Construction of an Implant‐Retained Auricular Prosthesis with the Aid of Contemporary Digital Technologies: A Clinical Report

Implant‐retained auricular prostheses are a successful treatment modality for children with microtia. They involve only minor surgical intervention of implant placement and result in an esthetically pleasing outcome. Integration of digital technologies (DT) in the prosthetic reconstruction process is a new approach toward enhancing outcomes. In this report we present a case of auricular prosthetic reconstruction following two implant placements in the right mastoid region. The ear prosthesis was constructed with the aid of various DTs. A structured light laser scanner was used to digitize the nondefect patient ear. The digitized 3D ear was then manipulated in specialist software, mirrored to reflect the opposing side, and a Rapid Prototyping (RP) machine (Z‐Corp) was used to manufacture the soft tissue required. This RP‐mirrored ear model allows very accurate reproduction to replicate missing soft tissue. A color Spectrometer was used to accurately reproduce skin tones. The use of these technologies is now routine practice at our unit. They enhance prosthetic outcomes and esthetics, save the prosthetist's time, and are digitally stored and subsequently readily available and reproducible.     

前牙区数字化即刻种植即刻修复病例报道及文献回顾

目的：报道以修复为导向的上前牙美学区数字化即刻种植即刻修复技术。方法通过口内数字化光学扫描印模,结合CBCT扫描,CAD/CAM技术虚拟植入种植体、设计个性化钛基台穿龈形态及临时修复体,并生成种植手术导板及临时牙,辅助完成微创手术。结果本技术达到拔牙后即刻种植即刻修复的效果。即刻修复临时牙冠能够在病人第二次就诊手术后即刻完成,最终实现保存软组织轮廓的美学种植修复。结论种植应用数字化技术改变了以往工作流程,使美学种植修复更加简单、高效、精确。     

Fabrication of a craniofacial implant surgical and treatment planning guide

A procedure is described to fabricate a surgical guide to assist in the placement of craniofacial implants for prosthetic auricular rehabilitation. An impression is made of the defect, and a wax pattern of the missing ear is completed and evaluated on the patient. The definitive wax prosthesis is processed in acrylic resin. An occlusal maxillary splint is also fabricated. The occlusal splint and the acrylic resin ear are joined together using an extraoral acrylic resin bar. The resulting surgical guide provides proper orientation of the acrylic resin ear while remaining securely attached to the maxillary arch. This surgical guide can also be utilized for pretreatment radiographic examination.     

Full‐Arch Implant‐Supported Rehabilitation Guided by a Predicted Lateral Profile of Soft Tissue

In full‐arch implant‐supported rehabilitation of patients with severe periodontitis, prediction of lateral facial profile with modified dental position remains a challenge, especially for patients with protruded anterior teeth. This clinical report describes a digital workflow to predict lateral profiles and then guide the implant placement and restoration fabrication.     

A fully digital workflow to register maxillomandibular relation using a jaw motion tracer for fixed prosthetic rehabilitation: A technical report

Objective

This technique aimed to describe a fully digital workflow to register maxillomandibular relation for fixed prosthetic rehabilitation.

Clinical Considerations

Mandibular kinematics could be reproduced in a four-dimensional (4D) virtual patient based on the intraoral scan, facial scan, cone beam computed tomography, and jaw motion trajectory, which helped record centric relation and determine a proper occlusal vertical dimension in a virtual environment. The therapeutic position could be exported directly to the dental computer-aided design software for digital waxing design with a facial scan. The 4D virtual patient was also used to verify the functional and esthetic outcomes of provisional restorations.

Conclusions

This novel approach digitized the process of determination, delivery, and double-check of maxillomandibular relation, thus contributing to the establishment of a completely digital workflow for fixed prosthetic rehabilitation.

Clinical Significance

Registration of maxillomandibular relation, including centric relation and occlusal vertical dimension is critical to the success of prosthetic rehabilitation. Traditional procedures are complex and time-consuming, and heavily rely on the clinical experience of dentists. A fully digital approach to creating a 4D virtual patient and registering the maxillomandibular relation is established, which guides to determine a proper occlusal vertical dimension in centric relation. Digital delivery and double-check can simplify the conventional procedure and ensure that the determined maxillomandibular relation is reliable.     

Patient-reported outcome measures compared to professional dental assessments of monolithic ZrO2 implant fixed dental prostheses in complete digital workflows: A double-blind crossover randomized controlled trial

Purpose

This double-blind randomized controlled trial analyzed patient-reported outcome measures in terms of subjective patient satisfaction compared to objective dental evaluation of prosthetic treatment with 3-unit monolithic zirconium dioxide implant fixed dental prostheses (iFDPs) in 3 digital workflows.

