An overview of the CEREC 3D CAD/CAM system

Computer-aided design/computer-aided manufacture (CAD/CAM) technology has made steady inroads into the practice of dentistry. The CEREC CAD/CAM system can be used chairside to fabricate porcelain and composite inlays, onlays, and crowns and porcelain veneers. The latest incarnation of the CEREC system is the CEREC 3D, which provides a versatile, relatively simple, user-friendly method for fabricating esthetic restorations chairside without involving a dental laboratory. CEREC 3D may be the system that allows the average general dentist to provide chairside porcelain restorations during single-visit appointments, eliminating the need for an elastomeric impression or an interim restoration as well as the expense of a laboratory fee.     

椅旁CAD/CAM(CEREC AC~(TM))全瓷修复的临床回顾性研究

目的评价椅旁CAD/CAM系统(CEREC AC~(TM))进行全瓷修复的临床效果。方法针对619例患者的667颗各类牙体缺损患牙采用西诺德的瓷睿刻系统(CEREC AC~(TM))进行临床即刻椅旁CAD/CAM全瓷修复,1年后对597例患者的603颗瓷睿刻修复体进行临床效果评价。采用USPHS修订版指标检查,包括美观——解剖形态、颜色匹配、边缘变色、表面质地;功能——边缘吻合性、磨耗(邻接、动静态咬合关系);生物学性能——牙髓活力、继发龋。结果 1年的随访结果发现,临床存留率达到95.11%,失败病例中修复体折裂占比为83%。93%的全瓷修复体表现出较高的美学评分,82%的修复体保持了较好的功能评分,而100%的修复体未见生物学并发症。结论不同牙体缺损患牙的瓷睿刻椅旁CAD/CAM全瓷修复,可获得理想的临床效果,但仍需长期随访。     

CAD/CAM ceramic restorations in the operatory and laboratory

Computer assisted design/computer assisted machining (CAD/CAM) technology has received considerable clinical and research interest from modern dental practices as a means of delivering all-ceramic restorations. The CEREC, System offers CAD/CAM dental technology designed for clinical use by dentists, as well as a separate system designed for dental laboratory technicians. The CEREC 3 system is indicated for dental operatory applications, and the CEREC inLab, system is indicated for dental laboratory applications. Although both systems rely on similar CAD/CAM technology, several significant differences exist in the processing techniques involved, restorative materials used, and types of restoration provided.     

计算机辅助设计和制作数字椅旁全瓷修复系统的研究进展及应用

计算机辅助设计和制作数字椅旁全瓷修复系统(CERECCAD/CAM)作为一种快捷美观的修复方式,在临床应用日趋广泛。本文就数字椅旁全瓷修复系统的发展现状、配套材料以及临床应用研究作一综述。     

Clinical performance of CEREC ceramic inlays: a systematic review.

OBJECTIVE: This systematic review of clinical trials seeks to identify the clinical performance of intra-coronal CEREC restorations luted with an adhesive composite technique. The focus of the review is to establish the survival rate of these restorations and to identify the factors that may cause them to fail. METHOD: A comprehensive literature search was undertaken, spanning from the year of introduction of the technology--1986 to 1997. This review identifies universal indicators of the clinical performance of intra-coronal CEREC restorations luted with an adhesive composite technique. Throughout the critical appraisal, each individual study was analysed identifying the aims, the methodology and materials used and the results obtained. RESULTS: 29 clinical reports were identified in the search. The systematic analysis reduced the focus of review to 15 studies. The data available establishes ceramic intra-coronal restorations machined by the CEREC system as a clinically successful restorative method with a mean survival rate of 97.4% over a period of 4.2 years. The review also highlights the reasons and the rates of failure for this type of restoration. The predominant reasons for failures are fracture of the ceramic, fracture of the supporting tooth, postoperative hypersensitivity and wear of the interface lute. SIGNIFICANCE: Machinable ceramics, as used by the CEREC system provide a useful restoration with a high success rate. These restorations are color stable and wear at a clinically acceptable rate. Wear of the luting composite on occlusal surfaces leads to the phenomenon of submargination. Ceramic fracture, wear at the interface and post-operative hypersensitivity remain a problem which require further investigation.     

