scholarly journals Effect of Different Silane-Containing Solutions on Glass-Ceramic/ Cement Bonding Interacting with Dual-Cure Resin Cements

2015 ◽  
pp. 87
Author(s):  
Fabián Murillo Gómez ◽  
Mário Fernando De Góes
Keyword(s):  
Glass Ceramic ◽  
Resin Cement ◽  
Cohesive Failure ◽  
Resin Cements ◽  
Sem Images ◽  
Universal Adhesive ◽  
Mean Values ◽  
Treatment Groups ◽  
Acid Gel ◽  
To Receive

<p><span>The aim of this study is to determine the effect of different silane-containing solutions on ceramic-cement bonding and their interaction with different dual-cure resin cements. Forty five glass- ceramic plaques (IPS e.max CAD®) were sandblasted with aluminum oxide for 5s, etched with 10% hydrofluoric acid gel (HF) for 20s and then divided in three groups of 15 each to be treated with different silane-containing solutions: RelyX Ceramic Primer® (AS), Scotchbond Universal® (SU), Clearfil Ceramic Primer® (CP). Then each group was divided in five groups of three plaques to receive the following dual-cure resin cements: Conventional: RelyX Ultimate (RU), RelyX ARC (AR), VarioLink II (VL); and two self-adhesive: RelyX UNICEM 2 (U2), and BiFix (BF). Eight cement cylinders of each cement were distributed on each plaque and polymerized, summarizing 24 cylinders per group. After 24 h storage in relative humidity at 37°C, each cylinder was subjected to a microshear testing. Failure mode was analyzed using scanning electron microscopy (SEM). Data were statistically analyzed with two-way ANOVA (resin cement and silane ) and Tukey test (p≤0.05). Both factors significantly influenced the results and also interaction between them was detected (p=0.0001). μSBS was significantly higher when ceramic was treated with AS for all cements. Most of cements showed no statistically different means when treated with SU and CP, except BF-SU and AR-CP that showed significantly lower means within their treatment groups. Some incomplete polymerization areas were observed in SEM images for those cases. Cohesive failure in resin cement type was predominant with higher results while adhesive with lower results. The sole silane solution improved better bonding than the universal adhesive and the ceramic primer. In general, universal adhesive and ceramic primer produced acceptable mean values and they were statistically comparable. Compatibility between silane solutions and dual-cure resin cements may be material dependent. </span></p>

scholarly journals Analysis of Self-Adhesive Resin Cement Microshear Bond Strength on Leucite-Reinforced Glass-Ceramic with/without Pure Silane Primer or Universal Adhesive Surface Treatment

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Yoon Lee ◽  
Jae-Hoon Kim ◽  
Jung-Soo Woo ◽  
Young-Ah Yi ◽  
Ji-Yun Hwang ◽  
...  
Keyword(s):  
Bond Strength ◽  
Glass Ceramic ◽  
Glass Ceramics ◽  
Positive Control ◽  
Negative Control ◽  
Resin Cement ◽  
Cohesive Failure ◽  
Universal Adhesive ◽  
Adhesive Resin ◽  
Microshear Bond Strength

Objective. To evaluate the microshear bond strength (μSBS) of self-adhesive resin (SA) cement on leucite-reinforced glass-ceramic using silane or universal adhesive.Materials and Methods. Ceramic blocks were etched with 9.5% hydrofluoric acid and divided into three groups (n=16): (1) negative control (NC) without treatment; (2) Single Bond Universal (SBU); (3) RelyX Ceramic Primer as positive control (PC). RelyX Unicem resin cement was light-cured, andμSBS was evaluated with/without thermocycling. TheμSBS was analyzed using one-way analysis of variance. The fractured surfaces were examined using stereomicroscopy and scanning electron microscopy (SEM).Results. Without thermocycling,μSBS was highest for PC (30.50 MPa ± 3.40), followed by SBU (27.33 MPa ± 2.81) and NC (20.18 MPa ± 2.01) (P<0.05). Thermocycling significantly reducedμSBS in SBU (22.49 MPa ± 4.11) (P<0.05), but not in NC (20.68 MPa ± 4.60) and PC (28.77 MPa ± 3.52) (P>0.05). PC and NC predominantly fractured by cohesive failure within the ceramic and mixed failure, respectively.Conclusion. SBU treatment improvesμSBS between SA cement and glass ceramics, but to a lower value than PC, and the improvement is eradicated by thermocycling. NC exhibited the lowestμSBS, which remained unchanged after thermocycling.

