CAD-CAM milled versus pressed lithium-disilicate monolithic crowns adhesively cemented after distinct surface treatments: Fatigue performance and ceramic surface characteristics

Dental ceramic restorations are widely spread nowadays due to their aesthetics and biocompatibility. In time, the colour and structure of these ceramic materials can be altered by aging processes. How does artificial aging affect the optical and surface roughness of ceramics? This study aims to assess the effect of thermocycling, surface treatments and microstructure upon translucency, opalescence and surface roughness on CAD-CAM and heat-pressed glass-ceramic. Forty-eight samples (1.5 mm thickness) were fabricated from six types of A2 MT ceramic: heat-pressed and milled glass-ceramic (feldspathic, lithium disilicate and zirconia reinforced lithium silicate). The samples were obtained respecting the manufacturer’s instructions. The resulted surfaces (n = 96) were half glazed and half polished. The samples were subjected to thermocycling (10,000 cycles) and roughness values (Ra and Rz), colour coordinates (L*, a*, b*) and microstructural analyses were assessed before and after thermocycling. Translucency (TP) and opalescence (OP) were calculated. Values were statistically analysed using ANOVA test (one way). TP and OP values were significantly different between heat-pressed and milled ceramics before and also after thermocycling (p < 0.001). Surface treatments (glazing and polishing) had a significant effect on TP and OP and surface roughness (p < 0.05). The heat-pressed and milled zirconia reinforced lithium silicate glass-ceramic experienced a loss in TP and OP. Ra and Rz increased for the glazed samples, TP and OP decreased for all the samples after thermocycling. Microstructural analyse revealed that glazed surfaces were more affected by the thermocycling and especially for the zirconia reinforced lithium silicate ceramic. Optical properties and surface roughness of the chosen ceramic materials were affected by thermocycling, surface treatments and microstructural differences. The least affected of the ceramics was the lithium disilicate ceramic heat-pressed polished and glazed.

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Influence of CAD/CAM milling, sintering and surface treatments on the fatigue behavior of lithium disilicate glass ceramic

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2020.104133 ◽

2021 ◽

Vol 113 ◽

pp. 104133

Author(s):

Abdur-Rasheed Alao ◽

Richard Stoll ◽

Yu Zhang ◽

Ling Yin

Keyword(s):

Glass Ceramic ◽

Fatigue Behavior ◽

Lithium Disilicate ◽

Surface Treatments ◽

Cad Cam

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Effects of ceramic surface treatments on the bond strength of an adhesive luting agent to CAD–CAM ceramic

Journal of Dentistry ◽

10.1016/j.jdent.2006.09.006 ◽

2007 ◽

Vol 35 (4) ◽

pp. 282-288 ◽

Cited By ~ 28

Author(s):

M. Peumans ◽

K. Hikita ◽

J. De Munck ◽

K. Van Landuyt ◽

A. Poitevin ◽

...

Keyword(s):

Bond Strength ◽

Surface Treatments ◽

Ceramic Surface ◽

Luting Agent ◽

Adhesive Luting ◽

Cad Cam

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Do resin cement viscosity and ceramic surface etching influence the fatigue performance of bonded lithium disilicate glass-ceramic crowns?

Dental Materials ◽

10.1016/j.dental.2021.12.015 ◽

2021 ◽

Author(s):

Kiara Serafini Dapieve ◽

Gabriel Kalil Rocha Pereira ◽

Andressa Borin Venturini ◽

Natália Daudt ◽

André Valcanaia ◽

...

Keyword(s):

Glass Ceramic ◽

Lithium Disilicate ◽

Resin Cement ◽

Fatigue Performance ◽

Ceramic Surface ◽

Surface Etching ◽

Ceramic Crowns

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Influence of thermal and pH cycles on surface characteristics lithium disilicate glass-ceramic dental crowns milled with CAD/CAM process

World Journal of Engineering ◽

10.1108/wje-03-2021-0129 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Yajvinder Singh ◽

Vishal Gulati

Keyword(s):

Surface Roughness ◽

Glass Ceramic ◽

Research Work ◽

Surface Hardness ◽

Surface Characteristics ◽

Lithium Disilicate ◽

Content Type ◽

Cad Cam ◽

Group 3 ◽

Group 2

Purpose The paper aims to evaluate the influence of thermo-chemical cycles of oral fluids on the surface attributes (roughness and microhardness) of lithium disilicate glass-ceramic (LDC) crown restorations manufactured with CAD/CAM technology. Design/methodology/approach There have been 24 LDC crowns manufactured using the CAD/CAM process for their respective preparation dies ply methyl methacrylate (PMMA) of mandibular left second premolar tooth (n = 8 each group). The standard procedure was used to glaze 16 crown samples (Groups 2 and 3).Samples of Group 3 were aged with thermal (563°C and 5563°C) and pH (2–14) cycles. All 24 samples were tested with a Profilometer and a Vicker hardness tester was used for their surface roughness and hardness measurement, respectively. Findings In statistical examination on SPSS Statistics 20 (IBM) software, of surface roughness values (Ra) and Vicker hardness values from different groups, Tukey HSD test was executed in one-way ANOVA (a = 0.05). The means Ra for groups were accordingly Group 3 > Group1 > Group 2 (p < 0.001). Similarly, micro-hardness was in order of Group 2 > Group 1 > Group 3 (p < 0.001). Research limitations/implications The research work does not have any limitations. Originality/value Surrounding temperature and pH significantly impact the surface characteristics of lithium disilicate crown restoration. The study also reveals the inverse relationship between surface roughness and surface hardness parameters. The observed results and facts revealed well in agreement with the past research studies.

