Pre-heating of dual-polymerized resin core foundation system: effect on micro-shear bond strength, degree of conversion and ultimate tensile strength

Clinical Relevance Shortened light curing does not affect volumetric polymerization shrinkage or cohesive tensile strength but negatively affects the shear bond strength of some bulk-fill resin composites. When performing shortened light curing, clinicians should be aware of the light output of their light-curing units. SUMMARY Purpose: To evaluate volumetric polymerization shrinkage (VPS), shear bond strength (SBS) to dentin, and cohesive tensile strength (CTS) of bulk-fill resin composites (BFRCs) light activated by different modes. Methods and Materials: Six groups were evaluated: Tetric EvoCeram bulk fill + high mode (10 seconds; TEC H10), Tetric EvoFlow bulk fill + high mode (TEF H10), experimental bulk fill + high mode (TEE H10), Tetric EvoCeram bulk fill + turbo mode (five seconds; TEC T5), Tetric EvoFlow bulk fill + turbo mode (TEF T5), and experimental bulk fill + turbo mode (TEE T5). Bluephase Style 20i and Adhese Universal Vivapen were used for all groups. All BFRC samples were built up on human molar bur-prepared occlusal cavities. VPS% and location were evaluated through micro–computed tomography. SBS and CTS tests were performed 24 hours after storage or after 5000 thermal cycles; fracture mode was analyzed for SBS. Results: Both TEC H10 and TEE H10 presented lower VPS% than TEF H10. However, no significant differences were observed with the turbo-curing mode. No differences were observed for the same BFRC within curing modes. Occlusal shrinkage was mostly observed. Regarding SBS, thermal cycling (TC) affected all groups. Without TC, all groups showed higher SBS values for high mode than turbo mode, while with TC, only TEC showed decreased SBS from high mode to turbo modes; modes of fracture were predominantly adhesive. For CTS, TC affected all groups except TEE H10. In general, no differences were observed between groups when comparing the curing modes. Conclusions: Increased light output with a shortened curing time did not jeopardize the VPS and SBS properties of the BFRCs, although a decreased SBS was observed in some groups. TEE generally showed similar or improved values for the tested properties in a shortened light-curing time. The VPS was mostly affected by the materials tested, whereas the SBS was affected by the materials, curing modes, and TC. The CTS was not affected by the curing modes.

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Assessment of the mechanical properties of glass ionomer cements for orthodontic cementation

Dental Press Journal of Orthodontics ◽

10.1590/s2176-94512012000600027 ◽

2012 ◽

Vol 17 (6) ◽

pp. 154-159 ◽

Cited By ~ 1

Author(s):

Marcel M. Farret ◽

Eduardo Martinelli de Lima ◽

Eduardo Gonçalves Mota ◽

Hugo Mitsuo S. Oshima ◽

Gabriela Maguilnik ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Bond Strength ◽

Shear Bond Strength ◽

Glass Ionomer Cements ◽

Glass Ionomer ◽

Resin Modified Glass Ionomer ◽

Strength Tests ◽

Diametral Tensile Strength

OBJECTIVE: To evaluate the mechanical properties of three glass ionomers cements (GICs) used for band cementation in Orthodontics. METHODS: Two conventional glass ionomers (Ketac Cem Easy mix/3M-ESPE and Meron/Voco) and one resin modified glass ionomer (Multi-cure Glass ionomer/3M-Unitek) were selected. For the compressive strength and diametral tensile strength tests, 12 specimens were made of each material. For the microhardness test 15 specimens were made of each material and for the shear bond strength tests 45 bovine permanent incisors were used mounted in a self-cure acrylic resin. Then, band segments with a welded bracket were cemented on the buccal surface of the crowns. For the mechanical tests of compressive and diametral tensile strength and shear bond strength a universal testing machine was used with a crosshead speed of 1,0 mm/min and for the Vickers microhardness analysis tests a Microdurometer was used with 200 g of load during 15 seconds. The results were submitted to statistical analysis through ANOVA complemented by Tukey's test at a significance level of 5%. RESULTS: The results shown that the Multi-Cure Glass Ionomer presented higher diametral tensile strength (p < 0.01) and compressive strength greater than conventional GICs (p = 0.08). Moreover, Ketac Cem showed significant less microhardness (p < 0.01). CONCLUSION: The resin-modified glass ionomer cement showed high mechanical properties, compared to the conventional glass ionomer cements, which had few differences between them.