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。     

CEREC椅旁CAD/CAM诊室技术25年的研究进展

25年来,椅旁计算机辅助设计和计算机辅助制作(CAD/CAM)技术在口腔诊室中的应用不断发展,口腔材料的改进也加速了CAD/CAM技术的革新,这些使得口腔医生几乎能迅速、精确地为每位患者提供高品质、高美观的修复体。基于CAD/CAM技术在口腔科应用的不断增加,制造商对CEREC系统的硬件、软件和材料进行了大量改进,口腔医生可以在诊室内不受工艺流程的干扰制作出技工室水平的修复体。本文就CEREC椅旁CAD/CAM系统支持材料及AC系统创新发展作一综述。     

80件CEREC3全瓷修复体的临床效果回顾分析

目的探讨应用数字椅旁全瓷修复系统（CEREC3）进行椅旁即刻全瓷修复的临床效果。方法采用数字椅旁全瓷修复系统（CEREC3）共完成75例患者的全瓷修复体80件。追踪观察1.0～1.5年,询问患者对全瓷修复的主观感受,记录全瓷修复体的变化等。回顾分析80件全瓷修复的临床疗效。结果患者对CEREC3全瓷修复体的主观评价满意率为95.00%（76/80）,崩瓷率为3.75%（3/80）。结论采用CEREC3,能制作出高质量并且具有天然牙色的全瓷修复体,方便快捷,临床效果满意。     

Scanning electron microscope evaluation of CEREC II and CEREC III inlays

In response to an increased public demand for esthetic restorations, dentists are using computer-aided design/computer-aided manufacture (CAD/CAM) technology to fabricate inlay/onlay, crown, and laminate veneers. This study evaluated the fit at the gingival margin of surface inlay restorations milled by the CEREC II as well as the more recently developed CEREC III. The marginal fit of inlays milled by the CEREC III was more accurate than the fit of those milled by the CEREC II, although both were within the ADA specifications of 50 micro.     

The clinical performance of CAD/CAM-generated composite inlays

BACKGROUND: The authors conducted a study to evaluate the longitudinal clinical performance of a resin-based composite (Paradigm, 3M ESPE, St. Paul, Minn.) for computer-aided design/computer-aided manufacturing (CAD/CAM)-generated adhesive inlays. METHODS: The researchers used a CAD/CAM unit (CEREC 2, Sirona Dental Systems, Bensheim Germany) to fabricate 40 porcelain (Vita Mark II, Vita Zahnfabrik, Bad S?ckingen, Germany) and 40 resin-based composite (Paradigm, 3M ESPE) inlays. Both restorative materials were cemented with a total-etch technique using Single Bond dental adhesive (3M ESPE) and a dual-cured resin cement (RelyX ARC Adhesive Resin Cement, 3M ESPE). Two examiners evaluated the inlays using modified U.S. Public Health Service (PHS) criteria at six months, one year, two years and three years. RESULTS: No sensitivity was reported for either material at any recall period. There was no significant difference between the two materials relative to margin adaptation at three years. Margin adaptation initially was very good for both materials, with an increase in margin detection due to apparent wear of the resin-based composite luting agent. There was a significant difference in color match between the two materials at three years, with 91.4 percent of the resin-based composite inlays and 58.8 percent of the porcelain inlays rated Alfa. CONCLUSIONS AND CLINICAL IMPLICATIONS: The resin-based composite inlays had a significantly better color match at three years than did the porcelain inlays. Resin-based composite CAD/CAM inlays performed as well as porcelain CAD/CAM inlays after three years of clinical service.     

CEREC AC全瓷修复系统的临床效果研究

目的 探讨椅旁CAD/CAM CEREC AC全瓷修复系统在牙体缺损修复中的应用和效果。方法 观察自2012年8月至2014年7月期间,采用CEREC AC全瓷修复系统所修复的70个病例,其中瓷嵌体10颗,全瓷冠60颗,由同一医生利用改良的美国公共健康协会修订标准（USPHS）对修复后6个月及12个月修复体的外形、边缘适合性、颜色匹配性、边缘染色、固位、修复后敏感性、牙龈健康及继发龋等方面进行评价。结果 70件修复体在观察期内保存完整,边缘密合,无明显松动、脱落、折断、继发龋、明显的牙齿敏感以及牙龈炎症等不良现象发生,修复后6个月及12个月的临床评价结果对比无统计学差异（P>0.05）。结论 CEREC AC全瓷修复系统可以高效地应用于牙体缺损的修复治疗,基于此方法制作出的修复体能达到令人满意的临床效果。     

可切削复合树脂材料磨损性能的研究

目的：研究可切削复合树脂材料与天然牙釉质磨损性能的匹配情况。方法在微摩擦磨损实验机上,模拟口腔力学和化学环境,以三种新型的可切削复合树脂材料( Upcera 复合树脂、Lava Ultimate、High-Class)为研究对象,天然牙釉质为对磨物。实验前,用激光共聚焦显微镜测试试件表面粗糙度Sa,实验后,激光共聚焦下观察可切削复合树脂试件的磨斑形貌、测量其磨斑面积及对磨物牙釉质的磨斑宽度,扫描电镜下观察试件磨斑的微观形貌。采用单因素方差分析进行统计学分析。结果牙釉质的磨斑面积和磨斑宽度大于其他三种可切削复合树脂材料(P<0.05)。结论与牙釉质相比,三种可切削复合树脂具有更佳的耐磨性及较低的对磨物磨损。     

