应用CAD/CAM技术进行个体化下颌骨重建

目的:探讨计算机辅助设计和制造技术(CAD/CAM)应用于下颌骨肿瘤切除术后骨缺损的个体化修复重建。方法:选择面部畸形明显的单侧下颌骨成釉细胞瘤4例,术前行下颌骨螺旋CT扫描,三维重建成像,用CAD/CAM数控技术和镜像技术,制成与患者骨组织完全相同的个体化实体模型,根据模型预弯制重建钛板。手术切除病灶下颌骨,切取髂骨节段,植于重建板的舌侧,固定重建板于正常下颌骨端。结果:CT三维重建影像与实体模型测量数据接近;预弯制钛重建板与下颌骨匹配;手术恢复了下颌骨的连续性和功能,面部外形对称,X线片显示重建的下颌骨高度和厚度适中。结论:CAD/CAM技术为术前设计提供了个体化实体模型,提高了手术的精确性,节省了手术时间,降低了手术并发症。     

A modified surgical approach for the treatment of mandibular unicystic ameloblastoma in young patients

BackgroundUnicystic ameloblastoma is a distinct clinicopathological entity with its cyst-like radiographic appearance and occurrence in the mandible of young patients. Surgical resection of the mandible leads to jaw deformity and challenging reconstruction burden, especially among young patients. Conservative treatment, however, results in less serious function and esthetic impairment.PurposeWe aimed at evaluating dredging method as an alternative conservative surgical approach in young patient with large unicystic ameloblastoma.Patients and methodsTwenty patients (n=20) with histologically-diagnosed unicystic ameloblastoma were recruited for this prospective study. The surgical treatment protocol comprised an initial deflation (marsupialization) step, followed by later enucleation and subsequent repeated separate dredging procedures.ResultsThe study population comprised 16 males and 4 females. The average age at the time of diagnosis was 18.5 years. At the last follow-up period, achievement of normal mandibular bone contour with no radiographic signs of recurrence was evident.ConclusionThe dredging method as a modified surgical technique may represent a reliable approach for management of unicystic ameloblastoma in young patients.     

The CAD–CAM technique for mandibular reconstruction: An 18 patients oncological case-series

BackgroundModern techniques for mandibular reconstruction, such as CAD–CAM, offer new solutions for planning of reconstructive surgery in relation to the aesthetic outcome and the prosthetic rehabilitation.MethodsCAD–CAM reconstruction procedures using vascularised bone free-flap transfers and surgical guides to cut the mandible and fibula were performed in 18 cases of neoplasms. The planned surgery was used to design and manufacture customised surgical devices.ResultsThe mean follow-up was 12 months. All patients, except one, are alive without disease at the time of writing. Reconstructive microvascular flap survival was 100%. No major or minor microvascular complication occurred. No donor site complication was observed.ConclusionsCAD–CAM technology is a very useful way to obtain the native morphology of the mandible, especially when both bi-dimensional and tri-dimensional defects occur. The reconstruction protocol presented offers several benefits and few disadvantages, which are discussed in the article.     

CAD/CAM制作个性化钛网联合髂骨移植重建单侧下颌骨大型轮廓缺损

目的 探讨CAD/CAM技术联合个性化预成型钛网及游离髂骨移植修复单侧下颌骨大型轮廓缺损的可行性及有效性.方法 选取四川大学华西口腔医院正颌及关节外科2015年11月—2019年12月的15例单侧下颌骨大型轮廓缺损的患者.采用基于逆向工程的计算机辅助设计/计算机辅助制作(CAD/CAM)技术,镜像重建患侧下颌骨轮廓并制...     