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Effect of anaerobic cure of self-etch adhesive on degree of conversion and shear bond strength

Clinical Oral Investigations ◽

10.1007/s00784-018-2645-1 ◽

2018 ◽

Vol 23 (5) ◽

pp. 2227-2233

Author(s):

Melissa Phaneuf ◽

Asmaa Haimeur ◽

Rodrigo França

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Degree Of Conversion ◽

Self Etch

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Bond strength and ultimate tensile strength of resin composite filled into dentine cavity; effect of bulk and incremental filling technique

Journal of Dentistry ◽

10.1016/j.jdent.2007.12.006 ◽

2008 ◽

Vol 36 (3) ◽

pp. 228-234 ◽

Cited By ~ 19

Author(s):

Ma’an M. Nayif ◽

Masatoshi Nakajima ◽

Richard M. Foxton ◽

Junji Tagami

Keyword(s):

Tensile Strength ◽

Ultimate Tensile Strength ◽

Bond Strength ◽

Resin Composite ◽

Cavity Effect

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Empirical models for estimating properties of developed composite material from agro waste

Material Science Research India ◽

10.13005/msri/070204 ◽

2010 ◽

Vol 7 (2) ◽

pp. 347-354

Author(s):

J. O. Osarenmwinda ◽

J. C Nwachukwu

Keyword(s):

Tensile Strength ◽

Composite Material ◽

Ultimate Tensile Strength ◽

Yield Strength ◽

Bond Strength ◽

Modulus Of Elasticity ◽

Internal Bond ◽

Empirical Models ◽

Modulus Of Rupture ◽

Thickness Swelling

Study was carried out to develop an empirical models for estimating the properties of developed composite material from agro waste (sawdust and palm kernel shell). The properties of the produced composite materials from agro waste obtained in previous experimental investigation were used to determine empirical model for hardness, yield strength, ultimate tensile strength, modulus of elasticity; modulus of rupture, internal bond strength, density, thickness swelling and water absorption .The values obtained from the empirical models were found to compare favourably with the experimental values. The mean percentage error were determined to be -0.02167% (hardness), -0.462167%( yield strength),-0.03625 (ultimate tensile strength), -0.01045% (modulus of elasticity), -0.044057% (modulus of rupture), 0.001033% (internal bond strength),0.2153%(density), 0.5277% (thickness swelling) and 0.1365% (water absorption). These values were insignificant and below the maximum recommended error of 10%. These model performance were therefore found to be satisfactory and show good predictability.

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Antimicrobial properties, mechanics, and fluoride release of ionomeric cements modified by red propolis

The Angle Orthodontist ◽

10.2319/083120-759.1 ◽

2021 ◽

Author(s):

Gêisa Aiane de Morais Sampaio ◽

Rogério Lacerda-Santos ◽

Yuri Wanderley Cavalcanti ◽

Gustavo Henrique Apolinário Vieira ◽

Cassiano Francisco Weege Nonaka ◽

...

