Color Stability, Translucency, and Wettability of a Lithium Disilicate Dental Ceramics Submitted to Different Surface Treatments

The aim of this study was to evaluate the efficacy of different surface conditioning methods on the microtensile bond strength of a restorative composite repair in three types of dental ceramics: lithium disilicate-reinforced, leucite-reinforced and feldspathic. Twelve blocks were sintered for each type of ceramic (n=3) and stored for 3 months in distilled water at 37 °C. The bonding surface of ceramics was abraded with 600-grit SiC paper. Surface treatments for each ceramic were: GC (control) - none; GDB - diamond bur #30 µm; GHF - hydrofluoric acid (10%); GT- tribochemical silica coating (45-μm size particles). Treatments were followed by cleaning with phosphoric acid 37% for 20 s + silane + adhesive. The composite resin was used as restorative material. After repair, samples were subjected to thermocycled ageing (10,000 cycles between 5 °C and 55 °C for 30 s). Thereafter, the samples were sectioned into 1.0 mm2 sticks and tested for microtensile bond strength with 0.5 mm/min crosshead speed. Data were compared by two-way ANOVA and Tukey's test (α=0.05). The superficial wear with diamond bur proved to be suitable for feldspathic porcelain and for leucite-reinforced glass ceramic while hydrofluoric acid-etching is indicated for repairs in lithium disilicate-reinforced ceramic; tribochemical silica coating is applicable to leucite-reinforced ceramic. Predominance of adhesive failures was observed (>85% in all groups). In conclusion, the success of surface treatments depends on the type of ceramic to be repaired.

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Effect of surface treatments on titanium alloy bonding to lithium disilicate glass-ceramics

Journal of Prosthetic Dentistry ◽

10.1016/j.prosdent.2016.04.023 ◽

2016 ◽

Vol 116 (5) ◽

pp. 797-802 ◽

Cited By ~ 7

Author(s):

Nuno Guilherme ◽

Chandur Wadhwani ◽

Cheng Zheng ◽

Kwok-Hung Chung

Keyword(s):

Titanium Alloy ◽

Glass Ceramics ◽

Lithium Disilicate ◽

Surface Treatments ◽

Effect Of Surface

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Effects of Different Polishing Protocols on Lithium Disilicate Ceramics

Brazilian Dental Journal ◽

10.1590/0103-6440201300370 ◽

2015 ◽

Vol 26 (5) ◽

pp. 478-483 ◽

Cited By ~ 3

Author(s):

Tânia Mara da Silva ◽

Ana Carolina Rodrigues Danzi Salvia ◽

Rodrigo Furtado de Carvalho ◽

Eduardo Galera da Silva ◽

Clóvis Pagani

Keyword(s):

Surface Roughness ◽

Lithium Disilicate ◽

Sem Analysis ◽

Surface Treatments ◽

Control Group ◽

Morphological Pattern ◽

Tukey Test ◽

Polishing Procedures ◽

Diamond Paste

Abstract: The aim of this study was to evaluate the effect of different polishing protocols on surface roughness and morphology of lithium disilicate ceramics (IPS e.max CAD). Fifty ceramic bars (2.0x3.0x2.5 mm) were produced and randomly divided into five groups (n=10), according to surface treatments: C: Control; Cer: Ceramaster (60 s); CW: cloth wheel with large-grit diamond (30 s) + cloth wheel with fine-grit diamond paste (30 s); E: grey Exa-Cerapol (20 s) + pink Exa-Cerapol (20 s) + Cerapol Super (20 s); F: Felt wheel with large-grit diamond paste (30 s) + Felt wheel with fine-grit diamond paste (30 s). The samples were evaluated quantitatively for surface roughness (Ra) and qualitatively by SEM, at different moments: initial (prior to roughening), after roughening and after polishing procedures. Ra means were submitted to two-way ANOVA and Tukey test (p<0.05). After the different polishing protocols, no statistically significant differences were observed between the Cer and E groups (p=0.6347), E and CW groups (p=0.1366), and CW and FW groups (p=0.5433). Comparing different stages in the same group, it was possible to observe that CW (p<0.0001) and FW groups (p<0.0001) showed significant differences. SEM analysis revealed that both Cer and E groups exhibited a surface morphological pattern similar to that of control group. All polishing systems were effective in reducing the surface roughness of the studied ceramic type.

