Evaluation of Wear Resistance of Dental Chairside CAD/CAM Glass Ceramics Reinforced by Different Crystalline Phases

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Qianqian Zhang ◽  
Shanshan Gao ◽  
Chunxu Liu ◽  
Yuqing Lu ◽  
Xin Chen ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Computer Aided Design ◽  
Artificial Saliva ◽  
Three Dimensional ◽  
Glass Ceramics ◽  
Lithium Disilicate ◽  
Load Force ◽  
Wear Depth ◽  
Computer Aided ◽  
Cad Cam

The mechanical properties of crystalline phase of glass ceramics are critical. This study aimed to evaluate wear resistance of different crystalline-reinforced dental chairside computer-aided design/computer-aided manufacturing (CAD/CAM) glass ceramics. Materials of feldspar (Vita Mark II, VM), leucite (IPS Empress CAD, EC), lithium disilicate (IPS e.max CAD, EX), lithium disilicate enriched with zirconia (Vita Suprinity, VS), and enamel were embedded, grounded, and polished, respectively. Samples were indented with a Vickers hardness tester to test the fracture resistance (KIC). Two-body wear tests were performed in a reciprocal ball-on-flat configuration under artificial saliva. The parameters of load force (50 N), reciprocating amplitude (500 μm), frequency (2 Hz), and the test cycle (10,000 cycles) were selected. Specimen microstructure, indentation morphology, and wear scars were observed by scanning electron microscope (SEM), optical microscopy, and three-dimensional profile microscopy. EX, VS, and EC demonstrated significantly higher KIC values than the enamel, while ceramic materials showed smaller wear depth results. Cracks, massive delamination, and shallow plow were seen on the enamel worn scar. Long deep plow, delamination, and brittle cracks are more common for VM and EC, and short shallow plow and smooth subsurface are the characteristics of EX and VS. Greater fracture toughness values indicated higher wear resistances of the materials for the test glass ceramics. The CAD/CAM glass ceramics performed greater wear resistance than enamel. Feldspar- and leucite-reinforced glass ceramics illustrated better wear resistance similar to enamel than lithium disilicate glass ceramics, providing amicable matching with the opposite teeth.

TRI BOLOGICAL STUDIES OF LAYERED BIOMATERIALS FOR PROSTHETIC STRUCTURES BASED ON SUBSTRUCTURES MADE OF DIGITAL TECHNOLOGIES

Tribologia ◽  
2019 ◽  
Vol 287 (5) ◽  
pp. 87-99
Author(s):  
Wojciech RYNIEWICZ ◽  
Łukasz BOJKO ◽  
Anna M. RYNIEWICZ ◽  
Małgorzata PIHUT ◽  
Paweł PAŁKA
Keyword(s):  
Wear Resistance ◽  
Friction Coefficient ◽  
Computer Aided Design ◽  
Artificial Saliva ◽  
Scanning Microscope ◽  
Technological Parameters ◽  
Stomatognathic System ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design

Modern dental prosthetics uses CAD/CAM in the Computer Aided Design (CAD) of substructures and its Computer Aided Manufacturing (CAM) process. The substructure is subject to appropriate veneering, which determines the functional cooperation. The aim of this study is to investigate the friction coefficient and wear resistance of the veneering layers of the substructures of prosthetic structures. The test materials are dedicated veneering layers on substructures made of factory-made CoCr, TiCP, and Ti6Al4V metal fittings as well as the glass-ceramic material LiSi2 and the ceramic ZrO2. The study was conducted on a Roxana Machine Works tribological machine in the ball-and-3discs system in an artificial saliva environment using a Hitachi S3400 scanning microscope. As a reference biomaterial, enamel-dentin discs were used. The tribological processes that take place under chewing conditions in the presence of saliva depend on the properties and technological parameters of the surface layer of the biomaterial wearing out and on the enamel of opposing teeth in contact, which also wears out. They should reproduce the physiological nature of adjustment wear in the stomatognathic system (SS). The determined values of the friction coefficient and wear resistance allowed differences to be indicated in the course of tribological processes, and microscopic analyses confirmed them.