Material and methods

Twenty patients were restored with 3 iFDPs each on Straumann TL-implants with 2 completely digital workflows using different intraoral optical scanning systems with model-free fabrication of the restoration (Trios 3/3Shape [Test-1]; Virtuo Vivo/Straumann [Test-2]), and mixed analog-digital workflow with conventional impressions and digitized gypsum casts (Impregum/3M Espe [Control]). The order of impression-taking and the prosthetic try-in were randomly allocated. Sixty iFDPs were compared for patient satisfaction and dental evaluation using ANOVA.

Results

For iFDP evaluation, patients generally provided more favorable ratings than dental experts, regardless of the workflow. ANOVA revealed no significant difference for overall satisfaction when comparing Test-1, Test-2, or Control, either for patients (f-ratio: 0.13; p = 0.876) or dentist (f-ratio: 1.55: p = 0.221). Secondary, patients clearly favored the digital impression workflows over the conventional approach (f-ratio: 14.57; p < 0.001). Overall, the 3Shape workflow (Test-1) received the highest scores for all analyses.

Conclusions

The different digital workflows demonstrated minor influence on the subjective and objective evaluation of the monolithic zirconium dioxide iFDPs in nonesthetic regions; however, the dentist may significantly increase patient satisfaction by choosing intraoral scanning instead of conventional impressions. The dentist has to consider individual patients’ needs to fulfill their expectations for a personalized solution.     

Registering Maxillomandibular Relation to Create a Virtual Patient Integrated with a Virtual Articulator for Complex Implant Rehabilitation: A Clinical Report

The virtual patient, a unique computer simulation of the patient's face, teeth, oral mucosa, and bone, provides an extraordinary mechanism for digital dental implant surgery planning and prosthetic design. However, the seamless registration of digital scans with functional information in the context of a virtual articulator remains a challenge. This report describes the treatment of a 47‐year‐old male with full‐mouth guided immediate implant placement and immediate loading of CAD/CAM interim prostheses. Utilizing a novel digital workflow, a multifactorial registration of the vertical dimension of occlusion, centric occlusion, and facebow record were completed digitally and paired within a digital articulator. Utilizing this innovative approach, a complex treatment plan and procedure was executed smoothly with a successful prosthetic outcome demonstrating good fit, occlusion, esthetics, and patient reported satisfaction.     

基于CT断层影像的下颌骨及下牙列三维几何学仿真

目的 进行基于CT断层影像的下颌骨及下牙列三维几何学仿真。方法 结合牙CT技术,采用交互式人机对话提取CT断层影像二维轮廓数据,应用美国PTC公司微机版Pro/Engineer和英国DELCAM公司POWERSHAPE等应用软件建立下颌骨及下牙列三维线框模型和实体模型。结果 得到了具有真实感的下颌骨及下牙列的三维实体模型,该模型能够进行三维显示,模型可编辑性强。结论 几何学仿真模型为快速原型和下颌骨及下牙列的力学仿真模型等进一步应用和研究打下了基础。本文采用的几何学仿真方法切实可行,在口腔颌面外科、骨科等领域有良好的应用前景。     

口内扫描数字化模型与硅橡胶制取石膏模型测量的对比研究

目的 研究应用口内扫描仪采集数字化牙颌模型与硅橡胶石膏模型测量之间的差异性.方法 选择口腔正畸科门诊初诊患者共30例,分别制取上下颌硅橡胶印模并灌制成超硬石膏模型;并用口内扫描仪（Trios,3Shape,丹麦）获取数字化模型并记录上下颌口内扫描时间.对口内数字化模型和石膏模型的牙齿宽度,牙弓长度、宽度,Spee＇s曲度进行测量,应用配对t检验分析各测量项目在两种模型测量的差异,独立样本t检验分析上下颌扫描时间、上下颌拥挤度的差异;重复测量计算组内相关系数（ICC）进行一致性检验.结果 两种模型上测量包含第一磨牙以前所有牙齿宽度,牙弓长度、宽度,Spee＇s曲度无统计学差异（P＞0.05）;所有重复测量ICC大于0.90.口内扫描时间上颌（411.9±162.2）s明显大于下颌（290.8±94.9）s,（P＜0.001）.结论 口内扫描获取的数字化模型与传统石膏模型测量之间无明显差异,有望在今后替代石膏模型.     

Orthodontic surgical treatment on an upper central dilacerated incisor in an adult patient

This study describes how a dilacerated upper central incisor was repositioned in the dental arch in an adult patient with proper surgical and orthodontic management avoiding use of prosthetic implants. The results were sustainable long term in both periodontal and aesthetic terms.     

