Computer-Aided Designed/Computer-Assisted Manufactured (CAD/CAM) All-Ceramic Crowns Appear to Perform Better than All-Composite Resin Crowns Following the First 3 Years of Placement

2011 ◽  
Vol 11 (4) ◽  
pp. 203-205 ◽  
Author(s):  
J. Robert Kelly
Keyword(s):  
Composite Resin ◽  
Computer Assisted ◽  
All Ceramic ◽  
Computer Aided ◽  
Cad Cam ◽  
Ceramic Crowns ◽  
Better Than

Premolar Axial Wall Height Effect on CAD/CAM Crown Retention

2016 ◽  
Vol 41 (6) ◽  
pp. 666-671 ◽  
Author(s):  
C Gillette ◽  
R Buck ◽  
N DuVall ◽  
S Cushen ◽  
M Wajdowicz ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Lithium Disilicate ◽  
Resin Cement ◽  
Failure Resistance ◽  
All Ceramic ◽  
Computer Aided ◽  
Cad Cam ◽  
Ceramic Crowns ◽  
Aided Design ◽  
Post Hoc

SUMMARY Objective: To evaluate the significance of reduced axial wall height on retention of adhesively luted, all-ceramic, lithium disilicate premolar computer-aided design/computer-aided manufacturing (CAD/CAM) crowns based on preparations with a near ideal total occlusal convergence of 10°. Methods: Forty-eight recently extracted premolars were randomly divided into four groups (n=12). Each group received all-ceramic CAD/CAM crown preparations featuring axial wall heights of 0, 1, 2, and 3 mm, respectively, all with a 10° total occlusal convergence. Scanned preparations were fitted with lithium disilicate all-ceramic crowns that were luted with a self-etching resin cement. Specimens were tested to failure at a 45° angle to the tooth long axis with failure load converted to megapascals (MPa) based on the measured bonding surface area. Mean data were analyzed using analysis of variance/Tukey's post hoc test (α=0.05). Results: Lithium disilicate crowns adhesively luted on preparations with 0 axial wall height demonstrated significantly less failure resistance compared with the crowns luted on preparations with axial wall heights of 1 to 3 mm. There was no failure stress difference between preparations with 1 to 3 mm axial wall height. Conclusions: Under conditions of this study, adhesively luted lithium disilicate bicuspid crowns with a total occlusal convergence of 10° demonstrated similar failure resistance independent of axial wall height of 1 to 3 mm. This study provides some evidence that adhesion combined with an ideal total occlusal convergence may compensate for reduced axial wall height.

Accuracy of Ceramic Restorations Made Using an In-office Optical Scanning Technique: An In Vitro Study

2014 ◽  
Vol 39 (3) ◽  
pp. 308-316 ◽  
Author(s):  
P Tidehag ◽  
K Ottosson ◽  
G Sjögren
Keyword(s):  
Glass Ceramic ◽  
In Vitro Study ◽  
Vitro Study ◽  
Digital Impression ◽  
All Ceramic ◽  
Computer Aided ◽  
Cad Cam ◽  
Ceramic Crowns ◽  
Ceramic Crown

SUMMARY The present in vitro study concerns determination of the pre-cementation gap width of all-ceramic crowns made using an in-office digital-impression technique and subsequent computer-aided design/computer-aided manufacturing (CAD/CAM) production. Two chairside video camera systems were used: the Lava Oral scanner and Cadent's iTero scanner. Digital scans were made of a first molar typodont tooth that was suitably prepared for an all-ceramic crown. The digital impressions were sent via the Internet to commercial dental laboratories, where the crowns were made. Also, an impression of the typodont tooth was made, poured, and scanned in order to evaluate the pre-cementation gap of crowns produced from scanning stone dies. These methods and systems were evaluated by creating replicas of the intermediate space using an addition-cured silicone, and the gap widths were determined using a measuring microscope. Hot-pressed leucite-reinforced glass-ceramic crowns were selected as a reference. The mean value for the marginal measuring points of the control was 170 μm, and the values for all the evaluated crowns ranged from 107 to 128 μm. Corresponding figures for the internal measuring points were 141-210 μm and 115-237 μm, respectively. Based on the findings in the present study, an in-office digital-impression technique can be used to fabricate CAD/CAM ceramic single crowns with a marginal and internal accuracy that is on the same level as that of a conventional hot-pressed glass-ceramic crown. In the present study, however, slight differences could be seen between the two types of ceramic crowns studied with respect to the internal fit obtained.