犬下颌骨节段性缺损的个体化再生修复实验研究

目的:通过实验观察犬下颌骨节段性缺损个体化再生修复的效果,为计算机辅助个体化再生修复下颌骨缺损的技术和方法向临床过渡提供依据。方法:利用计算机辅助设计/制作、快速原型技术等设计制作实验动物下颌骨个体化三维中空钛网修复体,再将其与β-磷酸三钙和松质骨髓植入联合应用于犬下颌骨节段性缺损的修复,通过X线片、大体标本和组织学切片对下颌骨节段性缺损的个体化再生修复效果进行观察。结果:犬下颌骨解剖形态恢复十分理想,组织学和X线摄影观察显示钛网内具有新骨形成,新生骨在3个月时已十分明显和成熟。结论:将计算机辅助技术与骨再生材料联合应用,可望通过骨再生途径实现下颌骨节段性缺损的个体化修复重建。     

计算机辅助设计下颌骨带种植体三维钛网的实验研究

目的:探讨利用计算机辅助方法,制作可用于下颌骨个体化功能性重建的修复体,为下颌骨个体化功能性修复探索新的方法。方法:首先通过CT扫描获取下颌骨断层解剖信息,然后运用三维重建、镜像及快速原型技术获得拟修复下颌骨复原实体模型,在此基础上利用铸造手段完成个体化三维钛网修复体的制作,然后将种植体与钛网相连接,构建个体化功能性修复体。结果:以CT扫描获取下颌骨断层解剖信息为基础,通过计算机辅助成功制作了带种植体的个体化钛网修复体,与相应的下颌骨标本连接匹配良好,个体化恢复了骨缺损的连续性,所带种植体为进行种植义齿修复恢复理想的咀嚼功能提供了可能。结论:在CT扫描获取下颌骨原始解剖信息的基础上,通过计算机CAD/CAM过程,能够成功构建下颌骨个体化功能性修复体,为临床个体化功能性颌骨重建提供了一种新的途径。     

CAD/CAM联合游离腓骨肌皮瓣修复双侧下颌骨大范围骨缺损

目的:探讨恢复双侧下颌骨大范围骨缺损的解剖外形、重建患者咬合功能的有效方法。方法:对病变累及双侧下颌骨、需进行(或已进行)节段性骨切除术的15例患者行术前CT扫描,提取扫描数据,采用CAD/CAM快速原型技术行数字化颅颌面骨三维重建和下颌骨实体模型打印。在实体模型上设计截骨区间和钛网外形,数控成型机冲压钛网,使预成钛网与缺损区下颌骨外形完全一致。切取腓骨肌皮瓣,血管化游离移植联合预成钛网植入完成下颌骨缺损的修复重建。结果:15例患者腓骨肌皮瓣全部存活,创口愈合良好,下颌骨解剖外形包括自然弧度、曲率和高度恢复满意,同期修复者手术前后容貌无明显变化。结论:CAD/CAM快速原型技术联合游离腓骨肌皮瓣移植修复双侧下颌骨大范围节段性骨缺损,不仅可以最大限度地重建下颌骨的自然外形,维持患者容貌,也为种植体植入及咬合功能重建创造了良好条件。     

下颌第一磨牙平台转移种植体三维有限元模型的建立

目的 构建下颌第一磨牙平台转移种植体的三维有限元模型.方法 选择健康成年男性下颌骨1例进行螺旋CT扫描,将得到的DICOM数据导入Mimics 10.01软件中,建立下颌骨及牙齿的三维几何模型,并用Geomagic studio12软件进行曲面优化;利用UG NX6.0软件建立平台转移种植系统(韩国DIO种植体系统)的三维几何模型;最后将各部分模型导入Hypermesh10.0软件中进行装配组合、网格划分以及材料属性赋值.结果 成功建立了下颌第一磨牙平台转移种植体的三维有限元模型,该模型与实际模型有高度的几何相似性,其网格质量较高、力学性能好.结论 结合CT扫描技术和多种有限元建模软件能够快速、精确地建立下颌第一磨牙平台转移种植体的三维有限元模型,为后续平台转移种植体进行有效的生物力学研究提供基础.     

The use of titanium mesh plates for graft fixation in mandibular osteoplasty

Opportunities of the use of mesh titanium plates as fixing devices are considered at reconstruction operations. Data of following up 8 patients with defects of the mandible of various location and extent are analysed. They were operated with reconstruction of the mandible with iliac graft and bone graft fixing with the mesh titanium plates. A technique of the operations is described, a case of successful use of mesh titanium implant modelled by the form of the mandible in repair of the mandible defect. The analysis of long-term results shows the potential efficiency of the use of mesh titanium plates as fixing adaptations in bone plastic operations.     

