Influence of Surface Roughness on Mechanical Properties of Two Computer-aided Design/Computer-aided Manufacturing (CAD/CAM) Ceramic Materials

2012 ◽  
Vol 37 (6) ◽  
pp. 617-624 ◽  
Author(s):  
S Flury ◽  
A Peutzfeldt ◽  
A Lussi

SUMMARY The aim of this study was to evaluate the influence of surface roughness on surface hardness (Vickers; VHN), elastic modulus (EM), and flexural strength (FLS) of two computer-aided design/computer-aided manufacturing (CAD/CAM) ceramic materials. One hundred sixty-two samples of VITABLOCS Mark II (VMII) and 162 samples of IPS Empress CAD (IPS) were ground according to six standardized protocols producing decreasing surface roughnesses (n=27/group): grinding with 1) silicon carbide (SiC) paper #80, 2) SiC paper #120, 3) SiC paper #220, 4) SiC paper #320, 5) SiC paper #500, and 6) SiC paper #1000. Surface roughness (Ra/Rz) was measured with a surface roughness meter, VHN and EM with a hardness indentation device, and FLS with a three-point bending test. To test for a correlation between surface roughness (Ra/Rz) and VHN, EM, or FLS, Spearman rank correlation coefficients were calculated. The decrease in surface roughness led to an increase in VHN from (VMII/IPS; medians) 263.7/256.5 VHN to 646.8/601.5 VHN, an increase in EM from 45.4/41.0 GPa to 66.8/58.4 GPa, and an increase in FLS from 49.5/44.3 MPa to 73.0/97.2 MPa. For both ceramic materials, Spearman rank correlation coefficients showed a strong negative correlation between surface roughness (Ra/Rz) and VHN or EM and a moderate negative correlation between Ra/Rz and FLS. In conclusion, a decrease in surface roughness generally improved the mechanical properties of the CAD/CAM ceramic materials tested. However, FLS was less influenced by surface roughness than expected.

2022 ◽  
Author(s):  
eaeldwakhly not provided

This study was conducted to assess the surface characteristics in terms of roughness of two CAD/CAM (Computer-Aided-Design/Computer-Aided Manufacturing)restorative material spre and post chewing simulation exposure. Methods: Specimens were prepared from two CAD/CAM ceramic materials: Cerec Blocs C and IPS e-max ZirCAD. A total of 10 disks were prepared for each study group. 3D optical noncontact surface profiler was used to test the surface roughness (ContourGT, Bruker, Campbell, CA, USA). A silicone mold was used to fix the individual samples using a self-curing resin. Surface roughness (SR) was examined pre and post exposure to chewing simulation. 480,000 simulated chewing cycles were conducted to mimic roughly two years of intraoral clinical service. The results data was first tested for normality and equal variance (Levene’s test >0.05) then examined with paired and independent sample t-test at a significance level of (p < 0.05). Results:The two CAD-CAM materials tested exhibited increased surface roughness from baseline. The highest mean surface roughness was observed in Cerec blocs C group after chewing simulation (2.34 µm± 0.62 µm). Whereas the lowest surface roughness was observed in IPS e.max ZirCAD group before chewing simulation (0.42 µm± 0.16 µm). Both study groups exhibited significantly different surface roughness values (p< 0.05). There was a statistically higher surface roughness values after the chewing simulation in Cerec blocs C when compared to IPS e.max ZirCAD groups (p = 0.000).Conclusion:Even though both tested CAD/CAM materials differ in recorded surface roughness values, results were within clinically accepted values.


Materials ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2252 ◽  
Author(s):  
Yin ◽  
Jang ◽  
Lee ◽  
Bae

This study compares the mechanical properties and wear ability of five CAD/CAM (computer-aided design/computer-aided manufacturing) millable dental blocks. All the discs, including Amber Mill Hybrid, Vita Enamic, Katana Avencia, Lava Ultimate, and Amber Mill, were cut in dimensions of 1.2 mm in thickness and 12 mm in diameter, polished to a machined surface, and immersed in distilled water for seven days. Vickers hardness was measured and the indentations were observed using microscope. The discs were brushed under a 150 g load. Mean surface roughness (Ra) and topography were determined after 100,000 cycles. Finally the biaxial flexure strength of the discs was measured and the broken surfaces were observed using scanning electron microscopy (SEM). The data was subjected to Weibull analysis. All data were analyzed by one-way analysis (ANOVA). The results of Vickers hardness are shown as: Amber Mill > Vita Enamic > Amber Mill Hybrid > Lava Ultimate > Katana Avencia. Katana Avencia showed the highest volume percentage reduction and the roughest surface after toothbrushing. The biaxial flexural strength is shown as: Amber Mill > Katana Avencia > Lava Ultimate > Amber Mill Hybrid > Vita Enamic. All the tested materials exhibited varying degrees of mass loss and surface roughness. The properties of the composite materials are related to the filler content, filler volume, and polymerization methods.


