scholarly journals Degree of Conversion of a Resin Cement Light-Cured Through Ceramic Veneers of Different Thicknesses and Types

2014 ◽  
Vol 25 (1) ◽  
pp. 38-42 ◽  
Author(s):  
Patrício Runnacles ◽  
Gisele Maria Correr ◽  
Flares Baratto Filho ◽  
Carla Castiglia Gonzaga ◽  
Adilson Yoshio Furuse
Keyword(s):  
Ftir Spectroscopy ◽  
Degree Of Conversion ◽  
Resin Cement ◽  
Resin Cements ◽  
Different Types ◽  
Light Curing ◽  
One Way Anova

During the cementation of ceramic veneers the polymerization of resin cements may be jeopardized if the ceramics attenuate the irradiance of the light-curing device. The aim of this study was to evaluate the effect of different types and thicknesses of ceramic veneers on the degree of conversion of a light-cured resin-based cement (RelyX Veneer). The cement was light-cured after interposing ceramic veneers [IPS InLine, IPS Empress Esthetic, IPS e.max LT (low translucency) and IPS e.max HT (high translucency) - Ivoclar Vivadent] of four thicknesses (0.5 mm, 1.0 mm, 1.5 mm and 2.0 mm). As control, the cement was light-cured without interposition of ceramics. The degree of conversion was evaluated by FTIR spectroscopy (n=5). Data were analyzed with one-way ANOVA and Tukey's test (α=0.05). Significant differences were observed among groups (p<0.001). The degree of conversion was similar to the control for all light-cured groups with interposition of ceramics of 0.5 mm and 1.0 mm (p>0.05). Among 1.5-mm-thick veneers, IPS e.max LT was the only one that showed different results from the control (p<0.05). At the thickness of 2.0 mm, only the IPS e.max LT and HT veneers were able to produce cements with degrees of conversion similar to the control (p>0.05). The degree of conversion of the evaluated light-cured resin cement depends on the thickness and type of ceramics employed when veneers thicker than 1.5 mm are cemented.

Effect of Irradiance and Exposure Duration on Temperature and Degree of Conversion of Dual-Cure Resin Cement for Ceramic Restorations

2018 ◽  
Vol 43 (6) ◽  
pp. E280-E287 ◽  
Author(s):  
JS Shim ◽  
SH Han ◽  
N Jha ◽  
ST Hwang ◽  
W Ahn ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Exposure Duration ◽  
Near Infrared ◽  
Degree Of Conversion ◽  
Resin Cement ◽  
Resin Cements ◽  
Digital Thermometer ◽  
Light Curing ◽  
Ceramic Restorations

SUMMARY This study investigated the effects of irradiance and exposure duration on dual-cured resin cements irradiated through ceramic restorative materials. A single light-curing unit was calibrated to three different irradiances (500, 1000, and 1500 mW/cm2) and irradiated to three different attenuating materials (transparent acryl, lithium disilicate, zirconia) with 1-mm thicknesses for 20 or 60 seconds. The changes in irradiance and temperature were measured with a radiometer (or digital thermometer) under the attenuating materials. The degree of conversion (DC) of dual-cure resin cement after irradiation at different irradiances and exposure durations was measured with Fourier transform near infrared spectroscopy. Two-way analysis of variance revealed that irradiance (p&lt;0.001) and exposure duration (p&lt;0.001) significantly affected temperature and DC. All groups showed higher DCs with increased exposure times (p&lt;0.05), but there were no statistically significant differences between the groups irradiated with 1000 mW/cm2 and 1500 mW/cm2 (p&gt;0.05). Higher-intensity irradiances yielded higher temperatures (p&lt;0.05), but exposure time did not affect temperature when materials were irradiated at 500 mW/cm2 (p&gt;0.05).

scholarly journals Degree of Conversion and Mechanical Properties of Resin Cements Cured Through Different All-Ceramic Systems

2015 ◽  
Vol 26 (5) ◽  
pp. 484-489 ◽  
Author(s):  
Camila de Carvalho Almança Lopes ◽  
Renata Borges Rodrigues ◽  
André Luis Faria e Silva ◽  
Paulo Cézar Simamoto Júnior ◽  
Carlos José Soares ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Indentation Test ◽  
Degree Of Conversion ◽  
Resin Cement ◽  
Resin Cements ◽  
Mean Values ◽  
Halogen Light ◽  
All Ceramic ◽  
Light Curing ◽  
Better Than