Three-dimensional virtual technology in reconstruction of mandibular defect including condyle using double-barrel vascularized fibula flap

ObjectiveThe aim of this study is to demonstrate the reconstruction of mandibular defects including the condyle using a double-barrel vascularized fibula flap aided by three-dimensional virtual technology.MethodsTen patients with the type H mandibular defects, who had undergone mandibular reconstruction using a double-barrel vascularized fibula flap, were reviewed for this study. Prior to the surgery, the patients CT scan data were analyzed virtually using SimPlant Pro? software (version 11.04). The simulation allowed construction of an individual mandibular model serving to guide the clinical operation.ResultsThe preoperative virtual surgery greatly benefitted the actual surgery. The vertical height of the neomandible and facial contour were precisely predicted. Some minor complications were encountered. Postoperative three-dimensional reconstruction revealed a close match with the simulated condyle.ConclusionA double-barrel vascularized fibula flap can provide sufficient bone, both in length and vertical height, for the reconstruction of a type H mandibular condylar defect. Combined virtual three-dimensional reconstruction and rapid prototyping can improve postoperative outcomes in mandibular reconstruction.     

The pattern and occurrence of ameloblastoma in adolescents treated at a university teaching hospital,in Kenya: A 13-year study

Ameloblastoma presenting in the adolescent age group is rare with few studies documenting their occurrence.AimThe aim of this study was to carry out an analysis of the pattern and occurrence of ameloblastoma in those less than 20 years of age.Materials and methodPatients from the University of Nairobi Dental teaching Hospital treated for ameloblastoma were included in the study over a 13-year period. The study highlights the demographic, clinic-radiographic and histologic features of benign locally aggressive lesions.ResultsA total of 127 patients were recorded of which, 27 (21.3%) were below the age of 20 years; no case was reported below the age of 10 years. 18.5% were below the age of 14 years and 81.5% were 15–19 years old. The gender predilection was ～1:1. All of the tumours occurred in the mandible, with radiographic features of a multilocular radiolucencies (85.2%); and a fewer unilocular lesions (14.8%). The management is in a staged-wise approach: resection and/or disarticulation with temporary reconstruction using mandibular stainless steel or titanium plates and delayed bone grafting.ConclusionThe occurrence of ameloblastoma can mimic an odontogenic cyst, clinicians therefore need to be vigilant when examining adolescents so that conservative treatment is started early in order to reduce the subsequent morbidity.     

腓骨瓣及CAD/CAM技术在重建下颌骨缺损中的应用

目的　探讨应用腓骨瓣及CAD/CAM技术修复大面积下颌骨缺损的经验。方法　根据16例患者下颌骨缺损的部位和特征,通过螺旋CT扫描获取缺损区的数据,在软件中应用CAD/CAM技术模拟下颌骨切除及重建手术,利用快速成型机加工制作出实物模型,依据模型对腓骨进行塑形、钛板重建,恢复下颌骨的形态和功能。结果　CAD/CAM技术的应用使术中截骨、腓骨塑形、定位速度明显加快;术后患者面部外形基本对称,影像学检查显示下颌骨缺损区的重建形态及固位良好;无严重并发症。结论　腓骨瓣联合CAD/CAM技术重建下颌骨缺损,能够明显缩短手术时间,提高手术质量,保证手术效果,是值得推广的重建下颌骨缺损的理想方法。     

Local and systemic risk factors influencing the long-term success of angular stable alloplastic reconstruction plates of the mandible

IntroductionAfter ablative surgery of the mandible, angular stable alloplastic reconstruction plates are commonly employed. The aim of the study was a long-term evaluation of local anatomical, as looking at systemic factors influencing specific complications and the failure rate of such plates.Materials and methodsIn a retrospective study covering an 11-year period, we reviewed the outcomes of angular stable plates of patients who had a segmental resection of the mandible and subsequent alloplastic reconstruction. Complications and failure rates were assessed and local (anatomical size and localization of resection) as well as systemic risk factors (age, sex, radiation therapy, smoking) evaluated.ResultsAltogether, 162 plates were reviewed. The overall complication rate was 28% (fractures n = 8, loose screws n = 7, dehiscences n = 31) after an average time of 13 months. Cumulative survival rates of 73% after one, of 67% after 2, of 59% after 3 and of 40% after five years were observed. We found a significant correlation of increasing defect sizes to a rising complication and failure rate. Plate dehiscence occurred more often in defects including the midline (p = 0.005). Though not statistically significant, the occurrence of plate fracture was associated with lateral mandibular defects (7/8, p = 0.113). In smoking patients an earlier failure rate was seen.ConclusionThe results clearly indicate that the success of alloplastic reconstruction plates of the mandible is dependent on various risk factors. They should – if possible – be used temporarily only. If not done primarily, a secondary approach with bone reconstruction is recommended.     

