Treatment of an Edentulous Patient with CAD/CAM Technology: A Clinical Report

CAD/CAM (computer-aided design/computer-aided manufacturing) technology with large-scale industrial applications has been developed and used over the last 3 decades. Implant Innovations, Inc. (Palm Beach Gardens, FL), has recently introduced a version of this technology for use in implant restorative dentistry. Different software programs were written to design and machine individual implant abutments and bar-type frameworks. This report provides a literature review of CAD/CAM technology in dentistry and describes the treatment of one edentulous patient restored with individual implant abutments and conventional cemented fixed partial dentures in the edentulous maxilla and a fixed, screw-retained prosthesis that replaced the missing mandibular teeth. The abutments were made using The Encode Restorative System; the mandibular framework was made with a CAM StructSURE Precision Milled Bar. The benefits and limitations of this technology are also discussed. Additional clinical and laboratory studies are needed to further validate this technology.     

A Digital Approach to Retrofitting a Post and Core Restoration to an Existing Crown

One problem that may arise in full‐coverage restorations is clinical crown fracture. Fracture of an endodontically treated and crowned tooth in the esthetic zone may be embarrassing to both the patient and clinician. If a completely sound margin and at least 2 mm of coronal structure remain, a fractured tooth may possibly be retreated by a repair. Several methods have been introduced to reproduce the original contour of the tooth for retrofitting an existing crown. If an existing crown is used as a template, excessive core material may remain over the margin, as loading the proper amount of core material is difficult, and making vent holes on the existing crown is not feasible. This article presents a repair technique to reuse an existing crown with computer‐aided design and computer‐aided manufacturing (CAD/CAM) technology. By using a milled poly(methylmethacrylate) matrix, the mentioned limitations are eliminated, and the original contour of the tooth can be effectively restored with minimal intervention. As an existing crown is reused, the issues of additional time and cost for repreparation, reimpression, and new crown are eliminated.     

椅旁CAD/CAM牙科修复系统的历史与临床应用现状

自1985年Sirona牙科系统问世以来,CEREC椅旁CAD/CAM修复系统逐渐获得牙科医生的认可和青睐。本文回顾了CEREC系统的发展简史,临床应用,治疗方案,用于制作各种修复体的材料以及患者的满意度、接受程度等。CEREC3D系统是目前世界上唯一的椅旁牙科修复系统。患者1次就诊,即可采用100%生物相容性全瓷材料完成嵌体、高嵌体、贴面冠、全冠、3/4冠等各种修复体的制作,其功能和美观程度堪与天然釉质媲美。CEREC3D系统的用户界面及程序设计对熟悉传统制作方式的牙科医生极为有利,多数牙科医生认为,CEREC3D系统优于传统制作方法,因为修复体的设计和制作完全自动化,不受口腔操作范围有限的束缚。CEREC3D系统已被临床证明是当今牙科修复的好助手,已在日常工作中显示出其高效性和有效性。     

Development of gingival esthetics in the edentulous patient with immediately loaded, single-stage, implant-supported fixed prostheses: a clinical report

Many clinicians have reported on the success of immediately loaded implants supporting a bilaterally stabilized provisional fixed prosthesis. This protocol offers several advantages, including increased masticatory function, minimized uncontrolled transmucosal loading through cross-arch stabilization, improvement of psychologic well-being, and reduction in treatment time. However, the development and maintenance of proper dentogingival esthetics in the edentulous maxilla presents substantial challenges for the implant team. This article presents the specific pretreatment diagnostic requirements for immediate loading of single-stage implants and demonstrates a new surgical technique, followed by appropriate prosthodontic management, to develop an optimal gingival profile with interdental papillae surrounding a natural-looking dentition. One hundred fifty-one ITI implants were placed into 22 dental arches and immediately loaded with a 1-piece fixed prosthesis. The results of this technique over the last 5 years are presented.     

Clinical fit of four‐unit zirconia posterior fixed dental prostheses

The objective of this clinical study was to assess the internal and marginal accuracy of computer‐aided design/computer‐aided manufacturing (CAD/CAM)‐generated four‐unit all‐ceramic posterior fixed dental prostheses (FDPs). The data were compared with the results of three‐unit metal‐ceramic and all‐ceramic FDPs that were obtained in a previous study. Twenty‐four patients were provided with all‐ceramic posterior four‐unit FDPs made from semisintered blank zirconia material. Prior to definitive insertion the accuracy was evaluated using a replica technique with a light body silicone that was stabilized with a heavy body material. The replica samples were examined using microscopy. The median marginal gap of the 24 four‐unit FDPs was 77 μm. The median gap widths were 87 μm at the midaxial wall, 167 μm at the axio‐occlusal transition of the abutments, and 170 μm at centro‐occlusal location. Although the marginal accuracy of the four‐unit FDPs differed significantly from that of the three‐unit metal‐ceramic FDPs (median 54 μm), the values obtained were clinically satisfactory and showed that semisintered zirconia blanks could be used for the fabrication of four‐unit FDPs.     

