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Al-Akhali M, Kern M, Elsayed A, Samran A, Chaar MS. Influence of thermomechanical fatigue on the fracture strength of CAD-CAM-fabricated occlusal veneers. J Prosthet Dent 2019; 121:644-650. [DOI: 10.1016/j.prosdent.2018.07.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 07/22/2018] [Accepted: 07/23/2018] [Indexed: 11/16/2022]
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Effect of a self-etching primer containing 4-META and sodium sulfite after phosphoric acid etching on bonding strength of MMA-TBB resin to human enamel. J Prosthodont Res 2018; 63:145-149. [PMID: 30528398 DOI: 10.1016/j.jpor.2018.10.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 10/24/2018] [Accepted: 10/30/2018] [Indexed: 11/21/2022]
Abstract
PURPOSE The aim of this study was to evaluate the shear bond strength and durability of MMA-TBB resin to human enamel applied a self-etching primer with phosphoric acid etching. METHODS A self-etching primer (Teeth primer, TP) containing 4-methacryloyloxyethyl trimellitate anhydride (4-META) and sodium sulfite and two etchants having different phosphoric acid concentrations (K-etchant gel, KE, 35-45%: Red gel, RG, 20-25%) were used as treatment agent, and MMA-TBB resin was used as luting agent. Enamel surfaces were treated with six methods which were as follow: KE, RG, TP, KE+TP, and RG+TP. After enamel specimens were bonded with MMA-TBB resin and stored in distilled water for 24h, the shear bond strength test was done at 0 thermocycling or 20,000 thermocycling. These results were statistically verified with Steel-Dwass multiple comparisons and Man-Whitney U test. RESULTS The shear bond strength of TP group, KE+TP group, and RG+TP group were significantly higher than KE group and RG group in pre-thermocycling. KE+TP group and RG+TP group were significantly higher than other groups in post-thermocycling. CONCLUSIONS Applying TP with phosphoric acid etching can increased shear bond durability despite difference of phosphoric acid concentrations (35-45% or 20-25%).
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Al-Akhali M, Chaar MS, Elsayed A, Samran A, Kern M. Fracture resistance of ceramic and polymer-based occlusal veneer restorations. J Mech Behav Biomed Mater 2017. [DOI: 10.1016/j.jmbbm.2017.06.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Influence of various bonding techniques on the fracture strength of thin CAD/CAM-fabricated occlusal glass-ceramic veneers. J Mech Behav Biomed Mater 2017; 75:504-511. [PMID: 28843882 DOI: 10.1016/j.jmbbm.2017.08.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 08/06/2017] [Accepted: 08/10/2017] [Indexed: 11/21/2022]
Abstract
OBJECTIVES To evaluate the efficiency of immediate dentin sealing and the effects of different bonding protocols on the fracture strength of CAD/CAM occlusal veneers bonded to exposed dentin. METHODS Ninety-six extracted maxillary premolars were initially divided into three main groups with 32 specimens each: without immediate dentin sealing, immediate dentin sealing/total etching and immediate dentin sealing/selective etching. Teeth were identically prepared in the dentin to receive occlusal veneers of 0.8mm thickness, milled from lithium disilicate ceramic blocks (IPS e.max CAD). Each main group was later subdivided, according to the pre-cementation surface etching protocol (total/selective), into two subgroups with 16 specimens each. All restorations were adhesively bonded using a resin cement (Variolink Esthetic). Half of the specimens of each subgroup were subjected to thermo-dynamic loading in a chewing simulator with 1,200,000 cycles at 10kg load. The other half and the surviving specimens were subjected to quasi-static loading until failure. Statistical analysis was performed using three-way ANOVA and Tukey's post-hoc tests. RESULTS All specimens except one survived the artificial aging. A significantly higher fracture strength of restorations (p ≤ 0.001) was obtained when immediate dentin sealing was followed regardless of the etching method with values ranging from a minimum of 1122 ± 336N to a maximum of 1853 ± 333N. Neither the pre-cementation treatment nor the artificial aging had a statistical significant effect on the fracture strength. SIGNIFICANCE Immediate dentin sealing protocol is recommended whenever dentin is exposed during the preparation for thin glass-ceramic occlusal veneers.
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Does acid etching morphologically and chemically affect lithium disilicate glass ceramic surfaces? J Appl Biomater Funct Mater 2017; 15:e93-e100. [PMID: 27647389 DOI: 10.5301/jabfm.5000303] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/04/2016] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND This study evaluated the surface morphology, chemical composition and adhesiveness of lithium disilicate glass ceramic after acid etching with hydrofluoric acid or phosphoric acid. METHODS Lithium disilicate glass ceramic specimens polished by 600-grit silicon carbide paper were subjected to one or a combination of these surface treatments: airborne particle abrasion with 50-μm alumina (AA), etching with 5% hydrofluoric acid (HF) or 36% phosphoric acid (Phos), and application of silane coupling agent (Si). Stainless steel rods of 3.6-mm diameter and 2.0-mm height were cemented onto treated ceramic surfaces with a self-adhesive resin cement (Clearfil SA Cement). Shear bond strengths between ceramic and cement were measured after 24-hour storage in 37°C distilled water. RESULTS SEM images of AA revealed the formation of conventional microretentive grooves, but acid etching with HF or Phos produced a porous surface. Bond strengths of AA+HF+Si (28.1 ± 6.0 MPa), AA+Phos+Si (17.5 ± 4.1 MPa) and HF+Si (21.0 ± 3.0 MPa) were significantly greater than those of non-pretreated controls with Si (9.7 ± 3.7 MPa) and without Si (4.1 ± 2.4 MPa) (p<0.05). In addition, HF etching alone (26.2 ± 7.5 MPa) had significantly higher bond strength than AA alone (11.5 ± 4.0 MPa) (p<0.05). AA+HF, AA+Phos and HF showed cohesive failures. CONCLUSIONS Etching with HF or Phos yielded higher bond strength between lithium disilicate glass ceramic and self-adhesive resin cement without microcrack formation.
