Effect of reduction of phosphoric acid concentration on the shear bond strength of brackets

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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Effect of phosphoric acid etching on the shear bond strength of two self-etch adhesives

Journal of Applied Oral Science ◽

10.1590/1678-7757201302370 ◽

2013 ◽

Vol 21 (1) ◽

pp. 56-62 ◽

Cited By ~ 5

Author(s):

Camila SABATINI

Keyword(s):

Phosphoric Acid ◽

Bond Strength ◽

Shear Bond Strength ◽

Acid Etching ◽

Self Etch ◽

Phosphoric Acid Etching

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Reinforcement of bond strength of self-etching orthodontic adhesive

The Angle Orthodontist ◽

10.2319/012011-39.1 ◽

2011 ◽

Vol 82 (1) ◽

pp. 30-35

Author(s):

Shinya Horiuchi ◽

Shingo Kuroda ◽

Masahiro Hiasa ◽

Toshiyuki Suge ◽

Seitaro Saku ◽

...

Keyword(s):

Citric Acid ◽

Phosphoric Acid ◽

Bond Strength ◽

Polyacrylic Acid ◽

Shear Bond Strength ◽

Adhesive System ◽

Control Group ◽

Bonding System ◽

Adhesive Remnant Index ◽

Debonding Process

Abstract Objective: To determine the reinforcement of bond strength of a self-etching system by applying a pretreatment agent. Materials and Methods: Sixty extracted human premolars were used in this study. The enamel surfaces were treated with four pretreatment agents—phosphoric acid, polyacrylic acid, citric acid, and ammonium hexafluorosilicate (SiF)—and were examined under a scanning electron microscope. Afterward, orthodontic brackets were bonded with a self-etching adhesive system (n = 10 for each agent), and shear bond strength was measured through a debonding process. The adhesive remnant index (ARI) was also assessed. Results: Enamel surfaces treated with polyacrylic acid seemed almost the same as intact enamel. Treatment with SiF induced slight shallow depressions compared with the intact enamel. On the other hand, enamel surfaces treated with citric acid and phosphoric acid showed severe etching patterns. All pretreatments increased the bond strength, but SiF-treated specimens revealed the greatest strength (12.201 ± 1.048 MPa), followed by polyacrylic acid (12.030 ± 2.103 MPa). The control group with no pretreatment showed the least strength (9.078 ± 1.678 MPa). All pretreatments increased ARI score compared with the control group. Conclusions: Surface conditioning before bracket adhesion could reinforce the bond strength of the self-etching adhesive system, resulting in a more reliable bonding system.

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Impact of Intracoronal Dentin Treatment Prior to Bleaching on Bond Strength of Restorative Materials

Brazilian Dental Journal ◽

10.1590/0103-6440201302441 ◽

2014 ◽

Vol 25 (6) ◽

pp. 519-523 ◽

Cited By ~ 2

Author(s):

Erica Moreno Zanconato-Carvalho ◽

João Felipe Bruniera ◽

Natália Spadini de Faria ◽

Vivian Colucci ◽

Danielle Cristine Messias

Keyword(s):

Phosphoric Acid ◽

Bond Strength ◽

Surface Treatment ◽

Shear Bond Strength ◽

Composite Resin ◽

Er:Yag Laser ◽

Composite Resins ◽

Bleaching Procedure ◽

Significant Difference ◽

Restorative Materials

Surface treatment of dentin before the bleaching procedure may affect its permeability and influence the bond strength of restorative materials. This study evaluated the influence of surface treatment before the bleaching on shear bond strength (SBT) of restorative materials to intracoronal dentin. Dentin slabs were subjected to surface treatment: no bleaching (control - CON), no surface treatment + bleaching (HP), 37% phosphoric acid + bleaching (PA) and Er:YAG laser + bleaching (L). After the bleaching procedure, specimens (n=10) were restored with: microhybrid composite resin (MH), flowable composite resin (F), and resin-modified glass-ionomer cement (RMGIC). The shear test was carried out. ANOVA and Tukey's test (α=0.05) showed significant difference for surface treatment and restorative materials (p<0.05). CON presented higher STB and was statistically different from HP (p<0.05). PA and L showed intermediate values and were statistically similar to CON and HP (p>0.05). STB for MH and F were higher than RMGIC (p<0.05), and did not differ from each other (p>0.05). The surface treatments with phosphoric acid and Er:YAG laser before the bleaching procedure provided shear bond strength at the same level of unbleached dentin and the composite resins presented superior bond strength to the intracoronal dentin.