Rare case of giant unicystic ameloblastoma: Luminal variant

Objective and importance: Ameloblastoma is a locally aggressive benign tumor, commonly occurring in the mandible. While giant ameloblastoma of multicystic or plexiform variant have been reported, the authors report a rare case of giant unicystic ameloblastoma of luminal variant, which was treated by compartmental resection and planned for delayed reconstruction.

Clinical presentation: A 46 year old male patient reported to the oral surgery out-patient department with a swelling of the left side mandible region of 2 years duration. He had undergone ayurvedic treatment for the same with no improvement. The size of the lesion on presenting was approximately 9 × 12 cm.

Intervention: Compartmental resection with plan for secondary reconstruction, after adequate follow up period.

Conclusion: While conservative management is being explored as a treatment option for unicystic ameloblastoma, resection is still the standard of care regardless of the histopathological subtype for giant lesions.     

Ameloblastoma: a retrospective single institute study of 34 subjects

Objective: This study aims to clarify demographic and clinical aspects of patients with ameloblastoma treated at a single Finnish institute during 1985–2016. Associations between predictor variables (gender and age) and outcome variables (location, tumour type, growth patterns and average tumour size) were sought.

Materials and methods: A retrospective cohort study was designed and implemented including 34 patients diagnosed with primary ameloblastoma and treated at the Helsinki University Central Hospital. Patient records were investigated, and tissue samples re-evaluated. The chi-square test was used on all categorized variables and t-test for continuous ones. A p value equal to or under .05 was considered significant.

Results: Males were slightly more predominant among the Finnish patients with ameloblastoma. Maxillary tumours were seen exclusively in male patients (p?=?.034). Additionally, these patients were older than patients with mandibular tumours (p?=?.007). A mixture in histological growth patterns was more common than originally anticipated. The study revealed a wide range of clinical signs and subjective symptoms, of which pain or other sensations were experienced most often.

Conclusions: This study of 34 subjects shows that southern Finnish patients with ameloblastoma do not substantially differ from patients in similar study designs.     

Treatment of orbital blowout fracture using a customized rigid carrier

PurposeThis study aimed to examine the usefulness of treating orbital blowout fracture using a customized rigid carrier.Material and methodsPatients who underwent surgery for orbital blowout fractures in our department from April 2016 to March 2019 were recruited in the study. We molded a rigid thermoplastic material into the same shape as the reconstruction material according to the 3D model and transplanted it into the orbital space along with the reconstruction material. We assessed Hertel exophthalmometry, awareness of diplopia, and the Hess area ratio (HAR%).ResultsWe performed this procedure in 15 patients with blowout fractures. Reconstruction materials used were iliac bone, absorbable plates, and titanium mesh in 12, 2, and 1 patient, respectively. None of the patients showed a difference of more than 2 mm on Hertel exophthalmometry. Only one patient had diplopia after surgery. The average preoperative and postoperative HAR% were 83.1 and 90.6, respectively. HAR% was more than 85% in 6 of 7 postoperative cases.ConclusionsThis method can be applied for surgery using various reconstructive materials and can be a useful method, especially in patients with a wide range of orbital bone defects.     

