Fatigue failure load of feldspathic ceramic crowns after hydrofluoric acid etching at different concentrations

SUMMARY The aim of this study was to evaluate the effect of etching, with different hydrofluoric acid concentrations at the intaglio surface of feldspathic ceramic inlays, on the fatigue failure load of restored premolars. A total of 60 upper premolars were embedded in plastic cylinders with acrylic resin (up to 3 mm below the cement-enamel junction) and prepared using a device specially designed for that purpose. Teeth were randomly assigned to three groups (n=20): HF1, HF5, and HF10 (etching with hydrofluoric acid for 60 seconds at concentrations of 1%, 5%, and 10%, respectively). Preparations were scanned and restorations were milled by a computer-aided design / computer-aided manufacturing system. The inner surfaces of the inlays were etched and received an application of a silane coupling agent; the dentin and enamel were treated appropriately for the luting system (RelyX ARC, 3M-ESPE). The restorations were cemented and the fatigue failure load (in N) was determined using the staircase method (10 Hz; 105 cycles in each step). The initial load (585.5 N) was applied on the slopes of the cusps (labial and palatal/lingual, simultaneously) through a cylinder attached to the test machine (Instron ElectroPuls E3000). The tested samples were analyzed under a stereomicroscope for failure analysis. Fatigue data were analyzed by one-way analysis of variance. There was no statistical difference among the fatigue failure loads (in N): HF1 (448.5±79.1), HF5 (360.7±55.4), and HF10 (409.5±121.1). Regarding the fracture mode, there was a predominance of interfacial fracture (50%), followed by cusp fracture (34.6%). It may be concluded that the etching with hydrofluoric acid at the tested concentrations (1%, 5%, and 10%) does not influence the fatigue failure load of feldspathic ceramic inlays cemented on premolars.

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Fatigue Failure Load of a Bonded Simplified Monolithic Feldspathic Ceramic: Influence of Hydrofluoric Acid Etching and Thermocycling

Operative Dentistry ◽

10.2341/19-069-l ◽

2020 ◽

Vol 45 (1) ◽

pp. E21-E31 ◽

Cited By ~ 1

Author(s):

LF Guilardi ◽

GKR Pereira ◽

AS Vallau ◽

IA Silva ◽

JC Giordani ◽

...

Keyword(s):

Fatigue Failure ◽

Fatigue Resistance ◽

Hydrofluoric Acid ◽

Failure Load ◽

Statistical Tests ◽

Resin Cement ◽

Ceramic Surface ◽

Adhesive Cementation ◽

Ceramic Restorations ◽

O 10

SUMMARY Objective: To evaluate the effect of hydrofluoric acid (HF) etching and thermocycling (Tc) on fatigue failure load of feldspathic ceramic restorations cemented with two resin cements. Methods: Disc-shaped feldspathic ceramic (Vitablocs Mark II; Ø=10 mm, 1.0-mm thick) and G10 epoxy resin (Ø=10 mm, 2.5-mm thick) specimens were made and randomly allocated considering three factors: ceramic etching (ie, with vs without 10% HF plus silane application), resin cement (ie, self-adhesive [RelyX U200; U200] or conventional [Multilink Automix; MA]), and Tc (ie, with vs without 5-55°C/12,000 cycles). Adhesive cementation followed each manufacturer's instructions. The fatigue test (n=20) was based on the staircase approach (250,000 cycles; 20 Hz). Contact angle, surface topography, and fractography analysis were also executed. Specific statistical tests were employed for each outcome (α=0.05). Results: The interaction of HF and Tc factors decreased the fatigue resistance for both cements (U200 542.63>U200/HF-Tc 495.00; MA 544.47>MA/HF-Tc 506.84). Comparing the cements associated with HF or Tc, there was statistical superiority for MA (U200-Tc 537.37<MA-Tc 561.32; U200/HF 535.79<MA/HF 557.11), and no statistical difference was detected when only cement type or its association with HF-Tc was compared (U200 542.63=MA 544.47; U200/HF-Tc 495.00=MA/HF-Tc 506.84). The fracture always originated from defects at the ceramic-intaglio surface as radial cracks. Conclusion: HF etching plus silane agent increased the ceramic surface free energy and its wettability, but it did not provide better results in terms of fatigue resistance compared with silane agent application only. The association of HF etching and aging significantly reduced the fatigue resistance of the material, regardless of the resin cement used.