2018 ◽  
Vol 19 (2) ◽  
pp. 196-204 ◽  
Author(s):  
Apa Juntavee ◽  
Niwut Juntavee ◽  
Phuwiwat Saensutthawijit

ABSTRACT Aim This study evaluated the effect of light-emitting diode (LED) illumination bleaching technique on the surface nanohardness of various computer-aided design and computer-aided manufacturing (CAD/CAM) ceramic materials. Materials and methods Twenty disk-shaped samples (width, length, and thickness = 10, 15, and 2 mm) were prepared from each of the ceramic materials for CAD/CAM, including Lava™ Ultimate (LV), Vita Enamic® (En) IPS e.max® CAD (Me), inCoris® TZI (IC), and Prettau® zirconia (Pr). The samples from each type of ceramic were randomly divided into two groups based on the different bleaching techniques to be used on them, using 35% hydrogen peroxide with and without LED illumination. The ceramic disk samples were bleached according to the manufacturer's instruction. Surface hardness test was performed before and after bleaching using nanohardness tester with a Berkovich diamond indenter. Results The respective Vickers hardness number upon no bleaching and bleaching without or with LED illumination [mean ± standard deviation (SD)] for each type of ceramic were as follows: 102.52 ± 2.09, 101.04 ± 1.18, and 98.17 ± 1.15 for LV groups; 274.96 ± 5.41, 271.29 ± 5.94, and 268.20 ± 7.02 for En groups; 640.74 ± 31.02, 631.70 ± 22.38, and 582.32 ± 33.88 for Me groups; 1,442.09 ± 35.07, 1,431.32 ± 28.80, and 1,336.51 ± 34.03 for IC groups; and 1,383.82 ± 33.87, 1,343.51 ± 38.75, and 1,295.96 ± 31.29 for Pr groups. The results indicated surface hardness reduction following the bleaching procedure of varying degrees for different ceramic materials. Analysis of variance (ANOVA) revealed a significant reduction in surface hardness due to the effect of bleaching technique, ceramic material, and the interaction between bleaching technique and ceramic material (p < 0.05). Conclusion Bleaching resulted in a diminution of the surface hardness of dental ceramic for CAD/CAM. Using 35% hydrogen peroxide bleaching agent with LED illumination exhibited more reduction in surface hardness of dental ceramic than what was observed without LED illumination. Clinical significance Clinicians should consider protection of the existing restoration while bleaching. How to cite this article Juntavee N, Juntavee A, Saensutthawijit P. Influences of Light-emitting Diode Illumination Bleaching Technique on Nanohardness of Computer-aided Design and Computer-aided Manufacturing Ceramic Restorative Materials. J Contemp Dent Pract 2018;19(2):196-204.


2019 ◽  
Vol 44 (1) ◽  
pp. 88-95 ◽  
Author(s):  
G Daryakenari ◽  
H Alaghehmand ◽  
A Bijani

SUMMARY Objective: Computer aided design-computer aided machining (CAD-CAM) ceramic crowns are replacing ceramo-metal ones due to newly developed mechanical properties and esthetics. To obtain knowledge about their interactions due to polishing and occlusal contacts with the opposing dental enamel specimen, including surface roughness and wear, the three-body wear simulation was investigated. Methods and Materials: The surface roughness (RA) and wear rate (mm) of four CAD-CAM blocks with different compositions including Vita Mark II, e.max, Suprinity, and Enamic, after two surface treatments of glazing and polishing, and their opposing enamel specimens, were investigated using a mastication simulator and atomic force microscope. Results: The roughness of all ceramic and to a greater extent enamel samples, with the exception of enamel opposing polished Enamic samples, was decreased after wear. No significant difference in wear was evident for the ceramic samples between the glazed and polished treatments. Lower wear rates were recorded only for polished Vita Mark II and polished Enamic in comparison to the glazed ones. Conclusion: The newly developed polishing systems for CAD-CAM ceramics can be good alternatives to reglazing, because the roughness and wear rate of both the ceramic and the opposing enamel will either not change or decrease.


2019 ◽  
Vol 45 (4) ◽  
pp. 407-415 ◽  
Author(s):  
P Nassary Zadeh ◽  
N Lümkemann ◽  
M Eichberger ◽  
B Stawarczyk ◽  
M Kollmuss