scholarly journals The Effects of a coffee beverage and whitening systems on surface roughness and gloss of CAD/CAM lithium disilicate glass ceramics

2021 ◽  
Vol 19 ◽  
pp. 228080002110588
Author(s):  
Sarah S. Al-Angari ◽  
Shahad Meaigel ◽  
Nouf Almayouf ◽  
Shahad Quwayhis ◽  
Abdulelah Aldahash ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Computer Aided Design ◽  
Glass Ceramics ◽  
Lithium Disilicate ◽  
Control Group ◽  
Computer Aided ◽  
Cad Cam ◽  
The Mean ◽  
Surface Gloss ◽  
Cam Systems

Objectives: To investigate the effects of a coffee beverage and two whitening systems on the surface roughness and gloss of glazed Lithium Disilicate Glass-Ceramics (LDGC) for computer-aided design/computer-aided manufacturing (CAD/CAM) systems. Methods: Sixty-eight LDGC disks (12 × 10 × 2 mm) were prepared from blocks of CAD/CAM systems (IPS e.max CAD ceramic). Baseline measurements for surface roughness (Ra) and gloss (GU) were taken using a 3-D optical profilometer and a glossmeter, respectively; then specimens were randomized into four groups ( n = 17). All specimens were immersed in a coffee solution (24 h × 12 days) then subjected to two whitening systems. G1-negative control (kept moist × 7 days); G2-positive control (brushed with distilled water, 200 g/load, 2 min twice daily × 7 days); G3-whitening toothpaste (Colgate optic white; relative dentin abrasivity (RDA) = 100, 200 g/load, 2 min twice daily × 7 days); and G4-simulated at-home bleaching protocol (Opalescence,15% carbamide peroxide (CP), 6 h/day × 7 days). The study outcomes were measured at baseline and after the treatments. Data were analyzed using paired T-test and one-way ANOVA (α = 0.05). Results: The mean surface roughness significantly increased ( p ⩽ 0.002) for all groups after the designated treatment protocols. Among groups, the mean surface roughness of G2 and G3 were significantly higher ( p ⩽ 0.001) (Ra: 0.51 and 0.57 μm, respectively) compared to the control group (Ra: 0.23 μm), and were not significantly different from G4 (Ra: 0.46 μm). Surface gloss decreased with no significant change within or among groups after treatment. Conclusion: All glazed LDGC had a significant increase in surface roughness after being subjected to simulated 1 year of coffee drinking and whitening systems (15% CP and whitening toothpaste), and the greatest change was associated with brushing (simulating 8 months). However, coffee beverages and whitening systems had no significant effect on the surface gloss.

scholarly journals Monitoring Alveolar Ridge Remodelling Post-Extraction Using Sequential Intraoral Scanning over a Period of Four Months

2020 ◽  
Vol 17 (18) ◽  
pp. 6638
Author(s):  
Khaled E. Ahmed
Keyword(s):  
Computer Aided Design ◽  
Three Dimensional ◽  
Dimensional Changes ◽  
Intraoral Scanning ◽  
Computer Aided ◽  
Potential Applications ◽  
Cad Cam ◽  
Aided Design ◽  
2D And 3D

The potential applications of computer-aided design/computer-aided manufacturing (CAD/CAM) and intraoral scanning exceed the delivery of standard prosthodontic interventions. The aim of this study was to clinically present a developed assessment technique, that relies on the use of sequential intraoral scanning, three-dimensional superimposition, and 2D and 3D deviation analyses based on a standardised protocol, as an auxiliary tool in monitoring dimensional changes of residual ridge post-extraction with a follow-up period of four months.

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.