scholarly journals Effect of Different Silane Treatments on Long-Term Bonding Between Non-Etched Glass-Ceramic and Resin Cement

2017 ◽  
Vol 19 (2) ◽  
pp. 33 ◽  
Author(s):  
Fabián Murillo Gómez DDS, MSc ◽  
Mario F. De Goes DDS, MSc, PhD
Keyword(s):  
Glass Ceramic ◽  
Ceramic Materials ◽  
Positive Control ◽  
Negative Control ◽  
Resin Cement ◽  
Ceramic Surface ◽  
Cohesive Failure ◽  
Universal Adhesive ◽  
Long Term Storage

The present study evaluated the bond strength between glass-ceramic and resin cement, using different silane treatments, performing no previous hydrofluoric acid (HF) etching on ceramic surface, after short- and long- term storage. One hundred and eighty glass-ceramic plaques (IPS e.max CAD®) were polished and divided into six groups (n=30) to receive different silane treatments: (1) RCP-RelyX Ceramic Primer® (one-bottle silane), (2) RCP+SB-RelyX Ceramic Primer and Adper Singlebond2® (silane plus separated adhesive), (3) SBU-Scotchbond Universal® (silane-containing universal adhesive), (4) CP-Clearfil Ceramic Primer® (silane/MDP primer), (5) NC-no-silane (negative control) and (6) PC-Previous HF etching (5%, 20s) plus RelyX Ceramic Primer® (positive control). Two resin cement cylinders (Rely X Ultimate®) were built on each plaque. Each group was divided into two sub-groups to be stored for 24 hours (24h) or 6 months (6mo) in distilled water at 37°C (n=15). Then microshear (µSBS) testing was performed. Failure mode was analyzed using scanning electron microscopy (SEM). Data were statistically analyzed by two-way ANOVA and Tukey´s test (α=0.05). Both factors and their interaction resulted statistically significant (p≤0.05). PC obtained the highest µSBS values (in MPa) at both storage times (24h: 28.11±2.44; 6mo: 19.10±3.85). After 24h storage, groups RCP+SB (10.86±3.62), SBU (8.37±4.33) and CP (8.05±3.62) were not statistically different from NC (8.00±2.51); only RCP (19.73±4.63) and PC obtained higher values. After 6 months, only PC showed higher values than NC (0.04±0.01). Cohesive failure in resin cement was more prevalent for RCP-24h and PC, while adhesive failure was more frequent among all other groups.  Clinical relevance: None of the commercially available silane primers tested, improve long- term ceramic/cement bonding without performing HF etching on ceramic surface. Combination of HF acid and silane, remain as a gold standard treatment for glass-ceramic materials. 

Impact of Silane-containing Universal Adhesive on the Biaxial Flexural Strength of a Resin Cement/Glass-ceramic System

2019 ◽  
Vol 44 (2) ◽  
pp. 200-209 ◽  
Author(s):  
F Murillo-Gómez ◽  
RB Wanderley ◽  
MF De Goes
Keyword(s):  
Flexural Strength ◽  
Glass Ceramic ◽  
Resin Cement ◽  
Weibull Analysis ◽  
Ceramic System ◽  
Universal Adhesive ◽  
Bonded Interface ◽  
Biaxial Flexural Strength ◽  
Digital Caliper ◽  
One Way Anova