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Effect of Hydrothermal Aging and Beverages on Color Stability of Lithium Disilicate and Zirconia Based Ceramics

Medicina ◽

10.3390/medicina55110749 ◽

2019 ◽

Vol 55 (11) ◽

pp. 749 ◽

Cited By ~ 1

Author(s):

Satheesh B. Haralur ◽

Noura Raqe S. Alqahtani ◽

Fatimah Alhassan Mujayri

Keyword(s):

Green Tea ◽

In Vitro Study ◽

Color Stability ◽

Lithium Disilicate ◽

Color Difference ◽

Hydrothermal Aging ◽

Monolithic Zirconia ◽

Post Hoc ◽

Coloring Agents

Background and aim: All-ceramic prosthesis is widely used in modern dental practice because of its improved physico-mechanical and optical properties. These restorations are exposed to coloring agents from various nutrition and beverages in the oral cavity. Long-term color stability is critical for the success of these restorative materials. The purpose of this in vitro study was to assess the effect of common beverages and mouthwash on the color stability of lithium disilicate (LD), monolithic zirconia (MZ) and bilayer zirconia (BZ) surfaces. Material and methods: Thirty disc-shaped specimens from each material were fabricated; each group was subdivided (n = 10) according to coffee, green tea and chlorhexidine immersion solutions. The baseline color of ceramic discs was recorded according to the CIE L*a*b* system with a portable spectrophotometer. The second measurement was recorded after 3000 thermocycling and immersion in coloring agents for 7 days. The mean color difference was calculated and data were compared with Kruskal-Wallis and Mann-Whitney post hoc tests (0.05). Results: ΔE values for LD with the immersion of coffee, tea, and Chlorhexidine gluconate (CHG) were 1.78, 2.241 and 1.58, respectively. Corresponding ΔE values for MZ were 5.60, 5.19, and 4.86; marginally higher than the clinically acceptable level of 3.5. Meanwhile, BZ showed better color stability compared to MZ with ΔE values of 4.22, 2.11 and 1.43. Conclusion: Among the ceramics evaluated, LD ceramic was found to be more color stable, while MZ ceramics displayed a higher susceptibility to discoloration. MZ and BZ ceramic colors were significantly altered with coffee immersion, while LD ceramics were more affected by green tea.

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Color stability of polymer‐infiltrated‐ceramics compared with lithium disilicate ceramics and composite

Journal of Esthetic and Restorative Dentistry ◽

10.1111/jerd.12525 ◽

2019 ◽

Vol 32 (1) ◽

pp. 43-50 ◽

Cited By ~ 4

Author(s):

Aida Seyidaliyeva ◽

Stefan Rues ◽

Zinonas Evagorou ◽

Alexander J. Hassel ◽

Peter Rammelsberg ◽

...

Keyword(s):

Color Stability ◽

Lithium Disilicate

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Effect of Thermocycling, Surface Treatments and Microstructure on the Optical Properties and Roughness of CAD-CAM and Heat-Pressed Glass Ceramics

Materials ◽

10.3390/ma13020381 ◽

2020 ◽

Vol 13 (2) ◽

pp. 381 ◽

Cited By ~ 6

Author(s):

Roxana-Diana Vasiliu ◽

Sorin Daniel Porojan ◽

Mihaela Ionela Bîrdeanu ◽

Liliana Porojan

Keyword(s):

Surface Roughness ◽

Optical Properties ◽

Glass Ceramic ◽

Glass Ceramics ◽

Lithium Disilicate ◽

Ceramic Materials ◽

Surface Treatments ◽

Lithium Silicate ◽

Before And After ◽

Cad Cam

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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Wear Characteristics of Dental Ceramic CAD/CAM Materials Opposing Various Dental Composite Resins

Materials ◽

10.3390/ma12111839 ◽

2019 ◽

Vol 12 (11) ◽

pp. 1839 ◽

Cited By ~ 2

Author(s):

Bora Gwon ◽

Eun-Bin Bae ◽

Jin-Ju Lee ◽

Won-Tak Cho ◽

Hyun-Young Bae ◽

...

Keyword(s):

Weight Loss ◽

Composite Resin ◽

Lithium Disilicate ◽

Composite Resins ◽

Dental Composite ◽

Dental Ceramics ◽

Wear Properties ◽

Dental Ceramic ◽

Dental Composite Resins ◽

Cad Cam

The aim of this study was to evaluate the wear properties of opposed dental ceramic restorative CAD/CAM materials and several posterior direct restorative composite resins. Three kinds of dental ceramics CAD/CAM materials (monolithic zirconia, lithium disilicate, leucite) and four dental composite resins—that is, MI Gracefil, Gradia Direct P, Estelite Σ Quick, and Filtek Supreme Ultra—were used in this study. For each of the 12 groups (three ceramics × four composite resins), five each of a canine-shaped ceramic specimen and a cuboidal shape opposing composite resin were prepared. All of the specimens were tested in a thermomechanical loading machine (50 N, 100,000 cycles, 5/55 °C). Wear losses of ceramic specimens and composite resin specimens were evaluated using a three-dimensional profiling system and an electronic scale, respectively. Statistical analyses were performed using the Kruskal–Wallis test and Mann–Whitney U test with Bonferroni’s correction. Zirconia showed significantly less volumetric loss than lithium disilicate or leucite regardless of composite resin type (p > 0.05/3 = 0.017), and that Estelite Σ Quick showed significantly more weight loss than Filtek Supreme Ultra, MI Gracefil, or Gradia Direct P regardless of ceramic type (p > 0.05/6 = 0.083). Zirconia showed less volumetric loss than lithium disilicate or leucite. Some composite resins opposing ceramics showed considerable weight loss.