自主研发CAD/CAM种植导板制作系统在无牙颌种植修复中的临床应用研究

目的评价自主研发CAD/CAM种植导板制作系统在无牙颌种植修复中的临床应用。方法选择5例单颌无牙颌患者。锥形束CT扫描采集数据,导入自主研发种植导板软件进行导板的数字化设计,快速成型机制作种植导板。在导板引导下进行无牙颌种植手术,植入ITI种植体。3个月后复查,行种植义齿修复。术后定期随访。结果为5例患者制作完成丙烯酸树脂CAD/CAM种植导板,在导板引导下采用不翻瓣术式共植入38枚ITI种植体,初期稳定性良好,术后反应小。术后3个月骨结合良好,仅1枚种植体脱落。5例患者均采用固定式种植修复,术后6个月及1年的随访显示,修复体功能和美观良好。结论该自主研发的CAD/CAM种植导板制作系统应用于无牙颌种植手术,能实现术前精确设计和术中精确控制种植体位置,减少了手术创伤和术后并发症,取得良好的种植修复效果。     

Fabrication systems for restorations and fixed dental prostheses made of titanium and titanium alloys

PurposeIn recent years, the application of restorations and fixed dental prostheses to molars by computer-aided design-computer-aided manufacturing (CAD/CAM) with composite resin has been increasing. Titanium and titanium alloy having a high tissue affinity and good biocompatibility are suitable for cases where CAD/CAM fabrications are inadequate, such as allergic reaction to metal. Many studies have reported methods of production with titanium and titanium alloys. The purpose of this review is to survey the clinical application of titanium and titanium alloy restorations and fixed dental prostheses with various fabrication systems.Study selectionA literature search in PubMed was performed for various fabrication systems of titanium and titanium alloy from 2010 through 2019. The search keywords were “titanium”, “titanium alloy”, “CAD/CAM”, “cast”, “fabrication system”, “marginal gap”, “internal gap”, and “clinical performance”. Only relevant studies are summarized and discussed in this review.ResultsWith any fabrication system, titanium and titanium alloy restorations and fixed dental prostheses fabricated with various systems were within the clinically acceptable ranges of marginal gap and internal fit. Additionally, these restorations were considered to have less effect on the periodontal issues. Although metal–ceramic restoration has clinical performance problems, such as ceramic fracture, fabrications with only titanium and titanium alloy were reported to have good clinical performance.ConclusionsRegardless of the fabrication system, titanium and titanium alloy restorations and fixed dental prostheses can be applied clinically. Titanium and titanium alloys are thought to be a promising alternative to the dental metals currently used.     

CAD/CAM树脂桥联合数字化导板在无牙颌即刻负荷中的应用研究

目的:研究和评估CAD/CAM树脂桥联合数字化导板在无牙颌患者即刻负荷中的应用效果.方法:选择30例无牙颌患者,共356枚植体,662颗冠,其中单颌9例,全口21例;均应用导板辅助外科植入,CAD/CAM树脂桥进行即刻负荷,在戴入后即刻、1个月、3个月进行效果评估,并统计种植体周围黏膜炎发生率、树脂桥的折裂率以及植入时和永久修复前的植体动度(ISQ).结果:评估期间30例患者均无植体脱落现象.1个月和3个月的黏膜炎发生率分别为2.8％和3.3％,且集中在1例患者中;树脂桥的折裂情况在1个月时无发生,3个月时发生率1.5％,且集中在2例患者中.上颌植体植入时和永久修复前的平均ISQ值分别为62.70±1.07和81.81±1.52,下颌植体植入时和永久修复前的平均ISQ值分别为67.65±0.96和83.71±0.90,差异有统计学意义(P＜0.0001).结论:CAD/CAM树脂桥联合数字化导板,是一种可重复性高、临床效果好的无牙颌即刻负荷的临床诊疗新方法,值得推广和应用.     

数字化口腔修复（3）-CAD／CAM二氧化锆钉MOD高嵌体修复（附病例报告）

目的：观察CAD／CAM二氧化锆钉MOD高嵌体修复后牙残冠的临床疗效。方法：临床病例为3颗大面积缺损的磨牙残冠患者,经过完善的根管治疗后,采用CAD／CAM二氧化锆钉MOD高嵌体修复,按照改良的USPHS标准分别进行6个月和1年的临床疗效评价。结果：各时段复查结果表明：3颗患牙无脱落,折断、劈裂等不良现象。临床指标均达到A级。结论：CAD／CAM二氧化锆钉MOD高嵌体修复后牙牙体大面积缺损具有良好的临床效果,远期疗效有待进一步观察。     

数字化口腔修复（19）--激光切龈与CAD／CAM全瓷冠美学修复（附病例报告）

目的：观察二极管激光修整前牙牙龈形态、龈沟深度及CEREC?椅旁计算机辅助设计与制造（ computer aided design／computer aided manufacturing,CAD／CAM）全瓷冠美学修复的临床效果。方法：前牙12、21、22牙体缺损患者1例,二极管激光修整前牙牙龈形态、龈沟深度,并用CEREC?椅旁CAD／CAM行全瓷冠美学修复。6个月后采用改良USPHS标准对其短期的临床疗效进行评估。结果：二极管激光修整牙龈1周后开始呈粉红,质地韧,形态和龈沟深度协调;修复6个月后全瓷冠完整无折裂,未见继发龋;修复体边缘密合,固位、邻接良好,颜色美观。结论：激光切龈方法精确,创伤小,出血少,视野清晰,愈合快,患者容易接受。     