应用LOM法制作-下颌骨及牙列的三维实体模型

目的 采用基于CT断层影像的下颌骨及牙列三维重建数据,利用快速成型中分层制造方法复制下颌骨及牙列。方法 利用Delcam公司（UK）软件将下颌骨及牙列三维重建的数据文件转换为STL文件,采用MagicsPR软件读入STL文件并进行检验与修补。制作下颌骨有牙列纸质实物模型,与下颌骨及牙列标本模型的几何相似性良好。结果 得下颌骨及下牙旬的快速原型模型。结论 下颌骨及牙列复制模型精度符合口腔修复中的要求,可在其计算机三维实体模型基础上进行牙列缺损的计算机辅助修复设计。     

Prosthetic Status and Prosthetic Need Among the Patients Attending Various Dental Institutes of Ahmedabad and Gandhinagar District, Gujarat

The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment form (1997). Prosthetic status and prosthetic treatment need was recorded. Out of 510, any type of Edentulousness was 322 (63 %). Among them, 254 (49.8 %) were partially edentulous while 68 (13.3 %) were completely edentulous. Only 69 (13 %) were having any prosthesis in upper arch while only 80 (16 %) were having any prosthesis in lower arch. Need for any type of prosthesis in upper and lower arch was 55 and 60 % in males and females, respectively. In lower social class group need of prosthesis in upper and lower arch was 62 and 63 %, respectively. It was found that prosthetic status and prosthetic treatment need increased with increase in age. Steps should be taken to overcome this disparity and more emphasis should be given to meet the felt need of the people through government and non government organizations to improve the oral health. The unmet prosthetic treatment need should be met to rehabilitate needy people so that their disability may be limited.     

A fully digital approach to fabricating a CAD-CAM ceramic crown to fit an existing removable partial denture

The use of a fully digital approach to fabricate an anatomic contour crown to fit an existing removable prosthesis allows the dentist and the dental laboratory technician to work efficiently in a digital environment. This report presents a series of patient treatments involving the fabrication of an anatomic contour monolithic zirconia crown to retrofit an existing removable partial denture. A complete digital workflow comprises an intraoral digital scan and computer-aided design and computer-aided manufacturing (CAD-CAM) technology.     

Dental arch morphology in south-east Asian adults with obstructive sleep apnoea: geometric morphometrics

Summary  The association between dental arch morphology and the aetiology of obstructive sleep apnoea (OSA) is not clear. To compare dental arch morphology in 108 Asian adults with and without 'OSA, overnight' hospital polysomnography was performed, and sleep reports were obtained for all subjects. Standardized digital photographs were also taken of the subjects' upper and lower study models. Using 25 homologous landmarks, mean OSA and control dental arch configurations were computed, and subjected to finite-element morphometry (FEM), t -tests and principal components analysis (PCA). Mean upper and lower OSA dental arch morphologies were statistically different from respective Control upper and lower arch morphologies ( P  < 0·05). FEM of the upper arch indicated that the mean OSA configuration was 7–11% narrower in the transverse plane in the incisor and canine regions when compared with the control configuration, and inter-landmark analysis (ILA) confirmed this finding. FEM for the lower arch indicated that the mean OSA configuration was 10–11% narrower in the antero-posterior plane in the pre-molar and molar regions, and confirmed by ILA. Using PCA, significant differences were also found between the two groups in the lower arch using the first two eigenvalues, which accounted for 90% of the total shape change ( P  < 0·001). Supporting their role as aetiological factors, size and shape differences in dental arch morphology are found in patients with OSA.     

Dental arch dimensions in the mixed dentition: a study of Brazilian children from 9 to 12 years of age

Objective

This study evaluated dental arch dimensional changes of Brazilian children.

Material and methods

Dental casts were taken from 66 children (29 males; 37 females) with normal occlusion selected among 1,687 students from public and private schools aged 9, 10, 11 and 12 years, according to the following criteria: Class I canine and molar relationships; well-aligned upper and lower dental arches; mixed dentition; good facial symmetry; no previous orthodontic treatment. Dental arch dimensions were taken by one examiner using the Korkhaus’ compass and a digital pachymeter. ANOVA test was applied to compare the arch dimensions at the different ages and the t-test was used to compare the arch dimensions of male and female subjects. Arch forms were compared by means of chi-square tests.

Results

Only the maxillary anterior segment length showed a statistically significant increase from 10 to 12 years of age. Males had a significantly larger maxillary depth than females at the age range evaluated. The predominant dental arch form found was elliptical.

Conclusion

In the studied age range, anterior maxillary length increased from 10 to 12 years of age, males had larger maxillary depth than females and the predominant arch form was elliptical.     