Abstract: The aim of this study was to verify the degree of conversion (DC), Vickers microhardness (VH) and elastic modulus (E) of resin cements cured through different ceramic systems. One 1.5-mm-thick disc of each ceramic system (feldspathic, lithium dissilicate and zircônia veneered with feldspathic) was used. Three dual-cured (Allcem, Variolink II and RelyX U200) and one chemically-cured (Multilink) resin cements were activated through ceramic discs. For dual-cured resin cements was used a conventional halogen light-curing unit (Optilux 501 at 650 mW/cm2 for 120 s). Samples cured without the ceramic disc were used as control. The samples were stored at 37 °C for 24 h. ATR/FTIR spectrometry was used to evaluate the extent of polymerization in the samples (n=5). Micromechanical properties - VH and E - of the resin cements (n=5) were measured with a dynamic indentation test. Data were statistically analyzed with two-way ANOVA, Tukey's test and Pearson's correlation (α=0.05). DC was affected only by the type of resin cement (p=0.001). For VH, significant interaction was detected between resin cement and ceramic (p=0.045). The dual-cured resin cements showed no significant differences in mean values for E and significantly higher values than the chemically-cured resin cement. The degree of conversion and the mechanical properties of the evaluated resin cements depend on their activation mode and the type of ceramics used in 1.5 mm thickness. The dual-cured resin cements performed better than the chemically-cured resin cement in all studied properties.

Effect of LED Light-Curing Spectral Emission Profile on Light-Cured Resin Cement Degree of Conversion

2020 ◽  
Author(s):  
RQ Ramos ◽  
RR Moraes ◽  
GC Lopes
Keyword(s):  
Clinical Relevance ◽  
Degree Of Conversion ◽  
Resin Cement ◽  
Light Activation ◽  
Spectral Emission ◽  
Led Light ◽  
Emission Profile ◽  
Light Curing

Clinical Relevance The use of multipeak LED light-curing guarantees efficiency on light activation of Ivocerin-containing light-cured resin cement.

scholarly journals Effect of Light-Sources and Thicknesses of Composite Onlays on Micro-Hardness of Luting Composites

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6849
Author(s):  
Francesco De Angelis ◽  
Mirco Vadini ◽  
Mario Capogreco ◽  
Camillo D’Arcangelo ◽  
Maurizio D’Amario
Keyword(s):  
High Power ◽  
Resin Composite ◽  
Composite Layer ◽  
Resin Cement ◽  
Specimen Thickness ◽  
Light Sources ◽  
Curing Time ◽  
Resin Cements ◽  
Halogen Light ◽  
Light Curing

The aim of this study was to compare three different light-curing-units (LCUs) and determine their effectiveness in the adhesive cementation of indirect composite restorations when a light-curing resin cement is used. Two resin composites were selected: Enamel Plus HRI (Micerium) and AURA (SDI). Three thicknesses (3 mm, 4 mm and 5 mm) were produced and applied as overlays and underlays for each resin composite. A standardized composite layer was placed between underlay and overlay surfaces. Light curing of the resin-based luting composites was attained through the overlay filters using LCUs for different exposure times. All specimens were allocated to experimental groups according to the overlay thickness, curing unit and curing time. Vickers Hardness (VH) notches were carried out on each specimen. Data were statistically evaluated. The curing unit, curing time and overlay thickness were significant factors capable of influencing VH values. The results showed significantly decreased VH values with increasing specimen thickness (p < 0.05). Significant differences in VH values were found amongst the LCUs for the various exposure times (p < 0.05). According to the results, a time of cure shorter than 80 s (with a conventional quartz–tungsten–halogen LCU) or shorter than 40 s (with a high-power light-emitting diode (LED) LCU) is not recommended. The only subgroup achieving clinically acceptable VH values after a short 20 s curing time included the 3 mm-thick overlays made out of the AURA composite, when the high-power LED LCU unit was used (VH 51.0). Composite thickness has an intense effect on polymerization. In clinical practice, light-cured resin cements may result in insufficient polymerization for high thickness and inadequate times. High-intensity curing lights can attain the sufficient polymerization of resin cements through overlays in a significantly shorter time than conventional halogen light.

scholarly journals Influence of curing mode of resin luting cements on bond strength to dentin

2017 ◽  
Vol 15 (4) ◽  
pp. 258
Author(s):  
Marcelo Giannini ◽  
Andreia Assis Carvalho ◽  
Ariovaldo Stefani ◽  
Wladimir Franco de Sá Barbosa ◽  
Lawrence Gonzaga Lopes
Keyword(s):  
Bond Strength ◽  
Testing Machine ◽  
Resin Cement ◽  
Control Group ◽  
Resin Cements ◽  
Luting Cements ◽  
Halogen Light ◽  
Significant Difference ◽  
Tooth Surfaces ◽  
Light Curing

