肿瘤术后颌骨缺损的功能重建

目的：肿瘤术后造成的颌面缺损使患者丧失咀嚼、语言等功能，并导致颜面畸形。采用植骨种植功能颌面建，以提高患者的生存质量。方法：本组64例肿瘤术后颌骨缺损（上颌10例，下颌54例）所用3种方法：（1）下颌骨部分或全部缺损，采用血管化或非血管化骨移植延期（同期）牙种植，完成种植义齿修复；（2）一侧上颌骨缺损，健侧缺牙或无牙，采用健侧牙种植完成赝复修复；（3）双侧上颌骨缺损，采用颧骨种植，通过磁附着固位完成义颌赝复修复。结果：64例所用3种方法均达到恢复外形与功能理想的效果。观察时间最长12年，最短5年，其中6枚种植体未实现骨结合。上颌缺损修复的种植体存留率为97．5％；下颌骨缺损血管化植骨种植为97．1％；非血管化植骨种植为97．7％。结论：上颌骨缺损采用种植赝复修复可行，若颧骨较薄，应先植骨；植骨－种植是下颌骨功能重建理想的方法。血管化植骨种植适用于植骨床血运差的患者；非血管化植骨种植方法简单，易于推广。因缩短了移植骨的离体时间，骨细胞仍有活性，与血管化骨移植效果一致。证实了自体骨植骨块兼有骨形成、骨诱导及骨传导作用。     

种植与颌骨缺损功能重建

颌骨缺损往往同时伴有大鼍牙齿的缺失,对患者面容及功能的影响举足轻重.因此,如何在颌骨缺损重建的基础上,早期恢复咀嚼功能与美学形态,是颌骨重建研究中的一个重要而关键的问题.然而,随着口腔种植技术、显微外科技术、计算机应用技术的开发和深入,尤其是将种植体引入到移植骨的功能重建后,标志着颌骨缺损修复真正进入了一个功能重建的时...     

基因治疗干预颌骨重建的研究进展

基因治疗在颌骨修复重建中的应用近年来得到了极大的发展.本文就基因治疗在促进颌骨缺损修复和牙周重建等方面的研究进展作一综述.     

游离腓骨肌皮瓣在颌骨缺损修复重建中的应用

目的探讨应用游离腓骨肌皮瓣修复颌骨缺损的经验。方法根据12例患者颌骨缺损的部位和特征．对腓骨进行塑形、钛板固定．恢复颌骨的形态和功能．并对面部形态的恢复及并发症的发生等进行评价。结果所有腓骨肌皮瓣修复颌骨缺损均获得成功．患者外形恢复满意，无明显并发症。结论游离腓骨肌皮瓣是修复颌骨缺损的一种理想方法。     

核素骨显像技术在颌骨组织缺损重建中的应用

如何修复颌骨缺损是目前口腔颌面外科重点研究方向之一。骨组织工程成为修复颌骨缺损的重要手段，核素骨显像技术则为及时准确地判断缺损修复成功与否、成骨活性和骨组织是否具有再血管化带来了新的希望。     

三焦点牵引成骨下颌骨缺损重建的实验研究

目的探讨采用内置式三焦点牵引器在犬下颌骨骨段缺损功能重建中牵引成骨的特点、规律。方法使用内置式三焦点牵引器对4只成年犬下颌骨骨段缺损进行牵引成骨重建。制作3cm下颌骨缺损区,同期植入内置式三焦点牵引器。牵引间歇期8天,牵引速度0.5mm×2次/天,稳定期3个月。结果下颌骨牵引成骨约30mm,牵引成骨过程中无感染、成骨不良等并发症。牵引完成后第3个月X线片、组织学观察及扫描电镜观察均可见新生骨的形成,新生骨的形态、组织结构接近正常下颌骨。结论三焦点牵引成骨技术重建的颌骨形态、组织结构和功能接近正常颌骨,牵引成骨区和压力成骨区局部应用rh-BMP2可以促进新骨的形成及钙化。     

3D打印技术在颌骨缺损修复重建教学中的应用

目的：探讨3D打印技术应用于颌骨缺损重建的临床教学效果。方法：利用颌骨数字化三维可视重建及3D打印技术制备模型,进行上下颌骨缺损重建的临床教学。结果：学生对上下颌骨缺损的解剖特点和修复重建方法有了更直观的认识,通过模拟手术操作,对颌骨缺损的手术修复方法、要点及咬合功能重建有了更深认识。结论：在颌骨缺损重建临床教学中引入3D打印技术,能使学生较好地理解和掌握教学内容,提高了解决实际问题的能力,是临床教学改革的重要手段。     