Guided Osteotomy and Guided Autotransplantation for Treatment of Severely Impacted Teeth: A Proof-of-Concept Report

IntroductionThe aim was to present a novel surgical technique using virtually preplanned 3-dimensional (3D)-printed templates for guided osteotomies. These were to ensure atraumatic uncovering of a severely impacted donor tooth including guided drilling of the recipient alveolus followed by a secure autotransplantation procedure.MethodsThis report presents an autotransplantation procedure of a 14-year-old patient with a severely impacted second premolar and extensive contact to the roots of the adjacent teeth and the inferior alveolar nerve. Autotransplantation of the impacted premolar was virtually performed using modified methods from guided implant surgery in order to prefabricate 3D-printed templates with the aid of a fully digital workflow.ResultsSatisfactory treatment could be achieved using surgical templates for guided osteotomies of the surgical access, guided drilling of the recipient site, and occlusal reference template ensuring autotransplantation in the appropriate 3D location of the graft. An atraumatic approach could be ensured with an extraoral time of 46 seconds by 1 fitting attempt; no injuries or altered sensation of the inferior alveolar nerve were present. A vital natural tooth could be observed.ConclusionsThis innovative technique uses for the first time a fully implemented digital workflow for guided osteotomies, guided drilling, and guided autotransplantation of a severely impacted tooth. 3D-printed templates could ensure a guided atraumatic approach and facilitate highly complex treatments by virtually implementing recommended guidelines in future autotransplantations.     

Fully Digital Workflow with Magnetically Connected Guides for Full‐Arch Implant Rehabilitation Following Guided Alveolar Ridge Reduction

This technique report describes a fully digital workflow in which two surgical guides (i.e. one for alveolar bone reduction and the other for implant placement) are magnetically connected to ensure stability during full‐arch implant surgery following guided bone reduction. Digital prosthesis design as well as virtual bone reduction and implant planning are developed from the superimposition of facial, intraoral and CBCT scans. With this technique, different surgical guides and interim poly(methylmethacrylate) (PMMA) fixed prosthesis are precisely connected with magnets after being digitally designed and 3D‐printed. As a result, such magnetic connection allows for satisfactory stability of the implant surgical guide, as well as of the interim fixed PMMA fixed prosthesis during capture of screw‐retained abutments.     

Comprehensive virtual orthognathic planning concept in surgery-first patients

The surgery-first concept is becoming increasingly popular in orthognathic surgery since it offers major advantages such as a reduction of treatment duration and an increase in patient satisfaction by eliminating phases of presurgical orthodontic decompensation. Here, we present a novel interdisciplinary pathway of a fully virtual orthodontic-surgical planning concept in a surgery-first setting using a 3D-printed cutting guide and a customised maxillary implant for the Le Fort I osteotomy as well as a CAD/CAM-based stereolithographic final splint. Patient data from cone-beam computed tomography of the skull and a full arch dental scan were processed using the OnyxCeph^3TM software (Image Instruments). A mutual computer-aided surgical simulation was conducted by the orthodontist and the oral and maxillofacial surgeon to determine the three-dimensional maxillary and mandibular movements. In a separate virtual planning session, the surgeon designed a customised maxillary guide and implant for precise intraoperative transfer (Geomagic Freeform Plus software, 3DSystems). A 3D-printed CAD/CAM-based final splint was fabricated by the orthodontist and used for accurate mandibular repositioning. We established a comprehensive virtual interdisciplinary orthognathic workflow and successfully applied this concept with a high level of accuracy in a series of surgery-first patients with different types of dentofacial anomalies. This novel fully computer-based pathway offers a high potential to improve the outcomes of orthognathic surgery and reduce total treatment time in the management of the orthognathic patient.     

完全性唇腭裂两种治疗模式的初步探讨

目的 探讨两种治疗模式对上颌牙槽骨的生长发育及腭咽闭合的影响。方法 将124例腭裂分为A组（63例），用Latham或Millard法，B组（61例）用早期软腭粘接法，测量124例唇腭裂上颌石膏模型，测量X线片牙槽裂区骨桥。结果 A组牙弓横径较B组大；A组在双侧唇腭裂，上牙弓的前后径小于B组，但随患者年龄增长，两组差别逐渐减小；A组在唇腭裂单侧和双侧牙槽裂区分别有63.0%和83.3%的骨桥生长；A组和B组分别有15.9%和35.2%的患者需要咽瓣手术。结论 A组稳定的上牙弓能对抗唇肌的压迫。维持牙弓的宽度，但A组9岁以后双侧唇腭裂牙弓的前后径还需进一步的追踪。A组需要咽瓣手术的病例较B组少。