Self-adhesive, dual-polymerizing resin cements require no treatment to the prepared tooth surfaces before cementation. Aim: The aim of this study was to evaluate the influence of curing mode on bond strength (BS) of three cementing systems to bovine dentin. Methods: The buccal enamel surfaces of 50 bovine incisors were removed to expose dentin and to flat the surface. The teeth were divided into five groups (n=10), which consisted of two resin cements (Multilink and Clearfil SA Cement) that were tested in dual- (halogen light for 40 s) and self-cured modes, and a control (RelyX ARC). Two cylinders of resin cements (1.0 mm X 0.75 mm) were prepared on each bonded dentin surface. After 24h at 37oC, resin cylinders were subjected to micro-shear testing in a universal testing machine (4411/Instron - 0.5 mm/min). Data were statistically analyzed by two-way ANOVA, Tukey and Dunnett`s test (5%). Results: Multilink showed higher BS than those observed on Clearfil SA. Light-curing resulted in higher BS for both Multilink and Clearfil SA. When Multilink was light-cured, no significant difference on BS was demonstrated between it and RelyX ARC. Conclusions: The highest BS values were obtained in control group and light-cured Multilink resin cement.

Lack of Neutralization of 10-MDP Primers by Zirconia May Affect the Degree of Conversion of Dual-cure Resin Cement

2021 ◽  
Vol 46 (1) ◽  
pp. 107-115
Author(s):  
DM De Paula ◽  
AD Loguercio ◽  
A Reis ◽  
S Sauro ◽  
AH Alves ◽  
...  
Keyword(s):  
Bond Strength ◽  
Testing Machine ◽  
Monomer Concentration ◽  
Positive Control ◽  
Degree Of Conversion ◽  
Resin Cement ◽  
Dihydrogen Phosphate ◽  
Resin Cements ◽  
Low Concentrations ◽  
Microshear Bond Strength

Clinical Relevance Use of zirconia primers with a low pH and a high acidic monomer concentration should be employed in combination with dual-cure resin cements that are less sensitive to an acidic environment. Primers with lower 10-MDP concentrations attain better outcomes. SUMMARY Objective: To assess the effects of different concentrations of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) included in experimental ceramic primers on the degree of conversion (DC) and microshear bond strength (μSBS) of a dual-cure resin cement, and on the acidity neutralization potential of zirconia (ZrO2) in comparison to hydroxyapatite (HAp). Methods: Experimental ceramic primers were formulated using 5 wt%, 10 wt%, 20 wt%, or 40 wt% 10-MDP as an acidic functional monomer and camphorquinone (CQ)/amine or 1-phenyl-1,2-propanedione (PPD) as a photoinitiator system. Clearfil Ceramic Primer (Kuraray Dental, Tokyo, Japan) was used as the commercial control. Micro-Raman spectroscopy was used to assess the DC of uncured and light-cured resin cements applied onto primer-treated ZrO2 surfaces. The μSBS and pH of primers were assayed in a universal testing machine and by a digital pH meter (Tec-3MP; Tecnal, Piracicaba, Brazil), respectively. Statistical analysis was performed by one-way analysis of variance (ANOVA) and Tukey’s test (p&lt;0.05). Results: DC was not affected until a concentration of 10% 10-MDP in CQ primer and 5% 10-MDP in PPD primer was reached, when compared with the positive control (p&gt;0.05). Groups 10-MDP 5% in CQ and PPD primers showed the highest μSBS compared with the positive control (p&gt;0.05); however, higher concentrations of 10-MDP induced significant DC and μSBS reduction (p&lt;0.05). HAp neutralized 10-MDP primers, but ZrO2 provided higher acidity to the primers’ pH. Conclusion: 10-MDP monomer should be used in low concentrations in ZrO2 primers to avoid reduction of the polymerization and bond strength of resin cement.

scholarly journals Evaluation of Dual-Cure Resin Cement Polymerization under Different Types and Thicknesses of Monolithic Zirconia

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Pinar Turkoglu ◽  
Deniz Sen
Keyword(s):  
Vickers Hardness ◽  
Resin Cement ◽  
Different Types ◽  
Monolithic Zirconia ◽  
Different Depths ◽  
Post Hoc ◽  
One Way Anova