邻面边缘提升术在后牙椅旁即刻修复中的应用

目的 评价后牙邻面边缘提升术后即刻椅旁修复的临床效果。方法 选择49颗邻面缺损达龈下的后牙,邻面边缘提升后,采用CEREC椅旁CAD/CAM修复系统即刻完成修复体并粘接。1年后,参照改良修正后的美国公众健康服务标准,在修复体边缘染色、边缘继发龋、边缘适合性、崩瓷折裂或脱落、修复体颜色及牙龈健康状况6个方面进行评价。结果 邻面边缘提升后的修复体在边缘染色、继发龋、边缘适合性等6个方面的临床评级A级成功率均达93.88%以上,其中修复体边缘染色、边缘适合性以及修复体颜色的A级成功率可达100%。结论 运用邻面边缘提升和CAD/CAM即刻椅旁修复完成的修复体,临床效果良好。     

Custom made bioceramic implants in complex and large cranial reconstruction: A two-year follow-up

IntroductionLarge cranial defects still represent a challenge in neurosurgery. Currently different biomaterials are available for cranial reconstruction including titanium, acrylic mesh and different types of calcium phosphate-based bone grafts. The goal of surgery is a perfect fit of the implant without infection and absorption, and a good aesthetic result. This paper describes a surgical method for cranioplasty, using a customised porous hydroxyapatite (HA) prosthesis.Materials and methodsSixty patients treated surgically with a customised porous-HA prosthesis for large cranial defects, were followed retrospectively. A two-year follow-up was carried out with periodic visits and CT scans. Safety (the incidence of adverse events and fractures of the implant) and clinical performance (biological and cosmetic results) were evaluated.ResultsFifty one patients were followed-up, no rejection occurred and only one case of infection was recorded. Five patients had minor surgery-related complications, and no spontaneous implant fractures or mobilisation were reported. Three patients exhibited implant fractures as a result of trauma and all healed spontaneously. All patients showed a satisfactory clinical outcome with good cosmetic appearance in the early postoperative period and after a long-term follow-up.ConclusionsCranioplasty performed with a customised porous-HA prosthesis gave a positive outcome, showing it to be an appropriate technique for use in large and complex cranial reconstruction.     

Double anterior (anterolateral and anteromedial) thigh flap for oral perforated defect reconstruction

ObjectiveThe purpose of this study was to assess the therapeutic efficacy of oral perforated defect reconstruction with a double anterior (anterolateral and anteromedial) thigh flap through the modified lateral lip-submandibular approach.Materials and methodsFrom July 2010 to August 2013, eight patients with oral perforated defects secondary to oral cancer ablation involving the superior partial mandible or the posterior partial maxilla, with immediate reconstruction by double anterior (anterolateral and anteromedial) thigh flaps, were retrospectively enrolled into this study.ResultsAll double anterior flaps were musculocutaneous flaps. Seven double flaps resulted in good functional and aesthetic outcomes with complete flap survival. One patient required operative exploration in the postoperative period due to thrombosis in the external jugular vein. After the salvage, one of the double flaps in the intraoral region resulted in partial failure of the superficial skin of the flap. No functional impairment at the donor sites occurred in any of the cases.ConclusionThe double anterior (anterolateral and anteromedial) thigh flap is a feasible and acceptable technique for reconstruction of an oral perforated defect involving the mandible or the maxilla through the modified lateral lip-submandibular approach. It presents a very acceptable aesthetic and functional result with the additional advantage of low morbidity at the donor site.     

Der „anterolateral thigh perforator flap“ zur Deckung von Gesichtsdefekten nach Tumorchirurgie

Background

Individual flap design and minor donor site morbidity are main criteria in the treatment of facial defects after tumour surgery. Microvascular perforator flaps seem to follow these criteria well. In the following study our experiences with microvascular anterolateral thigh perforator flaps (ALTPF) in reconstruction of the face following ablative tumour surgery are described and discussed in comparison to the present literature.

Patients and methods

In 19?patients with squamous cell carcinomas of the floor of the mouth (8), the cheek (6) or the mandible (5) of stadium T3 or T4 ablative tumour surgery followed by reconstruction was performed. For covering the soft tissue defects 19?ALTPF were used. In the five patients with carcinomas of the mandible a microvascular iliac crest transplant was combined with the anterolateral thigh perforator flap for complete chin reconstruction.

Results

In one patient an intraoperative dissection of the perforator vessels happened. In all other patients surgery and postoperative period was free of complications. Five patients had minor second surgery for aesthetic of functional reasons. At the end there were good aesthetic and functional results in every patient.

Conclusions

The anterolateral thigh perforator flap is of great advantage in reconstruction of the face after tumour surgery. Individual designing, central and save perfusion, easy to be controlled, and a low incidence of donor site morbidity are their main advantages.