Clinical Relevance As temporary materials are often used in prosthetic dentistry, there is need to investigate their behavior in the oral environment. Parameters such as surface roughness and surface free energy correlate to the level of plaque adhesion, which can impact gingival health. SUMMARY Objective: To test computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated and conventionally processed polymer-based temporary materials in terms of radiopacity (RO), surface free energy (SFE), surface roughness (SR), and plaque accumulation (PA). Methods and Materials: Six temporary materials (n=10/n=10) were tested, including three CAD/CAM-fabricated (CC) materials—Art Bloc Temp (CC-ABT), Telio CAD (CC-TC), and VITA CAD Temp (CC-VCT)—and three conventionally processed (cp) materials: Integrity Multi Cure (cp-IMC), Luxatemp Automix Plus (cp-LAP), and Protemp 4 (cp-PT4). Zirconia acted as the control group (CG, n=10). RO was evaluated according to DIN EN ISO 13116. SFE was investigated using contact angle measurements. SR was measured using a profilometer. The PA tests were performed using three microorganisms: Streptococcus mutans, Actinomyces naeslundii, and Veillonella parvula. Data were analyzed using Kolmogorov-Smirnov, Kruskal-Wallis, Mann-Whitney U-, Dunn-Bonferroni, Wilcoxon, Levene, and Pearson tests and one-way analysis of variance with post hoc Scheffé test (α=0.05). Results: No radiopacity was observed for any CC material or cp-PT4. CG showed the highest RO, while no differences between cp-IMC and cp-LAP were found. CG showed lower SFE compared to all polymer temporary materials, except in the case of CC-TC. cp-LAP and cp-IMC presented higher SFE than did CC-TC and CG. CC-ABT presented lower initial SR values compared to cp-PT4 and cp-LAP. For cp-LAP, a higher initial SR was measured than for all CAD/CAM materials and cp-IMC. All specimens showed a certain amount of PA after the incubation period. A naeslundii and V parvula resulted in comparable PA values, whereas the values for S mutans were lower by one log level. CAD/CAM materials showed superior results for SR, SFE, and PA, whereas all materials lacked RO.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Kristýna Hynková ◽  
Iva Voborná ◽  
Bernard Linke ◽  
Liran Levin

Abstract Nowadays, patients require the highest quality of treatment, but generally prefer to spend as little time as possible in the dental chair. Therefore, there is significant benefit for using new technologies such as CAD/CAM (computer aided design/computer aided manufacturing), which provides both quality and speed. There is an increase in ceramic materials and ceramic blocks/discs available, with varying properties. This has resulted in some confusion and difficulty in making an informed decision about which material is best for a specific clinical situation. The objective of this review is to provide an overview and comparison of basic mechanical properties of currently used CAD/CAM ceramic materials based on a review of the currently available literature.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Jaafar Abduo ◽  
Karl Lyons

Despite the predictable longevity of implant prosthesis, there is an ongoing interest to continue to improve implant prosthodontic treatment and outcomes. One of the developments is the application of computer-aided design and computer-aided manufacturing (CAD/CAM) to produce implant abutments and frameworks from metal or ceramic materials. The aim of this narrative review is to critically evaluate the rationale of CAD/CAM utilization for implant prosthodontics. To date, CAD/CAM allows simplified production of precise and durable implant components. The precision of fit has been proven in several laboratory experiments and has been attributed to the design of implants. Milling also facilitates component fabrication from durable and aesthetic materials. With further development, it is expected that the CAD/CAM protocol will be further simplified. Although compelling clinical evidence supporting the superiority of CAD/CAM implant restorations is still lacking, it is envisioned that CAD/CAM may become the main stream for implant component fabrication.


Author(s):  
A. N. Bozhko

Computer-aided design of assembly processes (Computer aided assembly planning, CAAP) of complex products is an important and urgent problem of state-of-the-art information technologies. Intensive research on CAAP has been underway since the 1980s. Meanwhile, specialized design systems were created to provide synthesis of assembly plans and product decompositions into assembly units. Such systems as ASPE, RAPID, XAP / 1, FLAPS, Archimedes, PRELEIDES, HAP, etc. can be given, as an example. These experimental developments did not get widespread use in industry, since they are based on the models of products with limited adequacy and require an expert’s active involvement in preparing initial information. The design tools for the state-of-the-art full-featured CAD/CAM systems (Siemens NX, Dassault CATIA and PTC Creo Elements / Pro), which are designed to provide CAAP, mainly take into account the geometric constraints that the design imposes on design solutions. These systems often synthesize technologically incorrect assembly sequences in which known technological heuristics are violated, for example orderliness in accuracy, consistency with the system of dimension chains, etc.An AssemBL software application package has been developed for a structured analysis of products and a synthesis of assembly plans and decompositions. The AssemBL uses a hyper-graph model of a product that correctly describes coherent and sequential assembly operations and processes. In terms of the hyper-graph model, an assembly operation is described as shrinkage of edge, an assembly plan is a sequence of shrinkages that converts a hyper-graph into the point, and a decomposition of product into assembly units is a hyper-graph partition into sub-graphs.The AssemBL solves the problem of minimizing the number of direct checks for geometric solvability when assembling complex products. This task is posed as a plus-sum two-person game of bicoloured brushing of an ordered set. In the paradigm of this model, the brushing operation is to check a certain structured fragment for solvability by collision detection methods. A rational brushing strategy minimizes the number of such checks.The package is integrated into the Siemens NX 10.0 computer-aided design system. This solution allowed us to combine specialized AssemBL tools with a developed toolkit of one of the most powerful and popular integrated CAD/CAM /CAE systems.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou

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.


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