Influence of Computer-aided Design/Computer-aided Manufacturing Diamond Bur Wear on Marginal Misfit of Two Lithium Disilicate Ceramic Systems

2019 ◽  
Vol 45 (4) ◽  
pp. 416-425
Author(s):  
LH Raposo ◽  
PS Borella ◽  
DC Ferraz ◽  
LM Pereira ◽  
MS Prudente ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Composite Resin ◽  
Lithium Disilicate ◽  
Computer Aided Manufacturing ◽  
Diamond Bur ◽  
Significant Difference ◽  
Computer Aided ◽  
Cad Cam ◽  
Ceramic Crowns ◽  
Aided Design

Clinical Relevance Marginal misfit of monolithic lithium disilicate ceramic crowns obtained from a chairside computer-aided design/computer-aided manufacturing system is affected after successive millings using a single diamond bur set. This fact can be critical for the longevity of indirect restorations. SUMMARY Objectives: This laboratory study aimed to assess the effect of successive crown millings on the marginal misfit of monolithic full-ceramic restorations obtained from two lithium disilicate systems, with a single diamond bur set used for each material in a chairside computer-aided design/computer-aided manufacturing (CAD/CAM) unit. Methods and Materials: Initially, 36 standardized composite resin dies were produced by additive manufacturing from a three-dimensional model of a right mandibular first molar with full-crown preparation generated in CAD software. Individual ceramic crowns were obtained in a chairside CAD/CAM unit (CEREC MC XL) for each composite resin die according to the ceramic system (IPS e.max CAD and Rosetta SM; n=18). Two new diamond burs were used as a set for obtaining the crowns in each experimental group (ceramic systems), and the milling periods were defined after three crown millings (T0-T6), when the diamond bur set of each system was removed for morphologic characterization using scanning electron microscopy (SEM). The marginal misfit of the crowns was assessed through coronal and sagittal micro-tomographic sectioning, in the vertical and horizontal directions of the ceramic crowns seated on their respective resin dies. The collected data were tabulated and subjected to one-way analysis of variance and Tukey's honestly significant difference test (α=0.05). Results: SEM images showed changes in the superficial morphology of the diamond bur sets, with progressive loss of the diamond granules after the successive millings of crowns for both experimental groups. Significant differences were detected in the marginal misfit of the crowns from both ceramic systems at the different milling periods (p<0.001). Conclusions: Diamond burs deteriorated after successive crown millings for both lithium disilicate ceramic systems. The marginal misfit of the crowns obtained increased with the successive use of the CAD/CAM diamond bur set employed for milling each ceramic material. In addition, new milling of full lithium disilicate ceramic crowns can be inappropriate after 11 successive millings for IPS e.max CAD and 12 for Rosetta SM, due to the increased marginal misfit observed under the parameters tested.

CAD/CAM Polymer vs Direct Composite Resin Core Buildups for Endodontically Treated Molars Without Ferrule

2016 ◽  
Vol 41 (1) ◽  
pp. 53-63 ◽  
Author(s):  
J-F Güth ◽  
D Edelhoff ◽  
J Goldberg ◽  
P Magne
Keyword(s):  
Glass Ceramic ◽  
High Performance ◽  
Composite Resin ◽  
Fracture Load ◽  
High Performance Polymer ◽  
Resin Core ◽  
All Ceramic ◽  
Cad Cam ◽  
Light Curing ◽  
Ceramic Crowns

SUMMARY Objectives The aim of this study was to investigate the restoration of broken-down endodontically treated molars without ferrule effect using glass ceramic crowns on different composite resin core buildups. Methods and Materials Forty-five decoronated endodontically treated teeth (no ferrule) were restored with a semidirect buildup using an experimental computer-aided design/computer-aided manufacturing (CAD/CAM) high-performance polymer (HPP group) or with light-curing composite core buildups of Tetric EvoCeram with (TECP group) or without (TEC group) a glass-fiber-reinforced post. All teeth were prepared to receive bonded glass ceramic crowns (Empress CAD luted with Variolink II) and were subjected to accelerated fatigue testing. Cyclic isometric loading was applied to the palatal cusp at an angle of 30° and a frequency of 5 Hz, beginning with a load of 200 N (×5000 cycles) and followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles. Groups were compared using the life-table survival analysis (log rank test at p=0.05). Average fracture loads and number of survived cycles were compared with one-way analysis of variance (Scheffé post hoc at p=0.05). Results None of the tested specimen withstood all 185,000 load cycles. There was a significant difference in mean fracture load, survived cycles, and survival; the HPP group (fracture load 975.27N±182.74) was significantly higher than the TEC (716.87N±133.43; p=0.001) and TECP (745.67±156.34; p=0.001) groups, and the TEC and TECP groups showed no difference (p=0.884). Specimens in the TECP group were affected by an initial failure phenomenon (wide gap at the margin between the buildup/crown assembly and the root). Conclusions Semidirect core buildup made from high-performance polymer enhanced the performance of all-ceramic leucite-reinforced glass ceramic crowns compared with direct light-curing composite resin buildups. The use of a fiber-reinforced post system did not influence the fatigue strength of all-ceramic crowns.

scholarly journals Dual-scan technique for the customization of zirconia computer-aided design/computer-aided manufacturing frameworks

2013 ◽  
Vol 07 (S 01) ◽  
pp. S115-S118 ◽  
Author(s):  
Rafael Ferrone Andreiuolo ◽  
Carlos Eduardo Sabrosa ◽  
Katia Regina H. Cervantes Dias
Keyword(s):  
Computer Aided Design ◽  
Uniform Thickness ◽  
Simple Manner ◽  
Computer Aided Manufacturing ◽  
All Ceramic ◽  
Computer Aided ◽  
Cad Cam ◽  
Ceramic Crowns ◽  
Tooth Preparation ◽  
Aided Design

ABSTRACTThe use of bi-layered all-ceramic crowns has continuously grown since the introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia cores. Unfortunately, despite the outstanding mechanical properties of zirconia, problems related to porcelain cracking or chipping remain. One of the reasons for this is that ceramic copings are usually milled to uniform thicknesses of 0.3-0.6 mm around the whole tooth preparation. This may not provide uniform thickness or appropriate support for the veneering porcelain. To prevent these problems, the dual-scan technique demonstrates an alternative that allows the restorative team to customize zirconia CAD/CAM frameworks with adequate porcelain thickness and support in a simple manner.