Materials for chairside CAD/CAM restorations

Chairside computer-aided design/computer-aided manufacturing (CAD/CAM) systems have become considerably more accurate, efficient, and prevalent as the technology has evolved in the past 25 years. The initial restorative material option for chairside CAD/CAM restorations was limited to ceramic blocks. Restorative material options have multiplied and now include esthetic ceramics, high-strength ceramics, and composite materials for both definitive and temporary restoration applications. This article will review current materials available for chairside CAD/CAM restorations.     

In vivo wear of CAD-CAM composite versus lithium disilicate full coverage first-molar restorations: a pilot study over 2 years

Objectives

To present a digital approach to measure and compare material wear behavior of antagonistic first molar restorations made of an experimental CAD/CAM composite (COMP) and lithium disilicate ceramic (LS2) in patients with reconstructed vertical dimension of occlusion (VDO) after generalized hard tissue loss.

Methods

A total of 12 patients underwent complete full jaw rehabilitation with full occlusal coverage restorations made either of COMP or LS2. The first molar restorations (n = 48) were chosen for wear examination. At annual recall appointments, polyether impressions were taken, and resulting plaster casts were digitalized using a laboratory scanner. Mean observation period was 371 days for first and 769 days for second year. The resulting 96 datasets were analyzed by superimposition of 3-D datasets using an iterative best-fit method. Based on the superimposition data, the wear rates of the occlusal contact areas (OCAs) were calculated.

Results

For antagonistic restorations made of COMP, the average wear rate was 24.8 ± 13.3 μm/month, while for LS2, it was 9.5 ± 4.3 μm/month in first year, with significant differences (p < 0.0001) between the materials. In second year, monthly wear rates decreased significantly for both materials: COMP (16.2 ± 10.7 μm/month) and LS2 (5.5 ± 3.3 μm/month). Statistical comparison between wear time showed significant differences for both materials: COMP p < 0.037 and LS2 p < 0.001. A logarithmic fit (COMP R² = 0.081; LS2 R² = 0.038) of the data was calculated to estimate the wear progression.

Significance

In patients with reconstructed VDO, restorations made of LS2 show a more stable wear behavior than ones out of experimental CAD/CAM composite. In cases of complete rehabilitation, load bearing CAD/CAM-composite restorations should be critically considered for application due to their occlusal wear behavior. However, when choosing a restorative material, not only the functional occlusal stability should be taken into account but also the prospect of minimally invasive treatment with maximum preservation of natural tooth structures.

     

CADCAM瓷贴面修复的临床效果探析

[摘要] 目的 评价CAD/CAM全瓷贴面修复前牙的临床效果。方法 选择98颗前牙,采用CEREC的椅旁CAD/CAM修复系统及IPS e.max CAD瓷块即刻完成修复体并粘结。参照改良Ryge评价方法,对临床使用1周、6个月、12个月、24个月的贴面在颜色匹配、瓷表面完整度、边缘染色、边缘适应性、术后敏感、牙龈健康状况、继发龋方面进行临床评价。结果 CAD/CAM全瓷贴面在这些方面的临床评级,90%以上达到A级。结论 用CEREC的椅旁CAD/CAM修复系统及IPS e.max CAD瓷块完成的贴面临床效果良好可靠。     

Effect of Camera Angulation on Adaptation of CAD/CAM Restorations

Purpose: A significant concern with computer-assisted design/computer-assisted manufacturing (CAD/CAM)-produced prostheses is the accuracy of adaptation of the restoration to the preparation. The objective of this study is to determine the effect of operator-controlled camera misalignment on restoration adaptation.
Materials and Methods: A CEREC 2 CAD/CAM unit (Sirona Dental Systems, Bensheim, Germany) was used to capture the optical impressions and machine the restorations. A Class I preparation was used as the standard preparation for optical impressions. Camera angles along the mesio-distal and buccolingual alignment were varied from the ideal orientation. Occlusal marginal gaps and sample height, width, and length were measured and compared to preparation dimensions. For clinical correlation, clinicians were asked to take optical impressions of mesio-occlusal preparations (Class II) on all four second molar sites, using a patient simulator. On the adjacent first molar occlusal surfaces, a preparation was machined such that camera angulation could be calculated from information taken from the optical impression. Degree of tilt and plane of tilt were compared to the optimum camera positions for those preparations.
Results: One-way analysis of variance and Dunnett C post hoc testing (α= 0.01) revealed little significant degradation in fit with camera angulation. Only the apical length fit was significantly degraded by excessive angulation. The CEREC 2 CAD/CAM system was found to be relatively insensitive to operator-induced errors attributable to camera misalignments of less than 5 degrees in either the buccolingual or the mesiodistal plane. The average camera tilt error generated by clinicians for all sites was 1.98 ± 1.17 degrees.
CLINICAL SIGNIFICANCE
It is unlikely that camera misalignment is a major source of error during the fabrication of simplistic CEREC 2 CAD/CAM restorations.     