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Modeling and comparative study of heat exchangers fouling in phosphoric acid concentration plant using experimental data

Heat and Mass Transfer ◽

10.1007/s00231-020-02888-9 ◽

2020 ◽

Vol 56 (9) ◽

pp. 2653-2666

Author(s):

Rania Jradi ◽

Christophe Marvillet ◽

Mohamed Razak Jeday

Keyword(s):

Experimental Data ◽

Phosphoric Acid ◽

Comparative Study ◽

Acid Concentration ◽

Heat Exchangers ◽

Concentration Plant ◽

Phosphoric Acid Concentration

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Multiple Regression Corrosion Models and Corrosion Mechanism of High Chromium Cast Iron under Phosphoric Acid Medium Condition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.941-944.1367 ◽

2014 ◽

Vol 941-944 ◽

pp. 1367-1371

Author(s):

Liu Jie Xu ◽

Bao Yuan Li ◽

An Heng Si ◽

Shi Zhong Wei

Keyword(s):

Weight Loss ◽

Cast Iron ◽

Phosphoric Acid ◽

Acid Medium ◽

Acid Concentration ◽

Corrosion Property ◽

High Chromium ◽

High Chromium Cast Iron ◽

Chromium Cast Iron ◽

Phosphoric Acid Concentration

The corrosion property of high chromium cast iron was test under different phosphoric acid medium concentration. On the base of experimental data, the binary equation model of corrosion weight loss (W) versus phosphoric acid concentration and corrosion time (c, t) was built using multiple regression analysis, which can predict corrosion property of high chromium cast iron effectively. The prediction results show that the corrosion weight loss rises lineally with increasing corrosion time, and the corrosion rate rises quadratically with increasing phosphoric acid concentration. The corrosion failure mechanism is that chromium composite carbides (M7C3) stand out of matrixes surface after the matrixes composed of martensite and austenite are corroded firstly, then the M7C3 carbides drop out of matrixes when the matrixes can not wrap M7C3 carbides, resulting gradual corrosion of high chromium cast iron. The prediction values have sufficiently mined the basic domain knowledge of corrosion process of high chromium cast iron under phosphoric acid medium. Therefore, a new way of predicting corrosion property according to corrosion conditions was provided by the authors.

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Evaluation of Shear Bond Strength and SEM Observation of All-in-one Self-etching Primer Used for Bonding of Fissure Sealants

The Journal of Contemporary Dental Practice ◽

10.5005/jcdp-7-2-9 ◽

2006 ◽

Vol 7 (2) ◽

pp. 9-16 ◽

Cited By ~ 13

Author(s):

Maha Abdulla Al-Sarheed

Keyword(s):

Phosphoric Acid ◽

Bond Strength ◽

Shear Bond Strength ◽

Testing Machine ◽

Fissure Sealants ◽

Fissure Sealant ◽

Sem Observation ◽

Instron Testing Machine ◽

Acid Etch ◽

The Mean

Abstract Objectives To evaluate and compare enamel shear bond strength of an all-in-one self-etching primer (Prompt™ L-Pop™) to regular acid etch material when bonded to two-fissure sealant systems (Concise and Dyract Seal). Method and Materials Forty newly extracted non-carious first permanent molars were embedded in a Teflon mold. The teeth were divided into four groups and each consisted of ten specimens. The bonding surfaces were treated with either Prompt L-Pop as recommended by the manufacturer or etched with phosphoric acid. After 24 hours of water storage, the specimens were evaluated for shear bond strength using an Instron testing machine. Scanning electron microscope (SEM) examinations were carried out to evaluate the failure sites of the sealants. Results The mean shear bond strengths using Prompt L-Pop were Concise: 23.46 MPa and Dyract Seal: 20.34 MPa. These values were higher than and statistically different from those of Dyract Seal (9.99 MPa) and Concise (8.85 MPa) when phosphoric acid was used. The failure was predominantly of the adhesive type. The SEM examination showed the failure of debonding was predominantly related to the type of etching systems used rather than the type of fissure sealants. Conclusion The use of the all-in-one self-etching adhesive Prompt L-Pop improves the mean enamel shear bond strength of fissure sealants. Citation Al-Sarheed MA. Evaluation of Shear Bond Strength and SEM Observation of All-in-one Self-etching Primer Used for Bonding of Fissure Sealants. J Contemp Dent Pract 2006 May;(7)2:009-016.

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