Keyword(s):

Mechanical Properties ◽

Antimicrobial Activity ◽

Tensile Strength ◽

Compressive Strength ◽

Bond Strength ◽

Shear Bond Strength ◽

Fluoride Release ◽

Tukey Test ◽

Release Capacity ◽

Diametral Tensile Strength

ABSTRACT Objectives To evaluate the antimicrobial activity, mechanical properties, and fluoride release capacity of glass ionomer cement (GIC) used for cementing orthodontic bands and modified by ethanolic extract of red propolis (EERP) in different concentrations. Materials and Methods Two orthodontic GICs containing EERP at 10%, 25%, and 50%, were used. The following assays were carried out: cell viability tests against Streptococcus mutans and Candida albicans, diametral tensile strength, compressive strength, shear bond strength, microhardness, and fluoride release capacity. The statistical analyses of the antimicrobial tests, fluoride release, diametral tensile strength, compressive strength, and microhardness were performed using two-way analysis of variance and Tukey test (P < .05). Shear bond strength data were analyzed using one-way analysis of variance followed by Tukey test (P < .05). Results At the concentrations of 25% and 50%, EERP was shown to be a promising antimicrobial agent incorporated into GICs against C albicans (P < .001) and S mutans (P < .001). The fluoride release capacity of the GICs was not affected, and the EERP concentration of 25% was the one that least affected the mechanical properties of the cements (P > .05). Conclusions The GICs containing EERP at 25% showed a significant increase in their antimicrobial activity against S mutans and C albicans, while mechanical properties and fluoride release remained without significant changes.

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Effect of Incorporation of Hydroxyapatite Nanorods on the Rheological Properties, Micro-shear Bond Strength and Degree of Conversion of Two Dental Adhesives

Al-Azhar Dental Journal for Girls ◽

10.21608/adjg.2017.5260 ◽

2017 ◽

Vol 4 (3) ◽

pp. 205-213

Author(s):

Nesreen Mohammed ◽

Inas Motawea ◽

Heba Eltayeb

Keyword(s):

Bond Strength ◽

Rheological Properties ◽

Shear Bond Strength ◽

Degree Of Conversion ◽

Dental Adhesives

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Flexural Strength of Resin Core Build-Up Materials: Correlation to Root Dentin Shear Bond Strength and Pull-Out Force

Polymers ◽

10.3390/polym12122947 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2947

Author(s):

Masao Irie ◽

Yukinori Maruo ◽

Goro Nishigawa ◽

Kumiko Yoshihara ◽

Takuya Matsumoto

Keyword(s):

Flexural Strength ◽

Bond Strength ◽

Shear Bond Strength ◽

Water Storage ◽

Bending Test ◽

Pull Out ◽

Resin Core ◽

Root Dentin ◽

Bond Strengths ◽

Almost All

The aims of this study were to investigate the effects of root dentin shear bond strength and pull-out force of resin core build-up materials on flexural strength immediately after setting, after one-day water storage, and after 20,000 thermocycles. Eight core build-up and three luting materials were investigated, using 10 specimens (n = 10) per subgroup. At three time periods—immediately after setting, after one-day water storage, and after 20,000 thermocycles, shear bond strengths to root dentin and pull-out forces were measured. Flexural strengths were measured using a 3-point bending test. For all core build-up and luting materials, the mean data of flexural strength, shear bond strength and pull-out force were the lowest immediately after setting. After one-day storage, almost all the materials yielded their highest results. A weak, but statistically significant, correlation was found between flexural strength and shear bond strength (r = 0.508, p = 0.0026, n = 33). As the pull-out force increased, the flexural strength of core build-up materials also increased (r = 0.398, p = 0.0218, n = 33). Multiple linear regression analyses were conducted using these three independent factors of flexural strength, pull-out force and root dentin shear bond strength, which showed this relationship: Flexural strength = 3.264 × Shear bond strength + 1.533 × Pull out force + 10.870, p = 0.002). For all the 11 core build-up and luting materials investigated immediately after setting, after one-day storage and after 20,000 thermocycles, their shear bond strengths to root dentin and pull-out forces were correlated to the flexural strength in core build-up materials. It was concluded that the flexural strength results of the core build-up material be used in research and quality control for the predictor of the shear bond strength to the root dentin and the retentive force of the post.

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