用于CEREC II型系统的电镀金刚石磨盘及切针的加工工艺

目的 :研制用于CERECII型计算机辅助设计与制作 (CAD/CAM )系统的电镀金刚石磨盘及切针 ,以替代进口。方法 :通过电镀工艺使金刚石磨粒和镍共沉积于不锈钢基体的表面从而形成超硬材料复合镀层的方法 ,加工金刚石磨盘和切针 ,在CERECII型CAD/CAM系统上试用并与进口产品进行磨削性能的初步对比。结果 :与进口产品相比 ,所加工的电镀金刚石磨盘及切针在磨削性能和耐用度方面无明显差异。结论 :采用的电镀工艺简单可行 ,加工的金刚石磨盘和切针可用于CERECII型CAD/CAM系统。     

Evaluation of the marginal seal of CEREC 3D restorations using two different luting agents

This in vitro study used two resin cements to evaluate the microleakage of CEREC 3D restorations. An mesio-occluso-distal-lingual (MODL) onlay preparation was placed on an ivorine premolar tooth. Sixty elastomeric impressions of this preparation were used to fabricate resin dies. Imaging propellant was applied to the resin dies. Optical impressions were taken with the CEREC 3 and the CEREC 3D software and used to design and mill 60 onlays. The reliability coefficient was alpha = 0.76 with an examiner agreement rate of 96.4%. Restorations cemented with posterior composite demonstrated a mean microleakage value of 1.46 mm (SD+/- 1.64); by contrast, those restored with dual-cure cement reported a mean microleakage value of 0.21 mm (SD+/-0.57). The difference in microleakage was very highly significant (alpha = 0.001). Posterior composite CEREC 3D restorations cemented with the dual-cure cement showed significantly less microleakage compared to those cemented with posterior composite.     

Margin gap size of ceramic inlays using second-generation CAD/CAM equipment

OBJECTIVE: The goal of this study was to determine if the fit of second-generation computer-assisted design/computer-assisted manufacturing (CAD/CAM) (CEREC 2, Sirona Dental Systems, Bensheim, Germany) inlays within Class II cavity preparations were within the range of 50 to 100 microns and were equal or better to CEREC 1 inlays. MATERIALS AND METHODS: Extracted human molars free of surface defects and caries were prepared with standard mesio-occlusodistal cavity preparations. Ceramic inlays were fabricated with CEREC 2 CAD/CAM equipment and seated into cavity preparations. Digital images were captured at 100 times magnification. Marginal gaps were measured with an image analysis program. For each restoration, gaps were measured at 12 locations along interproximal margins and 10 locations along occlusal margins. RESULTS: No difficulty occurred in seating any of the milled inlays. Average marginal gaps for occlusal (59 +/- 35 microns) and interproximal (97 +/- 66 microns) margins were statistically different (t-test, p < or = .01). Average marginal gap for all sites combined was 80 +/- 57 microns. Marginal gap widths were smaller than those obtained from a similar study done earlier with the CEREC 1 unit for occlusal (89 +/- 65 microns) and interproximal (105 +/- 81 microns) margins. Ease of seating with CEREC 2 inlays was much better than with CEREC 1. CLINICAL SIGNIFICANCE: Improvements in software and hardware allow the CEREC 2 to adapt well to standard inlay cavity preparations. The ability of the device to create inlays that seat without interference is remarkable. The improved fit and ability to create the occlusal surface in a variety of ways make CEREC 2 an attractive restorative option for all-ceramic restorations.     

Chairside CAD/CAM: an overview of restorative material options

A number of categories of materials are available for chairside CAD/CAM restorations that have demonstrated predictability and longevity. These materials include esthetic and high-strength ceramics, composite resins for both final and temporary restorations, and newer nanoceramics that offer ease of handling and a glossy surface finish. Each category of materials has unique features designed for specific clinical applications. This article will examine currently available materials designed for chairside CAD/CAM restorations and the various outcomes that are possible with this technologically advanced process.