颌骨缺损患者的种植修复咬合重建

目的：探讨颌骨缺损患者种植修复重建咬合的方法以及临床效果。方法：对10例颌骨缺损患者进行种植修复咬合重建,除1例采用固定修复外,其余均采用活动义齿修复,其中采用磁性固位的覆盖义齿修复3例,杆卡式修复2例,球帽式修复2例,套筒式覆盖义齿修复1例,栓道式精密附着体修复1例。结果：经过12～48月的临床观察,除杆卡式修复的1例患者由于软组织较厚,牙龈在带入6月时出现增生外,其余患者未发生任何临床症状。38枚种植体均形成良好的骨结合,临床效果满意。结论：应用种植技术结合适当的修复方法能够使颌骨缺损获得良好的咬合功能及美学效果。     

颌骨缺损种植修复的研究进展

颌骨是颜面部外形的主要支撑结构，是咀嚼与语音功能的主要承担部位。颌骨的不完整性直接影响患者的1：2腔功能及面部外形。本文主要回顾颌骨缺损种植修复重建的现状及研究进展。     

浅谈颌骨缺损功能重建应注意的问题

<正>颌骨是口腔颌面部重要组成部分,对于维系面容,行使咀嚼、语言、吞咽、表情等功能起着重要作用。颌骨缺损必然导致面容与这些特定功能的严重毁损,势必给患者带来严重的心理和生理障碍,为此     

Computer-assisted surgical planning and simulation for condylar reconstruction in patients with osteochondroma

We describe the use of computer-assisted three-dimensional surgical planning in condylar reconstruction by vertical ramus osteotomy for patients with osteochondroma, and its clinical effects. Seventeen patients with osteochondroma of the mandibular condyle who were seen from March 2005 to March 2009 were divided into 2 groups treated by condylectomy and condylar reconstruction using vertical sliding osteotomy of the mandibular ramus with and without three-dimensional simulation using Surgicase CMF Materialise software. Clinical examination, radiographs, photographs, and details of operation and outcome were used postoperatively to evaluate the clinical effects of the technique. Satisfactory mouth opening was achieved in all cases. Mean (SD) osteotomy and fixation time, duration of intermaxillary fixation, and degree of postoperative numbness of the lower lip were considerably reduced among patients who had three-dimensional simulation. The combined use of computer-assisted three-dimensional surgical planning and simulation with vertical ramus osteotomy to reconstruct the condyle for patients with osteochondroma after excision of the tumour makes the operation more accurate and more convenient, and avoids damage to vital structures.     

Economic analysis of a low-cost virtual surgical planning protocol for mandibular reconstruction: a case series

The aim of this study was to make an economic analysis and evaluation of a low-cost virtual surgical planning (VSP) protocol that was developed in house, and based on open-source software and a desktop 3-dimensional printer. All eight patients between April 2014 and 2015 who had been treated by mandibular reconstructions with microvascular fibular flaps that had been planned using the protocol were retrospectively analysed for accuracy, time, and cost. Median differences for planned compared with postoperative intercondylar distance, intergonial distance, and gonial angle did not differ significantly. A median (range) labour time of 85 (€57-124) minutes was needed. An evaluation of cost, including labour, showed an additional median (range) cost/patient of € 276 (€257.50-297.25). With the acquisition cost of the 3-dimensional printer omitted, there was a negligible additional cost/patient of €44.75 (€26.25-66). All planning was done by the junior surgeon and there was a steep learning curve. Our new VSP protocol is cost-effective, easy to use, and has an accuracy comparable with that of a standard VSP protocol. To the best of our knowledge this is the first report of an open-source software protocol in which the labour costs of the planning by a surgeon are included.     

Reproducibility of a three-dimensional skeletal-based craniofacial orientation method for virtual surgical planning

Inadequate craniofacial orientation of computed tomography (CT) scans can have significant implications in all three planes of space. The purpose of this study was to present the reproducibility of a 3-dimensional skeletal-based method of craniofacial orientation for virtual surgical planning. The protocol was defined by landmarks commonly used for cephalometry, and required identification of basion, nasion, right porion, and right orbitale, and navigation in all CT views (coronal, sagittal, and axial) for correction of yaw, roll, and pitch. Reproducibility of the method was assessed using eight CT scans that were randomly selected and anonymised. The observer group consisted of six oral and maxillofacial surgeons with varying levels of experience (resident or faculty) who performed craniofacial orientation according to the proposed method. Results were expected to be below 2° of variation, when overall accuracy as well as the influence of the academic level of the observers and symmetry of the evaluated anatomy, were considered as independent variables. Overall accuracy for all cases and for yaw, roll, and pitch were always below 2° of variation, without influence of level of experience and symmetry. Interobserver assessment was categorised as excellent in all instances, and intraobserver evaluation demonstrated consistency in the orientation of all axes. The proposed craniofacial orientation protocol presented in this study is easy to learn, applicable to computer-aided surgical planning, and can be performed by the non-technical clinician, resulting in excellent reproducibility and consistency.     