SUMMARY The aim of this study was to determine whether using a silane-containing universal adhesive as a silane primer in glass-ceramic/resin cement systems affects biaxial flexural strength (BFS) and bonded interface integrity after loading. Glass-ceramic (IPS e.max CAD, Ivoclar/Vivadent, Schaan, Liechtenstein) disc-shaped specimens (6.5±0.1mm in diameter, 0.5±0.1mm thick) were etched with 5% hydrofluoric acid (HF) for 20 seconds and divided into four groups of 30 specimens, to be treated as follows: 1) One bottle silane primer (RCP); 2) Separate application of silane and adhesive (RCP+SB); 3) Silane-containing universal adhesive (SBU); 4) No treatment (C). After silanization, all specimens were resin cement– coated and polymerized for 40 seconds. Each specimen layer was measured, as well as each assembly's thickness, using a digital caliper and scanning electron microscope (SEM). Specimens were stored for 24 hours and submitted to a BFS test (1.27 mm/min). BFS values were calculated using the bilayer disc-specimen solution. Bonded interfaces were analyzed on fractured fragments using SEM. One-way ANOVA and Tukey tests (α=0.05) were applied, as well as the Weibull analysis. Factor “silane treatment” was statistically significant (p&lt;0.0001). RCP+SB (372.2±29.4 MPa) and RCP (364.2±29.5 MPa) produced significantly higher BFS than did the C (320.7±36.3 MPa) or SBU (338.0±27.1 MPa) groups. No differences were found in the Weibull modulus (m: RCP: 10.1-17.3; RCP+SB: 10.1-17.0; SBU: 12.3-22.4; C: 7.4-12.9). Bonded interface analysis exhibited ceramic-cement separation (SBU, C) and voids within the resin cement layer (all groups). Neither the ceramic/cement system's BFS nor its bonded interface stability were improved by SBU after loading.

scholarly journals The Effect of Hydrofluoric Acid Concentration and Heat on the Bonding to Lithium Disilicate Glass Ceramic

2016 ◽  
Vol 27 (6) ◽  
pp. 727-733 ◽  
Author(s):  
Daniel Sundfeld ◽  
Lourenço Correr-Sobrinho ◽  
Núbia Inocêncya Pavesi Pini ◽  
Ana Rosa Costa ◽  
Renato Herman Sundfeld ◽  
...  
Keyword(s):  
Bond Strength ◽  
Glass Ceramic ◽  
Hydrofluoric Acid ◽  
Lithium Disilicate ◽  
Resin Cement ◽  
Glassy Matrix ◽  
Etching Time ◽  
Sem Images ◽  
Matrix Removal ◽  
Post Hoc

Abstract The aim of this study was to evaluate the effects of hydrofluoric acid (HF) concentration and previous heat treatment (PHT) on the surface morphology and micro-shear bond strength (mSBS) of a lithium disilicate glass ceramic (EMX) to resin cement. One hundred four EMX specimens were randomly assigned to two groups (n=52) according to the HF concentration: 5% and 10%. A new random distribution was made according to the PHTs (n=13): control (no PHT); previously heated HF (70 °C); previously heated EMX surface (85 °C); the combination of heated HF + heated EMX surface. The etching time was set at 20 s. All EMX blocks were silanated and received a thin layer of an unfilled resin. Five resin cement cylinders were made on each EMX surface using Tygon tubes as matrices, and then stored for 24 h at 37 °C. One random etched EMX sample from each group was analyzed using field-emission scanning electron microscopy (FE-SEM). The data were subjected to two-way ANOVA and multiple comparisons were performed using the Tukey post hoc test (a=0.05). For the control groups, 5% HF showed statistically lower mSBS values when compared to 10% HF (p<0.05). PHT increased the mSBS values for 5% HF, yielding statistically similar results to non-PHT 10% HF (p<0.05). FE-SEM images showed increased glassy matrix removal when PHT was applied to HF 5%, but not to the same degree as for 10% HF. PHT has the potential to improve the bond strength of 5% HF concentration on lithium disilicate glass ceramic.

Early Reversal of Rapacuronium with Neostigmine 

1999 ◽  
Vol 91 (1) ◽  
pp. 51-57 ◽  
Author(s):  
Robert Purdy ◽  
David R. Bevan ◽  
Francois Donati ◽  
Lance J. Lichtor
Keyword(s):  
Neuromuscular Block ◽  
Rapid Onset ◽  
Force Of Contraction ◽  
Mean Values ◽  
Neuromuscular Relaxant ◽  
Treatment Groups ◽  
Nitrous Oxide Oxygen ◽  
Train Of Four ◽  
To Receive ◽  
Different Doses