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Fatigue failure load of zirconia-reinforced lithium silicate glass ceramic cemented to a dentin analogue: Effect of etching time and hydrofluoric acid concentration

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2017.09.028 ◽

2018 ◽

Vol 77 ◽

pp. 375-382 ◽

Cited By ~ 21

Author(s):

Jaiane Bandoli Monteiro ◽

Marcelo Gallo Oliani ◽

Luis Felipe Guilardi ◽

Catina Prochnow ◽

Gabriel Kalil Rocha Pereira ◽

...

Keyword(s):

Silicate Glass ◽

Fatigue Failure ◽

Acid Concentration ◽

Glass Ceramic ◽

Hydrofluoric Acid ◽

Failure Load ◽

Lithium Silicate ◽

Etching Time ◽

Lithium Silicate Glass

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The effect of hydrofluoric acid concentration on the fatigue failure load of adhesively cemented feldspathic ceramic discs

Dental Materials ◽

10.1016/j.dental.2018.01.010 ◽

2018 ◽

Vol 34 (4) ◽

pp. 667-675 ◽

Cited By ~ 14

Author(s):

Andressa B. Venturini ◽

Catina Prochnow ◽

Gabriel K.R. Pereira ◽

Arie Werner ◽

Cornelis J. Kleverlaan ◽

...

Keyword(s):

Fatigue Failure ◽

Acid Concentration ◽

Hydrofluoric Acid ◽

Failure Load

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Laser Use in Creating Orthodontic Adhesion to Ceramic Surfaces

Applied Sciences ◽

10.3390/app11062512 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2512

Author(s):

Anca Labunet ◽

Andreea Kui ◽

Sorina Sava

Keyword(s):

Hydrofluoric Acid ◽

Surface Preparation ◽

Good Alternative ◽

Ceramic Surface ◽

Ti:Sapphire Lasers ◽

Ceramic Surfaces ◽

Golden Standard ◽

Laser Systems ◽

Ceramic Crowns

Orthodontists must sometimes bond attachments to ceramic crowns, by using one of the surface preparations available, such as sandblasting or acid etching with hydrofluoric acid. Research shows that different laser systems may also be used for this purpose. The aim of this review is to determine which laser type and modality of use is the most effective in increasing shear bond strength of brackets bonded to ceramic surfaces. Two independent researchers studied the current literature 1990–2018 and selected original articles focusing on in vitro research on laser use for ceramic surface preparation for bonding metallic or ceramic attachments. Twelve articles have met the criteria and have been thoroughly revised, focusing on 2 fractional, Nd:Yag, Er:Yag, femtosecond and Ti:Sapphire lasers. There is little difference shown by the current studies between ceramic types and information on orthodontic bonding to non-feldspathic ceramics is scarce. Femtosecond laser is a good alternative to classical surface preparation with hydrofluoric acid. Nd:Yag laser is more suitable for surface preparation of ceramics than different types of Er:Yag lasers. Difference in laser power may achieve different results, but the golden standard for lasers use has not been found. Laser usage does not obtain the same results as hydrofluoric acid and cannot, so far, eliminate its application.