Purpose. The aim of the present study was to investigate the effects of the type and thickness of the zirconia material on the microhardness of the underlying dual-cure resin cement. Materials and Methods. Eight disk-shaped zirconia specimens with a 4-mm diameter and four varying thicknesses (0.5, 1.0, 1.5, and 2.0 mm) were fabricated from two different monolithic zirconia materials: posterior monolithic zirconia (Prettau) and anterior monolithic zirconia (Prettau Anterior). Dual-cure resin cement specimens with a 4-mm diameter and 5-mm height were prepared using Teflon cylinder molds and activated by light beneath the eight zirconia disks and without any zirconia disk for 20 s (n=12). A total of 108 specimens were embedded in acrylic. Vickers hardness of each specimen was measured at three different depths using a microhardness device with a 50-g load. All data were statistically evaluated using three-way ANOVA, one-way ANOVA, independent samples t-tests, and Bonferroni corrected post hoc tests (α=.05). Results. Dual-cure resin cement’s microhardness was significantly higher for the samples polymerized beneath anterior monolithic zirconia compared to posterior monolithic zirconia. The hardness decreased as the thickness increased for both types of zirconia; the latter was attributed to an attenuated curing efficiency. Conclusion. Microhardness of the dual-cure resin cement is influenced by both the type and the thickness of the monolithic zirconia restoration. Polymerization efficiency for resin cement cured under anterior monolithic zirconia may be superior to cured beneath posterior monolithic zirconia.

scholarly journals Color stability and degree of conversion of a novel dibenzoyl germanium derivative containing photo-polymerized resin luting cement

2020 ◽  
Vol 18 ◽  
pp. 228080002091732 ◽  
Author(s):  
Fahad Alkhudhairy ◽  
Fahim Vohra ◽  
Mustafa Naseem ◽  
Mosa Mohammed Owais ◽  
Abdulmajeed H Bin Amer ◽  
...  
Keyword(s):  
Color Stability ◽  
Color Difference ◽  
Degree Of Conversion ◽  
Resin Cement ◽  
Resin Cements ◽  
Luting Agents ◽  
Multiple Comparison Test ◽  
Luting Cement ◽  
Color Components

Aim: To compare the color stability and degree of conversion (DC) of a resin cement containing a dibenzoyl germanium derivative photo-initiator (Variolink Esthetic) to resin cements containing conventional luting agents. Materials and Method: Spectrophotometry and Fourier transform infrared spectroscopy (FTIR) were used to compare the color stability and DC, respectively, of Variolink Esthetic compared to Calibra, Variolink-N, and NX3 resin cements. Ten specimens (1 × 2 mm2) of each resin cement were photo-polymerized and then subjected to color stability assessments. In addition, 30 samples of each of the four resin cements were prepared and then immersed in three staining solutions (tea, coffee, and distilled water) for two weeks. Changes in color for the immersed versus non-immersed specimens (control specimens) were determined by comparing ΔL (lightness), Δa, and Δb (color components), and an overall ΔE (color difference) obtained from spectrophotometry assays. One-way analysis of variance and a multiple comparison test (Tukey’s test) were used to analyze color stability and DC data. NX3 and Variolink Esthetic resin cements exhibited significantly lower values compared to the dual cured resin cements (Variolink-N and Calibra). Results: The highest DC values were observed among the photo-polymerized samples of Variolink Esthetic (87.18 ± 2.90%), while the lowest DC values were observed among the Variolink-N samples (44.55 ± 4.33%). Conclusion: The resin cement, Variolink Esthetic, containing a novel dibenzoyl germanium derivative photo-initiator exhibited superior color stability ( p < 0.05) and a higher DC than other resin cements containing conventional luting agents in an in vitro setting.

scholarly journals Correlation between the degree of conversion and the elution of leachable components from dental resin-based cements

2011 ◽  
Vol 76 (9) ◽  
pp. 1307-1323 ◽  
Author(s):  
Kosovka Obradovic-Djuricic ◽  
Vesna Medic ◽  
Marina Radisic ◽  
Mila Lausevic
Keyword(s):  
Triethylene Glycol ◽  
Degree Of Conversion ◽  
Cement Matrix ◽  
Dental Resin ◽  
Resin Cements ◽  
Triethylene Glycol Dimethacrylate ◽  
Urethane Dimethacrylate ◽  
Post Hoc ◽  
Composite Cements ◽  
One Way Anova

This study examined the possible correlation between the degree of conversion (DC) and the amount of substances eluted from three commercial cured resin-based cements. The DC of the various resin-based cements was measured by Raman spectroscopy, while the quantity of unreacted monomers released from the cement matrix (triethylene glycol dimethacrylate, TEGDMA, urethane dimethacrylate, UDMA, 2- hydroxyethyl methacrylate, HEMA and bis phenol A) was determined by high pressure liquid chromatography (HPLC). The obtained results, after multiple statistical evaluation (one way ANOVA, LSD post hoc test), showed no significant differences in the DC values between the resin cements. On the contrary, the results of the HPLC analysis depicted statistically significant differences between the three materials with respect to the amount of leached monomers. In addition, no correlation between the DC and the amount of eluted substances from the tested cured composite cements was found.

Sign in / Sign up

Export Citation Format

Share Document