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Influence of Surface Treatment on Strength Distribution of Vita VMK 68 Dental Porcelains

Advances in Materials Science and Engineering ◽

10.1155/2013/128065 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7

Author(s):

Serkan Nohut ◽

Ahmet Tasdemir ◽

Suleyman Aykut Korkmaz

Keyword(s):

Distribution Function ◽

Weibull Distribution ◽

Statistical Model ◽

Surface Treatment ◽

Goodness Of Fit ◽

Strength Distribution ◽

Surface Treatments ◽

Bending Test ◽

Dental Ceramics ◽

Weibull Distribution Function

Weibull distribution function is the most commonly used statistical model for the investigation of mechanical properties of dental ceramics and design process with dental ceramics. However, it is still unclear whether the Weibull distribution function is the most appropriate function for fitting the strength data of dental ceramics with different surface treatments. In this paper, three-point bending test results of feldspathic body porcelain (Vita VMK 68) specimens with four different surface treatments are analysed. According to goodness-of-fit tests (Anderson-Darling test, Kolmogorov-Smirnov test, and Akaike information criterion), it is shown that the type of surface treatment has an important influence on deviation of strength distribution from perfect Weibull statistics. It is concluded that estimation of the most suitable statistical model for Vita VMK 68 is not only a material-dependent but also a process-dependent (machining of the specimens) procedure.

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Ceramic Fragments and Metal-free Full Crowns: A Conservative Esthetic Option for Closing Diastemas and Rehabilitating Smiles

Operative Dentistry ◽

10.2341/12-225-t ◽

2013 ◽

Vol 38 (6) ◽

pp. 567-571 ◽

Cited By ~ 13

Author(s):

ME Miranda ◽

KA Olivieri ◽

FJ Rigolin ◽

RT Basting

Keyword(s):

Computer Aided Design ◽

Color Stability ◽

Dental Ceramics ◽

Metal Free ◽

Anterior Teeth ◽

Computer Aided ◽

Adhesive Cementation ◽

Ceramic Crowns ◽

Tooth Preparation ◽

Aided Design

SUMMARY Dental ceramics make it possible to restore anterior teeth that have been esthetically compromised, presenting a high resistance to wear, biocompatibility, color stability, and low thermal conductivity. The development of different types of ceramic and techniques for adhesive cementation have made it possible to produce more conservative restorations without involving the healthy dental structure and with minimally invasive preparation, such as the bonding of ceramic fragments. The purpose of this article is to describe a clinical case in which diastemas were closed by using nanofluorapatite ceramic (e.max Ceram, Ivoclar-Vivadent) fragments on teeth 7 and 10 with minimal tooth preparation and metal-free ceramic crowns (e-max Ceram) reinforced with zirconia copings through a computer-aided design/computer-aided manufacturing system (Lava, 3M-ESPE) on teeth 8 and 9.

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Scanning electron microscope comparative surface evaluation of glazed-lithium disilicate ceramics under different irradiation settings of Nd:YAG and Er:YAG lasers

The Angle Orthodontist ◽

10.2319/062017-408.1 ◽

2017 ◽

Vol 88 (1) ◽

pp. 75-81 ◽

Cited By ~ 3

Author(s):

Josko Viskic ◽

Drazen Jokic ◽

Suzana Jakovljevic ◽

Lana Bergman ◽

Sladana Milardovic Ortolan ◽

...

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Laser Energy ◽

Lithium Disilicate ◽

Surface Roughening ◽

Dental Ceramics ◽

Treated Sample ◽

Power Setting ◽

Dental Lasers ◽

Scanning Electron

ABSTRACT Objective: To evaluate the surface of glazed lithium disilicate dental ceramics after irradiation under different irradiation settings of Nd:YAG and Er:YAG lasers using a scanning electron microscope (SEM). Materials and Methods: Three glazed-press lithium disilicate ceramic discs were treated with HF, Er:YAG, and Nd:YAG, respectively. The laser-setting variables tested were laser mode, repetition rate (Hz), power (W), time of exposure (seconds), and laser energy (mJ). Sixteen different variable settings were tested for each laser type, and all the samples were analyzed by SEM at 500× and 1000× magnification. Results: Surface analysis of the HF-treated sample showed a typical surface texture with a homogenously rough pattern and exposed ceramic crystals. Er:YAG showed no effect on the surface under any irradiation setting. The surface of Nd:YAG-irradiated samples showed cracking, melting, and resolidifying of the ceramic glaze. These changes became more pronounced as the power increased. At the highest power setting (2.25 W), craters on the surface with large areas of melted or resolidified glaze surrounded by globules were visible. However, there was little to no exposure of ceramic crystals or visible regular surface roughening. Conclusions: Neither Er:YAG nor Nd:YAG dental lasers exhibited adequate surface modification for bonding of orthodontic brackets on glazed lithium disilicate ceramics compared with the control treated with 9.5% HF.

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