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Four chemical methods of porcelain conditioning and their influence over bond strength and surface integrity

Dental Press Journal of Orthodontics ◽

10.1590/2176-9451.20.4.051-056.oar ◽

2015 ◽

Vol 20 (4) ◽

pp. 51-56 ◽

Cited By ~ 5

Author(s):

João Paulo Fragomeni Stella ◽

Andrea Becker Oliveira ◽

Lincoln Issamu Nojima ◽

Mariana Marquezan

Keyword(s):

Phosphoric Acid ◽

Bond Strength ◽

Surface Integrity ◽

Hydrofluoric Acid ◽

Shear Bond Strength ◽

Testing Machine ◽

Acid Etching ◽

Ceramic Surface ◽

Surface Conditioning ◽

Phosphoric Acid Etching

OBJECTIVE: To assess four different chemical surface conditioning methods for ceramic material before bracket bonding, and their impact on shear bond strength and surface integrity at debonding.METHODS: Four experimental groups (n = 13) were set up according to the ceramic conditioning method: G1 = 37% phosphoric acid etching followed by silane application; G2 = 37% liquid phosphoric acid etching, no rinsing, followed by silane application; G3 = 10% hydrofluoric acid etching alone; and G4 = 10% hydrofluoric acid etching followed by silane application. After surface conditioning, metal brackets were bonded to porcelain by means of the Transbond XP system (3M Unitek). Samples were submitted to shear bond strength tests in a universal testing machine and the surfaces were later assessed with a microscope under 8 X magnification. ANOVA/Tukey tests were performed to establish the difference between groups (α= 5%).RESULTS: The highest shear bond strength values were found in groups G3 and G4 (22.01 ± 2.15 MPa and 22.83 ± 3.32 Mpa, respectively), followed by G1 (16.42 ± 3.61 MPa) and G2 (9.29 ± 1.95 MPa). As regards surface evaluation after bracket debonding, the use of liquid phosphoric acid followed by silane application (G2) produced the least damage to porcelain. When hydrofluoric acid and silane were applied, the risk of ceramic fracture increased.CONCLUSIONS: Acceptable levels of bond strength for clinical use were reached by all methods tested; however, liquid phosphoric acid etching followed by silane application (G2) resulted in the least damage to the ceramic surface.

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Acid Etching as Surface Treatment Method for Luting of Glass-Ceramic Restorations, part 1: Acids, Application Protocol and Etching Effectiveness

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2018.147 ◽

2018 ◽

Vol 6 (3) ◽

pp. 568-573 ◽

Cited By ~ 4

Author(s):

Emilija Barjaktarova-Valjakova ◽

Anita Grozdanov ◽

Ljuben Guguvcevski ◽

Vesna Korunoska-Stevkovska ◽

Biljana Kapusevska ◽

...

Keyword(s):

Surface Treatment ◽

Glass Ceramic ◽

Hydrofluoric Acid ◽

Treatment Method ◽

Acid Etching ◽

Etching Time ◽

Ceramic Surface ◽

Adhesive Luting ◽

Ceramic Restorations ◽

Etching Effect

AIM: The purpose of this review is to represent acids that can be used as surface etchant before adhesive luting of ceramic restorations, placement of orthodontic brackets or repair of chipped porcelain restorations. Chemical reactions, application protocol, and etching effect are presented as well.STUDY SELECTION: Available scientific articles published in PubMed and Scopus literature databases, scientific reports and manufacturers' instructions and product information from internet websites, written in English, using following search terms: “acid etching, ceramic surface treatment, hydrofluoric acid, acidulated phosphate fluoride, ammonium hydrogen bifluoride”, have been reviewed.RESULTS: There are several acids with fluoride ion in their composition that can be used as ceramic surface etchants. The etching effect depends on the acid type and its concentration, etching time, as well as ceramic type. The most effective etching pattern is achieved when using hydrofluoric acid; the numerous micropores and channels of different sizes, honeycomb-like appearance, extruded crystals or scattered irregular ceramic particles, depending on the ceramic type, have been detected on the etched surfaces.CONCLUSION: Acid etching of the bonding surface of glass - ceramic restorations is considered as the most effective treatment method that provides a reliable bond with composite cement. Selective removing of the glassy matrix of silicate ceramics results in a micromorphological three-dimensional porous surface that allows micromechanical interlocking of the luting composite.

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