Clinical experiences of implant-supported prostheses with laser-welded titanium frameworks in the partially edentulous jaw: a 5-year follow-up study

Background: Titanium frameworks have been used in the endentulous implant patient for the last 10 years. However, knowledge of titanium frameworks for the partially dentate patient is limited. Purpose: To report the 5-year clinical performance of implant-supported prostheses with laser-welded titanium frameworks in the partially edentulous jaw. Materials and Methods: A consecutive group of 383 partially edentulous patients were, on a routine basis, provided with fixed partial prostheses supported by Brånemark implants in the mandible or maxilla. Besides conventional frameworks in cast gold alloy, 58 patients were provided with titanium frameworks with three different veneering techniques, and clinical and radiographic 5-year data were collected for this group. Results: The overall cumulative survival rate was 95.6% for titanium-framework prostheses and 93.6% for implants. Average bone loss during the follow-up period was 0.4 mm. The most common complications were minor veneering fractures. Loose and fractured implant screw components were fewer than 2%. An observation was that patients on medications for cardiovascular problems may lose more implants than others (p <.05). Conclusions: The clinical performance of prostheses with implant-supported laser-welded titanium frameworks was similar to that reported for conventional cast frames in partially edentulous jaws. Low-fusing porcelain veneers also showed clinical performance comparable to that reported for conventional porcelain-fused-to-metal techniques.     

数字化口腔修复（23）--激光脱敏后的CAD／CAM全瓷冠修复（附病例报告）

目的：观察二极管激光活髓牙脱敏后的CAD／CAM全瓷冠修复效果。方法：对1例13-23／33-43活髓牙烤瓷联冠修复患者,伴有冷热刺激敏感,牙龈萎缩,边缘不密合及颜色不协调,应用CEREC?椅旁CAD／CAM全瓷冠修复,二极管激光辅助活髓牙牙本质脱敏。3个月后采用改良USPHS标准对其临床疗效进行评价。结果：椅旁CAD／CAM二矽酸锂玻璃陶瓷全冠修复体外形颜色美观,边缘密合,粘接、固位良好,冷热刺激过敏症状消除。牙龈健康,形态正常及探诊无出血。结论：半导体激光可以有效减轻和消除牙本质过敏症状。     

Prosthodontic management of edentulous patient with limited oral access using implant-supported prostheses: a clinical report

Limited oral access presents a unique challenge to prosthodontic treatment. An edentulous patient who developed microstomia after a maxillary lip resection is presented. The clinical procedure and the rationale for the treatment approach using implanted-supported overdentures are discussed.     

Restoring function and esthetics in a patient with amelogenesis imperfecta: a clinical report

This clinical report describes the prosthodontic treatment for an 18-year-old man diagnosed with amelogenesis imperfecta. The aim of treatment was to reduce dental sensitivity and to restore esthetics and masticatory function. Metal-ceramic fixed partial dentures were placed on posterior teeth to modify the occlusion, and porcelain laminate veneers were placed to improve the esthetics of the maxillary anterior teeth. Clinical examination 12 months after treatment revealed no evidence of disorders associated with the restored teeth or their supporting structures.     

The use of TMJ Concepts prostheses to reconstruct patients with major temporomandibular joint and mandibular defects

Temporomandibular joint (TMJ) reconstruction may be required in complex cases in which there are additional mandibular or zygomatic arch defects. The reconstructive options include autogenous tissue, alloplastic material, or combinations of these. The authors describe 4 cases in which TMJ reconstruction was performed with TMJ Concepts customized joint prostheses. The prosthetic components were designed to restore major defects in the zygomatic arch and the mandibular ramus and body, including one case in which the mandibular component was used to restore total mandibular continuity. The prosthetic components used in these cases provided excellent anatomical reconstruction, and were a viable treatment option in cases in which the pathological process made autogenous grafts unsuitable. The prostheses have been functioning for up to 6 years. In one case a revision operation was required because the lack of a pterygomasseteric sling resulted in the condyle dropping out of the fossa. The authors’ clinical experience with these cases suggests that a customized prosthesis combined with TMJ reconstruction can be a reliable treatment alternative for bridging complex, major maxillo-mandibular defects.     

Step-by-step full mouth rehabilitation of a nasopharyngeal carcinoma patient with tooth and implant-supported prostheses: A clinical report

This clinical report presents a 46-year-old man diagnosed with nasopharyngeal carcinoma with the chief complaint of masticatory and speech deficiency because of radiation therapy. After a period of controlling post radiation caries, the patient was rehabilitated with tooth and implant supported metal ceramic restorations following surgical and endodontic intervention.