Background Rapacuronium is a rapid-onset, short-acting neuromuscular relaxant. This multiple-center study determined neuromuscular recovery when neostigmine was given 2 or 5 min after rapacuronium. Methods One hundred seventeen patients were randomized to receive two different doses of rapacuronium and to receive neostigmine in two different doses and at two different times. During propofol anesthesia with nitrous oxide, oxygen, and fentanyl, 1.5 or 2.5 mg/kg rapacuronium was given 1 min before tracheal intubation. Neuromuscular block was measured by train-of-four ulnar nerve stimulation every 12 s: The adductor pollicis force of contraction was recorded mechanomyographically. Two or five minutes after rapacuronium was administered, 0.05 or 0.07 mg/kg neostigmine was administered and recovery was compared with that of control patients who received no neostigmine. Results Both doses of rapacuronium produced 100% block in all but one patient, who exhibited 97% block. Neostigmine accelerated recovery in all groups. After 1.5 mg/kg rapacuronium, the time to 25% T1 twitch recovery decreased from a mean of 16 min in control patients to mean values of 8-10 min in the treatment groups: The time to train-of-four ratio of 0.7 decreased from 38 min to 17-19 min. After 2.5 mg/kg rapacuronium, the time to 25% T1 was reduced from 23 min to 11-12 min, and the time to train-of-four ratio of 0.7 decreased from 54 min to 26-32 min. Recovery was not different among the the groups that received different doses and timing of neostigmine. Conclusions Recovery of intense rapacuronium block was accelerated by early neostigmine administration. When given 2 min after rapacuronium, neostigmine was as effective as after 5 min, and 0.05 mg/kg neostigmine was comparable to 0.07 mg/kg neostigmine.

The Effect of Aging and Surface treatments on Micro-shear Bond Strength of Resin Nano-Ceramic Material Using Two Resin Cements

2020 ◽  
Author(s):  
Ayman Mohammed Said
Keyword(s):  
Bond Strength ◽  
Hydrofluoric Acid ◽  
Shear Bond Strength ◽  
Surface Treatments ◽  
Resin Cement ◽  
Acid Etching ◽  
Resin Cements ◽  
Adhesive Resin ◽  
Mean Values ◽  
Adhesive Resin Cement

Purpose: To evaluate the effect of aging and different surface treatments on micro-shear bond strength of two resin cements to resin nano-ceramic composite blocks using an in-vitro study. Materials and methods: Blocks of resin nano-ceramic (Lava Ultimate, 3M, St Paul, Minnesota, USA) were used to prepare eight plates having the following dimensions: (14mm × 12mm × 2mm). After plates preparation they were assigned to two main groups according to the surface treatment applied, either hydrofluoric acid etching and silane or sandblasting and silane. Scanning electron microscope (SEM) was used to analyze the surface topography of the Lava-Ultimate plates before and after application of surface treatments. Two resin cements were used; dual cured adhesive resin cement (Bifix QM, VOCO, Cuxhafen, Germany) and dual cured self-adhesive resin cement (Bifix SE, VOCO, Cuxhafen, Germany) to create a five resin micro-cylinders received on each lava ultimate plate. Ten specimens from each subgroup were tested after 24 hours and the other ten specimens were tested after aging in saline for 6 months. Micro-shear bond strength test was applied until failure. . Multi-factorial ANOVA test and One-way ANOVA followed by pair-wise Tukey’s post-hoc tests were used to analyze the data. Results: Both resin cements showed statistically significant decrease on bond strength after aging. Before aging, both surface treatments with adhesive resin cement showed statistically significant higher micro-shear bond strength mean values than with self-adhesive resin cement. After aging sandblasting showed a statistically significant higher micro-shear bond strength mean values with adhesive resin cement, while hydrofluoric acid etching revealed a statistically non-significant higher values with adhesive resin cement than self-adhesive resin cement. Conclusion: For both surface treatments and resin cements aging had a detrimental effect on micro- shear bond strength.