Monolithic Lithium Disilicate Full-Contour Crowns Bonded on CAD/CAM Zirconia Complete-Arch Implant Bridges With 3 to 5 Years of Follow-Up

2015 ◽  
Vol 41 (4) ◽  
pp. 450-458 ◽  
Author(s):  
Alessandro Pozzi ◽  
Marco Tallarico ◽  
Alberto Barlattani
Keyword(s):  
Soft Tissue ◽  
Computer Aided Design ◽  
Lithium Disilicate ◽  
Additional Treatment ◽  
Success Rates ◽  
Association Index ◽  
Randomized Controlled Studies ◽  
Computer Aided ◽  
Cad Cam

This study was carried on to assess the clinical performance of a novel restorative concept consisting in single monolithic lithium disilicate full-contour crowns bonded on computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia complete-arch implant bridges, to overcome the drawbacks related to the chipping of porcelain fused to zirconia restorations. Sixteen patients received 18 implant-supported hybrid screw-cement-retained complete-arch restorations, consisting of single monolithic lithium disilicate full-contour crowns bonded on CAD/CAM zirconia frameworks. The restorations were supported by 4–8 implants. All patients were followed up for at least 3 years on function (range 36 to 60 months, mean 49.3 months). Clinical controls were scheduled every 4 months. The outcomes were implant and prosthetic survival and success rates, any complications, patient satisfaction, and soft tissue parameters. No dropouts occurred. The overall implant and prosthesis survival rates were 100%. One of 18 restorations (1 of 236 dental units) showed a chip-off fracture of the veneering ceramic that was polished intraorally without any additional treatment, scoring a cumulative prosthetic success rate of 100%, according to the California Dental Association index. All patients were functionally and esthetically highly satisfied with their restorations. Successful soft tissue parameters were found around all implants. Single monolithic lithium disilicate full-contour crowns, bonded on CAD/CAM screw-retained complete-arch zirconia frameworks, showed favorable preliminary outcomes with medium-term follow-up. However, randomized controlled studies of this technique are required for further conclusive recommendations.

scholarly journals VIRTUAL TECHNOLOGIES IN DENTISTRY

2020 ◽  
pp. 606-612
Author(s):  
S.V. KAZUMYAN ◽  
◽  
I.A. DEGTEV ◽  
V.V. BORISOV ◽  
K.A. ERSHOV
Keyword(s):  
Computer Aided Design ◽  
Three Dimensional ◽  
Interdisciplinary Treatment ◽  
Digital Dentistry ◽  
Dental Restorations ◽  
Technological Advances ◽  
Planning Approach ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design

The article represents the information that in the age of digital dentistry, virtual treatment planning is becoming an increasingly important element of dental practice. With new technological advances in computer-aided design and computer-aided manufacturing (CAD/CAM) of dental restorations, predictable interdisciplinary treatment using a reverse planning approach appears to be beneficial and feasible. It is noted that thanks to achievements in medical imaging and computer programming, 2D axial images can be processed into other reformatted representations (sagittal and coronal) and three-dimensional (3D) virtual models representing the patient’s anatomy. It is shown that telemedicine occupies a special place among modern technologies in dentistry, which is used both for remote consultation and for the successful treatment of patients. Keywords: Virtual assistants , virtual nurses, voice technologies, artificial intelligence, virtual reality, 3D printing, telemedicine.

Comparison of Marginal Adaptation of Different Resin-Ceramic CAD/CAM Crowns: An In Vitro Study

2020 ◽  
pp. 232020682097597
Author(s):  
Ece Irem Oguz ◽  
Mehmet Ali Kılıçarslan ◽  
Merve Erdog˘ Özgür ◽  
Kaan Orhan ◽  
Sohaib Shujaat
Keyword(s):  
Analysis Of Variance ◽  
Computer Aided Design ◽  
Three Dimensional ◽  
In Vitro Study ◽  
Vitro Study ◽  
Marginal Adaptation ◽  
Computer Aided ◽  
Cad Cam ◽  
Marginal Discrepancy