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Evaluation of the Surface Characteristics of Dental CAD/CAM Materials after Different Surface Treatments

Materials ◽

10.3390/ma13040981 ◽

2020 ◽

Vol 13 (4) ◽

pp. 981 ◽

Cited By ~ 1

Author(s):

Konstantinos Papadopoulos ◽

Kimon Pahinis ◽

Kyriaki Saltidou ◽

Dimitrios Dionysopoulos ◽

Effrosyni Tsitrou

Keyword(s):

Surface Roughness ◽

Computer Aided Design ◽

Surface Characteristics ◽

Surface Treatments ◽

Control Group ◽

Composition And Structure ◽

Computer Aided ◽

Need To Evaluate ◽

Cad Cam ◽

Materials Used

Computer-aided design/computer-aided manufacturing (CAD/CAM) technology was developed to ensure the sufficient strength of tooth restorations, to improve esthetic restorations with a natural appearance and to make the techniques easier, faster and more accurate. In the view of the limited research on the surface treatments of the CAD/CAM materials and the need to evaluate the ideal surface characteristics of a material to achieve the best adhesion to tooth tissues, this study aimed to investigate the surface roughness and morphology of four different CAD/CAM materials using four different surface treatments. The CAD/CAM materials used in this study were three composites (Shofu Block HC, Lava Ultimate and Brilliant Crios) and a hybrid ceramic (Enamic). The surface of the specimens of each material received one of the following treatments: no surface treatment, sandblasting with 29 μm Al2O3 particles, 9% hydrofluoric acid etching and silane application, and the tribochemical method using CoJet System. Surface roughness was evaluated using optical profilometry, and surface morphology was observed by means of scanning electron microscopy. All surface treatments resulted in higher surface roughness values compared to the control group. Different treatments affected the surface properties of the materials, presumably due to discrepancies in their composition and structure.

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Effects of Surface Treatments, Thermocycling, and Cyclic Loading on the Bond Strength of a Resin Cement Bonded to a Lithium Disilicate Glass Ceramic

Operative Dentistry ◽

10.2341/11-076-l ◽

2013 ◽

Vol 38 (2) ◽

pp. 208-217 ◽

Cited By ~ 68

Author(s):

GB Guarda ◽

AB Correr ◽

LS Gonçalves ◽

AR Costa ◽

GA Borges ◽

...

Keyword(s):

Bond Strength ◽

Glass Ceramic ◽

Hydrofluoric Acid ◽

Lithium Disilicate ◽

Surface Treatments ◽

Resin Cement ◽

Control Group ◽

Ceramic Surface ◽

Microtensile Bond Strength ◽

Ceramic Blocks

SUMMARY Objectives The aim of this present study was to investigate the effect of two surface treatments, fatigue and thermocycling, on the microtensile bond strength of a newly introduced lithium disilicate glass ceramic (IPS e.max Press, Ivoclar Vivadent) and a dual-cured resin cement. Methods A total of 18 ceramic blocks (10 mm long × 7 mm wide × 3.0 mm thick) were fabricated and divided into six groups (n=3): groups 1, 2, and 3—air particle abraded for five seconds with 50-μm aluminum oxide particles; groups 4, 5, and 6—acid etched with 10% hydrofluoric acid for 20 seconds. A silane coupling agent was applied onto all specimens and allowed to dry for five seconds, and the ceramic blocks were bonded to a block of composite Tetric N-Ceram (Ivoclar Vivadent) with RelyX ARC (3M ESPE) resin cement and placed under a 500-g static load for two minutes. The cement excess was removed with a disposable microbrush, and four periods of light activation for 40 seconds each were performed at right angles using an LED curing unit (UltraLume LED 5, Ultradent) with a final 40 second light exposure from the top surface. All of the specimens were stored in distilled water at 37°C for 24 hours. Groups 2 and 5 were submitted to 3,000 thermal cycles between 5°C and 55°C, and groups 3 and 6 were submitted to a fatigue test of 100,000 cycles at 2 Hz. Specimens were sectioned perpendicular to the bonding area to obtain beams with a cross-sectional area of 1 mm2 (30 beams per group) and submitted to a microtensile bond strength test in a testing machine (EZ Test) at a crosshead speed of 0.5 mm/min. Data were submitted to analysis of variance and Tukey post hoc test (p≤0.05). Results The microtensile bond strength values (MPa) were 26.9 ± 6.9, 22.2 ± 7.8, and 21.2 ± 9.1 for groups 1–3 and 35.0 ± 9.6, 24.3 ± 8.9, and 23.9 ± 6.3 for groups 4–6. For the control group, fatigue testing and thermocycling produced a predominance of adhesive failures. Fatigue and thermocycling significantly decreased the microtensile bond strength for both ceramic surface treatments when compared with the control groups. Etching with 10% hydrofluoric acid significantly increased the microtensile bond strength for the control group.

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