Effect of Silanization on Microtensile Bond Strength of Different Resin Cements to a Lithium Disilicate Glass Ceramic

2016 ◽  
Vol 17 (2) ◽  
pp. 149-153 ◽  
Author(s):  
Cristina Parise Gré ◽  
Renan C de Ré Silveira ◽  
Shizuma Shibata ◽  
Carlo TR Lago ◽  
Luiz CC Vieira
Keyword(s):  
Bond Strength ◽  
Glass Ceramic ◽  
Hydrofluoric Acid ◽  
Lithium Disilicate ◽  
Resin Cement ◽  
Microtensile Bond Strength ◽  
Resin Cements ◽  
Adhesive Resin ◽  
Silane Coupling ◽  
Adhesive Resin Cement

ABSTRACT Aim This study evaluated the influence of a silane-coupling agent on the bond strength of a self-adhesive cement and a conventional resin cement to a lithium disilicate glass ceramic. Materials and methods A total of eight ceramic blocks were fabricated and divided into four groups (n = 2). In groups 1 and 3, ceramic surfaces were etched with hydrofluoric acid 10% for 20 seconds, rinsed for 30 seconds, and air-dried. One layer of a silane agent was applied onto all ceramic specimens and air-dried for 30 seconds. In groups 2 and 4, ceramic surfaces were etched with hydrofluoric acid, rinsed, and air-dried without application of the silane-coupling agent. The ceramic blocks were bonded to a block of composite with a self-adhesive resin cement or with a conventional resin cement, according to the manufacturer's instructions. After 24 hours in distilled water at 37°C, the specimens were sectioned perpendicular to the bonding interface area to obtain beams with a bonding area of 0.8 mm2 and submitted to a microtensile bond strength test at a crosshead speed of 0.5 mm/min. Data were statistically analyzed with one-way analysis of variance and the Games–Howell post hoc test (p = 0.05). Fractured specimens were examined under optical microscopy at 40× magnification. Results Silanization resulted in higher microtensile bond strength compared to groups without silane. No significant differences were found between the conventional resin cement and the self-adhesive resin cement with silane agent (p = 0.983), and without silane agent (p = 0.877). Conclusion Silanization appears to be crucial for resin bonding to a lithium disilicate-based ceramic, regardless of the resin cement used. The self-adhesive resin cement performed as well as the conventional resin cement. Clinical significance Applying one layer of a silane-coupling agent after etching the ceramic surface with hydrofluoric acid 10% enhanced the bond strength between resin cements and a glass ceramic. How to cite this article Gré CP, de Ré Silveira RC, Shibata S, Lago CTR, Vieira LCC. Effect of Silanization on Microtensile Bond Strength of Different Resin Cements to a Lithium Disilicate Glass Ceramic. J Contemp Dent Pract 2016;17(2):149-153.

scholarly journals Influence of light activation of simplified adhesives on the shear bond strength of resin cements to a leucite-reinforced ceramic

2018 ◽  
Vol 12 (01) ◽  
pp. 003-006 ◽  
Author(s):  
Adilson Yoshio Furuse ◽  
Cassiana Koch Scotti ◽  
Alfredo Llerena-Icochea ◽  
Juliana Fraga Soares Bombonatti ◽  
Gisele Aihara Haragushiku ◽  
...  
Keyword(s):  
Bond Strength ◽  
Glass Ceramic ◽  
Shear Bond Strength ◽  
Analysis Data ◽  
Resin Cement ◽  
Light Activation ◽  
Single Bond ◽  
Resin Cements ◽  
Ceramic Surfaces ◽  
Strength Tests

ABSTRACT Objective This study aims to evaluate the influence of the light activation of simplified adhesives on the shear bond strength of resin cements to a glass-ceramic. Three factors were evaluated: (1) cement in two levels (light cured and dual cured); (2) adhesive in two levels (Single Bond 2 and Single Bond Universal), and (3) light activation in two levels (yes or no). Materials and Methods Thirty-two 1-mm thick slices of a leucite-reinforced glass-ceramic (IPS Empress CAD) were divided into eight groups according to adhesive (Single Bond 2 or Single Bond Universal), cement (AllCem Veneer or AllCem), and light activation of the adhesive before application of the cement (yes or no). Ceramic surfaces were etched for 60 s with 5% hydrofluoric acid, and adhesives were applied. Four cement cylinders were made over each ceramic slice (n = 16) and then submitted to shear bond strength tests. Statistical Analysis Data were analyzed with three-way ANOVA and Tukey (⍺ = 0.05). Results: There were significant differences between adhesives (P < 0.0001) and no differences between cements (P = 0.0763) and light activation (P = 0.4385). No interaction effect occurred (P = 0.05). Single Bond 2 showed higher bond strength than Single Bond Universal. Conclusions: The light activation of the adhesive before the application of the resin cement did not influence the bond strength.