Aim: To compare the marginal adaptation of crowns fabricated by using three different resin-ceramic computer-aided design/computer-aided manufacturing (CAD/CAM) materials. Materials and Methods: Crowns fabricated from three different resin-ceramic CAD/CAM blocks, applied on a typodont premolar (#14), were tested with regard to marginal adaptation, in this in vitro study. The typodont maxillary first premolar was prepared to serve as the master die and digitized with an intraoral scanner. The same virtual crown design was used to fabricate all specimens. Forty-eight crowns were fabricated from the same virtual crown design using three different CAD/CAM resin-ceramic blocks as follows ( n = 16): Lava Ultimate (LU), GC Cerasmart (GC), Vita Enamic (VE). Master die and crowns were scanned with a laboratory scanner and three-dimensional data were transferred into three-matic software. The software calculated the mean of the marginal discrepancy (MD) for each crown in negative and positive values, representing under and over estimation of the crown margin, respectively. A marginal discrepancy index (MDI) was obtained for each group using negative and positive MDs. All data were statistically analyzed using one-way analysis of variance and Tukey’s honest significance test ( α = 0.05). Results: The analysis of variance showed no statistical differences between materials regarding the negative and positive MDs ( P > .05). The MDI for LU was lower than GC and VE ( P < .05). Conclusion: The marginal adaptation of different resin-ceramic materials was different with regard to MDI values. Nevertheless, the MD values of all groups were within the clinically acceptable range.

scholarly journals Computer aided design and manufacturing of dental restorations - “computerized impression” technology

2006 ◽  
Vol 53 (1) ◽  
pp. 42-53 ◽  
Author(s):  
Aleksandar Todorovic ◽  
Vojkan Lazic
Keyword(s):  
Computer Aided Design ◽  
Dental Treatment ◽  
Three Dimensional ◽  
3D Measurement ◽  
Dental Restorations ◽  
Computer Aided ◽  
Cad Cam ◽  
Three Dimensional Models ◽  
Aided Design ◽  
Cam Systems

CAD/CAM technology (Computer Aided Design / Computer Aided Manufacturing) in the matter of fact helps in design and development of two-dimensional or three-dimensional models and their realization on numerical controlled machines. The key to direct or indirect CAD/CAM dental restorations is the measurement of dental preparation in the mouth or on the plaster die. The aim of this paper is to describe the possibilities and the way of function of different computer aided inspection (CAI) systems as a first part of CAD/CAM systems. Different researchers have presented several approaches of methods for three dimensional (3D) measurement. Today, for chairside dental treatment, only the optical method of measurement has lead to satisfactory results in practice. Laboratory CAD/CAM systems use mechanical and optical technologies for 3D measurement. Optical impression grows as a leader of CAI segment of almost every new CAD/CAM system. The most important properties of 3D scanners are: accuracy, volume and speed of measurement and ergonomy of instrument. .

scholarly journals Efeito da fumaça de cigarro e escovação simulada na cêramica vítrea de dissilicato de lítio CAD/CAM

2021 ◽  
Vol 13 (4) ◽  
pp. e7296
Author(s):  
Magna Andréa Rabêlo Diógenes ◽  
Francisca Tauliane Lemos de Castro ◽  
Samara Kelly da Silva Cavalcante ◽  
Ana Carolina Matias Dinelly Pinto ◽  
Pedro Henrique Chaves Isaias ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Lithium Disilicate ◽  
Computer Aided Manufacturing ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design

Objetivo: Revisar acerca do efeito da fumaça do cigarro, associada ou não à escovação, na rugosidade superficial e na microdureza de uma cerâmica vítrea de dissilicato de lítio “Computer-Aided Design/Computer-Aided Manufacturing” (CAD/CAM). Métodos: Pesquisaram-se os descritores cadastrados no MeSH “lithium disilicate”, “smoking”, “CAD CAM”, “brushing”, “rough”, “hardness”, combinados entre si pelo operador booleano “AND”, na base de dados PubMed nos últimos 5 anos. Resultados: De acordo com a pesquisa, foram encontrados 625 artigos e selecionados 12 estudos in vitro. 5 estudos concluíram que as restaurações cerâmicas CAD/CAM apresentaram estabilidade de cor e de rugosidade da superfície, após escovação simulada e termociclagem.  4 estudos observaram que a escovação simulada e algumas bebidas aumentaram significativamente a rugosidade superficial da cerâmica de dissilicato de lítio. 3 estudos inferiram que a rugosidade superficial e a microdureza podem ser influenciadas pelos tratamentos de superfícies. Considerações finais: As cerâmicas de dissilicato de lítio CAD/CAM possuem propriedades satisfatórias em relação a sua resistência e estética, após exposição à fumaça do cigarro, associada ou não com a escovação.

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