Evaluation of a novel algorithm for automating virtual surgical planning in mandibular reconstruction using fibula flaps

Virtual surgical planning plays an increasingly important role in jaw reconstruction. The aim of the present study was the evaluation of the clinical applicability of a novel algorithm for automating virtual mandibular reconstruction using fibula flaps.The software uses Computed-Tomography of the facial skeleton and the lower leg of 63 subjects, implemented in Python programming language. The developed algorithm is based on individual bone curvatures of the mandible and fibula. Ten different defects were generated for each mandible by virtually defined cutting planes. Three experienced surgeons reviewed all reconstruction proposals generated by the algorithm according to a visual analogue scale. The possible correlation between the ratings and the prioritization of the algorithm and the calculation time for the reconstructions were analyzed.Spearman analysis showed a strong correlation ?0.613 (p < 0.001) between the deviation of the reconstruction result from the target line and the average assessment of the surgeons as well as a moderate correlation ?0.448 (p = 0.013) between surgeons' assessments and the prioritization by the algorithm. The calculation time for twenty reconstructions per defect took between 4.99 s and 483.5 s depending on defect size and location.The evaluated algorithm automatically creates valid reconstruction results with acceptable computation time, which have received a high level of confirmation from experienced surgeons.     

Virtual planning,simultaneous dental implantation and CAD/CAM plate fixation: a paradigm change in maxillofacial reconstruction

Prosthetic rehabilitation in patients undergoing reconstructive surgery using vascularized free flaps is challenging, and functional rehabilitation of the patient with a fixed prosthesis is rare. Virtually planned maxillofacial reconstruction including simultaneous dental implantation according to the prosthodontic ideal position of the implants could further enhance dental rehabilitation. The data of 21 patients undergoing fibula free flap reconstructive surgery with CAD/CAM patient-specific reconstruction plates during the years 2015–2018 were analysed, including the applicability of the virtual plan, flap survival, duration of surgery, ischemia time, simultaneous dental implantation, implant exposure, and postoperative complications. The virtual plan could be translated to surgery in all cases. In total, 76 dental implants were simultaneously placed during primary reconstruction in the 21 patients. For 38.1% of these patients, the implants could be uncovered in secondary surgery; the mean duration until exposure was 7.6 months. The implant survival rate was 97.4% (74/76). Wound infection requiring a secondary intervention occurred in 23.8% of patients during follow-up. Virtually planned reconstruction with a fibula free flap, simultaneous dental implantation, and CAD/CAM plates allows early and functional dental rehabilitation. A dental workflow should be integrated into the virtual planning, and prosthetically favourable implant positions should determine the position of the fibula segments.     

Prosthetically driven, computer-guided implant planning for the edentulous maxilla: a model study

Objectives: To analyze computer‐assisted diagnostics and virtual implant planning and to evaluate the indication for template‐guided flapless surgery and immediate loading in the rehabilitation of the edentulous maxilla. Materials and Methods: Forty patients with an edentulous maxilla were selected for this study. The three‐dimensional analysis and virtual implant planning was performed with the NobelGuide? software program (Nobel Biocare, Göteborg, Sweden). Prior to the computer tomography aesthetics and functional aspects were checked clinically. Either a well‐fitting denture or an optimized prosthetic setup was used and then converted to a radiographic template. This allowed for a computer‐guided analysis of the jaw together with the prosthesis. Accordingly, the best implant position was determined in relation to the bone structure and prospective tooth position. For all jaws, the hypothetical indication for (1) four implants with a bar overdenture and (2) six implants with a simple fixed prosthesis were planned. The planning of the optimized implant position was then analyzed as follows: the number of implants was calculated that could be placed in sufficient quantity of bone. Additional surgical procedures (guided bone regeneration, sinus floor elevation) that would be necessary due the reduced bone quality and quantity were identified. The indication of template‐guided, flapless surgery or an immediate loaded protocol was evaluated. Results: Model (a) – bar overdentures: for 28 patients (70%), all four implants could be placed in sufficient bone (total 112 implants). Thus, a full, flapless procedure could be suggested. For six patients (15%), sufficient bone was not available for any of their planned implants. The remaining six patients had exhibited a combination of sufficient or insufficient bone. Model (b) – simple fixed prosthesis: for 12 patients (30%), all six implants could be placed in sufficient bone (total 72 implants). Thus, a full, flapless procedure could be suggested. For seven patients (17%), sufficient bone was not available for any of their planned implants. The remaining 21 patients had exhibited a combination of sufficient or insufficient bone. Discussion: In the maxilla, advanced atrophy is often observed, and implant placement becomes difficult or impossible. Thus, flapless surgery or an immediate loading protocol can be performed just in a selected number of patients. Nevertheless, the use of a computer program for prosthetically driven implant planning is highly efficient and safe. The three‐dimensional view of the maxilla allows the determination of the best implant position, the optimization of the implant axis, and the definition of the best surgical and prosthetic solution for the patient. Thus, a protocol that combines a computer‐guided technique with conventional surgical procedures becomes a promising option, which needs to be further evaluated and improved.