be rotated into the new centric occlusion.     

Correction of jaw deformities involving simultaneous osteotomy of the mandible and maxilla.

A one-stage surgical correction of gnathic deformities involving both jaws is described. It permits both the establishment of a normal occlusion and correct alignment of the occlusal plane to the skull. The osteotomy commences with the mandible. Its new position is oriented to the (as yet) untouched maxilla with the aid of an intermediate occlusal splint produced as a result of cephalometric evaluation and cast model surgery. The mandible is secured at its osteotomy sites by bone screws, in the correct final position. The maxilla is then oriented to the mandible, now correctly positioned with the aid of a second, preformed occlusal splint again produced on the basis of cast model surgery. Following intermaxillary fixation and internal wire suspension the splint is left in place until bony consolidation has taken place. External fixation is not required. The procedure enables the cephalometrically established measurements for the movements of both jaws to be easily reproduced with a high degree of accuracy. The technique is described in detail and discussed on the basis of clinical examples.     

Effect of occlusal splints on the electromyographic activities of masseter and temporal muscles during maximum clenching.

OBJECTIVES: Despite the broad use of occlusal splints in the treatment of temporomandibular disorders, the efficacy of splints is a source of controversy. In this study, the effectiveness of occlusal splints on the electromyographic activity of the masseter and temporal muscles in healthy individuals was investigated. METHOD AND MATERIALS: An occlusal splint was made for 25 healthy individuals. Surface electromyographic recordings were done during maximum clenching without the splint and immediately after application of the splint. The relative level of activity in the masseter and temporal muscles was quantified by means of activity index. Paired t test and Wilcoxon signed-rank tests were used for data analysis. RESULTS: The mean electromyographic activities of masseter and temporal muscles (in mV/s) were 0.7712 and 1.0488 without the splint and 0.8396 and 0.9276 immediately after application of the splint. There was no significant difference between the electromyographic activities of both muscles before and after insertion of the splints. The activity index increased after application of the occlusal splints. This increase was also insignificant. CONCLUSION: Immediate application of occlusal splints has no significant effect on the activity of masseter and temporal muscles. It could decrease the relative activity of the temporal to the masseter muscle (increasing the activity index).