scholarly journals Evaluation of Cements Curing Modes Regarding Microleakage During Cementation of E-max Laminate Veneers

2021 ◽  
Vol 9 (D) ◽  
pp. 155-159
Author(s):  
Waleed Alqahtani ◽  
Rami Mohammed Galal ◽  
Ghada Hamza
Keyword(s):  
Resin Cement ◽  
The Self ◽  
Qualitative Assessment ◽  
Resin Cements ◽  
Adhesive Resin ◽  
Significant Difference ◽  
Blue Stain ◽  
To Receive ◽  
Laminate Veneers ◽  
Descriptive Statistical Analysis

Purpose: The aim of this study is to investigate the effect of the curing modes of two adhesive resin cements (Light cure mode of the Variolink Veneer, the self-cure mode and dual cure mode of the Multilink Automix) on the marginal leakage of lithium disilicate ceramic laminate veneers. Methods: A total number of forty eight extracted natural central incisors were prepared to receive ceramic laminate veneers, constructed using E-max ceramic divided into three groups cemented using three curing modes of two adhesive resin cements {light-cure mode of Variolink Veneer, self-cure mode of Multilink Automix and dual-cure mode of Multilink Automix adhesive resin cements} . Die penetration test was done using the methylene blue stain {qualitative assessment} for testing the die penetration along the tooth/ceramic interface. Results: Descriptive statistical analysis revealed that the self-curing mode recorded the significantly least degree of leakage compared to the light and dual cure modes.  The self-cure mode recorded (0.1±0.3) which was significantly lower than light cure (1.2 ±0.9) and dual cure mode (1.2 ±0.4), there was no statistical significant difference between the later two curing modes. The self-cure mode of the resin cement is considered a more effective method for having the least marginal leakage at the tooth/ceramic interface. There was no difference between the light cure mode and the dual cure mode.

scholarly journals Incorporation of Arginine to Commercial Orthodontic Light-Cured Resin Cements—Physical, Adhesive, and Antibacterial Properties

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4391
Author(s):  
Saulo Geraldeli ◽  
Lucas de Almeida Maia Carvalho ◽  
Isaac Jordão de Souza Araújo ◽  
Maurício Bottene Guarda ◽  
Marcelle M. Nascimento ◽  
...  
Keyword(s):  
Shear Bond Strength ◽  
Testing Machine ◽  
Antibacterial Properties ◽  
In Vitro Study ◽  
Resin Cement ◽  
Preventive Strategy ◽  
Resin Cements ◽  
Mean Values ◽  
Significant Difference

(1) Background: The amino acid arginine is now receiving great attention due to its potential anti-caries benefits. The purpose of this in vitro study was to evaluate the shear bond strength (SBS), ultimate tensile strength (UTS), and antimicrobial potential (CFU) of two arginine-containing orthodontic resin cements. (2) Methods: Forty bovine incisors were separated into four groups (n = 10): Orthocem, Orthocem + arginine (2.5 wt%), Transbond XT, and Transbond XT + arginine (2.5 wt%). The brackets were fixed to the flat surface of the enamel, and after 24 h the SBS was evaluated using the universal testing machine (Instron). For the UTS test, hourglass samples (n = 10) were made and tested in a mini-testing machine (OM-100, Odeme). For the antibacterial test (colony forming unit-CFU), six cement discs from each group were made and exposed to Streptococcus mutans UA159 biofilm for 7 days. The microbiological experiment was performed by serial and triplicate dilutions. The data from each test were statistically analyzed using a two-way ANOVA, followed by Tukey’s test (α = 0.05). (3) Results: The enamel SBS mean values of Transbond XT were statistically higher than those of Orthocem, both with and without arginine (p = 0.02033). There was no significant difference in the SBS mean values between the orthodontic resin cements, either with or without arginine (p = 0.29869). The UTS of the Transbond XT was statistically higher than the Orthocem, but the addition of arginine at 2.5 wt% did not influence the UTS for either resin cement. The Orthocem + arginine orthodontic resin cement was able to significantly reduce S. mutans growth, but no difference was observed for the Transbond XT (p = 0.03439). (4) Conclusion: The incorporation of arginine to commercial orthodontic resin cements may be an efficient preventive strategy to reduce bacterial growth without compromising their adhesive and mechanical properties.

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