Computer-aided evaluation of preparations for CAD/CAM-fabricated all-ceramic crowns

2012 ◽  
Vol 17 (5) ◽  
pp. 1389-1395 ◽  
Author(s):  
Jan-Frederik Güth ◽  
Jan Wallbach ◽  
Michael Stimmelmayr ◽  
Wolfgang Gernet ◽  
Florian Beuer ◽  
...  
Keyword(s):  
All Ceramic ◽  
Computer Aided ◽  
Cad Cam ◽  
Ceramic Crowns

scholarly journals Evaluation of the Feasibility of NaCaPO4-Blended Zirconia as a New CAD/CAM Material for Dental Restoration

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou
Keyword(s):  
Computer Aided Design ◽  
Optical Microscope ◽  
Dental Restoration ◽  
Numerical Control ◽  
Test Results ◽  
Cnc Machine ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design ◽  
Better Than

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO4-blended zirconia as a new CAD/CAM material. Eleven different proportional samples of zirconia and NaCaPO4 (xZyN) were prepared and characterized by X-ray diffractometry (XRD) and Vickers microhardness, and the milling property of these new samples was tested via a digital optical microscope. After calcination at 950 °C for 4 h, XRD results showed that the intensity of tetragonal ZrO2 gradually decreased with an increase in the content of NaCaPO4. Furthermore, with the increase in NaCaPO4 content, the sintering became more obvious, which improved the densification of the sintered body and reduced its porosity. Specimens went through milling by a computer numerical control (CNC) machine, and the marginal integrity revealed that being sintered at 1350 °C was better than being sintered at 950 °C. Moreover, 7Z3N showed better marginal fit than that of 6Z4N among thirty-six samples when sintered at 1350 °C (p < 0.05). The milling test results revealed that 7Z3N could be a new CAD/CAM material for dental restoration use in the future.

scholarly journals Chairside CAD/CAM Materials: Current Trends of Clinical Uses

Biology ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1170
Author(s):  
Giulio Marchesi ◽  
Alvise Camurri Piloni ◽  
Vanessa Nicolin ◽  
Gianluca Turco ◽  
Roberto Di Lenarda
Keyword(s):  
Clinical Outcome ◽  
Computer Aided Design ◽  
Fabrication Process ◽  
Computer Assisted ◽  
Current Trends ◽  
Computer Aided ◽  
Restorative Materials ◽  
Cad Cam ◽  
Aided Design

Restorative materials are experiencing an extensive upgrade thanks to the use of chairside Computer-aided design/computer-assisted manufacturing (CAD/CAM) restorations. Therefore, due to the variety offered in the market, choosing the best material could be puzzling for the practitioner. The clinical outcome of the restoration is influenced mainly by the material and its handling than by the fabrication process (i.e., CAD/CAM). Information on the restorative materials performances can be difficult to gather and compare. The aim of this article is to provide an overview of chairside CAD/CAM materials, their classification, and clinically relevant aspects that enable the reader to select the most appropriate material for predictable success.

scholarly journals The Tooth as a Basis for Biomimetic Design

2000 ◽  
Author(s):  
Van P. Thompson ◽  
Stephen Kao ◽  
Ivory Kirkpatrick
Keyword(s):  
High Cycle Fatigue ◽  
Critical Role ◽  
Contact Loads ◽  
All Ceramic ◽  
Cad Cam ◽  
Molar Teeth ◽  
Natural Teeth ◽  
Wide Transition ◽  
Ceramic Crowns ◽  
Improved Performance

Abstract Teeth are uniquely capable of withstanding high forces (&gt;200 N) with small contact area (&lt; 0.5 mm2) and a high number of fatigue cycles (&gt; 107) with little evidence of damage. Yet the tooth is comprised of an outer very brittle, anisotropic, highly crystalline enamel layer supported by an inner soft, but tough dentin. These structures are joined by a small (appoximately 30 microns wide) transition zone called the dento-enamel junction (DEJ). The DEJ plays a critical role in transfer of stress across the layers of the tooth. How the enamel-dentin complex (EDC) comprised of these layers and the DEJ is able to withstand the high contact loads and high cycle fatigue is not well understood. An understanding of the interplay of the various components would serve as the basis for design of dental ceramic or resin based composite crowns capable of service lives approaching those on natural teeth. Current all ceramic crowns have high failure rates (1–5% per yr) on molar teeth and improved performance is required before CAD-CAM restorations can be successful.

Sign in / Sign up

Export Citation Format

Share Document