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Influence of frequency on shear fatigue strength of resin composite to enamel bonds using self-etch adhesives. J Mech Behav Biomed Mater 2016; 62:291-298. [DOI: 10.1016/j.jmbbm.2016.05.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 11/17/2022]
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Santana RM, Rached RN, Souza EM, Guariza-Filho O, Camargo ES, Pithon MM, Tanaka OM. Effect of organic solvents and ultrasound on the removal of orthodontic brackets. Orthod Craniofac Res 2016; 19:137-44. [PMID: 26898697 DOI: 10.1111/ocr.12121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To evaluate the effect of organic gel solvents (70% acetone and 90% ethanol) and ultrasound in the removal of metallic brackets. MATERIALS AND METHODS Metallic brackets were bonded with light-cured orthodontic composite (Transbond XT) in 120 human bicuspids and divided into 6 groups for the enamel etch-and-rinse adhesive system (XT) and 6 groups to self-etching system (SEPT) according to pretreatment to removal test: control, 70% acetone, 90% ethanol, ultrasound, 70% acetone+ultrasound, and 90% ethanol+ultrasound. The brackets were subjected to removal by shear testing and Adhesive Remnant Index (ARI) evaluation. Some specimens were prepared and its adhesive interface and etching ability observed by scanning electron microscopy (SEM). RESULTS Only the factor 'ultrasound' and its interaction with 'adhesive' were detected as a source of variance, with the SEPT/ultrasound showing the lowest shear strength than the other groups. Regardless the factor 'ultrasound', XT showed a higher ARI than SEPT; however, when the solvents were used, no differences were detected between XT and SEPT. CONCLUSION The organic solvents were not effective in reducing shear bond strength. The etch-and-rinse adhesive system showed a higher and more favorable ARI score than the self-etching primer. The behavior of the organic solvents on ARI showed to be better when associated with the self-etching primer. The ultrasound was effective in reducing the shear bond strength of the self-etching adhesive system but not in affecting the ARI of the adhesive systems.
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Affiliation(s)
- R M Santana
- Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - R N Rached
- Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - E M Souza
- Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - O Guariza-Filho
- Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - E S Camargo
- Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
| | - M M Pithon
- Southwest Bahia State University - UESB, Bahia, Brazil
| | - O M Tanaka
- Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
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Takamizawa T, Barkmeier WW, Tsujimoto A, Scheidel DD, Watanabe H, Erickson RL, Latta MA, Miyazaki M. Influence of water storage on fatigue strength of self-etch adhesives. J Dent 2015; 43:1416-27. [DOI: 10.1016/j.jdent.2015.10.018] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 10/23/2015] [Accepted: 10/25/2015] [Indexed: 11/29/2022] Open
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Nogawa H, Koizumi H, Saiki O, Hiraba H, Nakamura M, Matsumura H. Effect of a self-etching primer and phosphoric acid etching on the bond strength of 4-META/MMA-TBB resin to human enamel. Dent Mater J 2015; 34:219-26. [PMID: 25740168 DOI: 10.4012/dmj.2014-227] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The purpose of this study was to evaluate the shear bond strength and durability of 4-META/MMA-TBB resin to human enamel. A self-etching primer that contained 4-META (Teeth Primer, TP) and 35-45% or 60-65% concentrations of phosphoric acid (K-Etchant Gel, KE, and Super Bond C&B Red Activator, RA) were used as the surface treatment agents. A methyl methacrylate (MMA)-based self-polymerizing resin (Super-Bond C&B) was used as a luting agent. The shear bond strength was determined both pre and post thermocycling. The results were statistically analyzed with a non-parametric procedure. The post-thermocycling shear bond strength of the TP group was significantly higher than that of other groups, and that of the KE group was significantly higher compared with the RA group. These results demonstrated that 4-META was effective. Furthermore, when the degree of tooth demineralization was compared, surface treatment with less demineralization using TP was the most effective treatment.
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Affiliation(s)
- Hiroshi Nogawa
- Division of Applied Oral Sciences, Nihon University Graduate School of Dentistry
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Costa LA, Carneiro KK, Tanaka A, Lima DM, Bauer J. Evaluation of pH, ultimate tensile strength, and micro-shear bond strength of two self-adhesive resin cements. Braz Oral Res 2014; 28:1-7. [PMID: 25337932 DOI: 10.1590/1807-3107bor-2014.vol28.0055] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 06/24/2014] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to evaluate the pH, ultimate tensile strength (UTS), and micro-shear bond strength (µSBS) of two self-adhesive resin cements to enamel and dentin. Sound bovine incisors (n = 10) and two self-adhesive resin cements (i.e., RelyX U-100 and seT PP) were used. The pH of the resin cements was measured using a pH-indicator paper (n = 3). Specimens for UTS were obtained from an hourglass-shaped mold. For µSBS, cylinders with internal diameter of 0.75 mm and height of 0.5 mm were bonded to the flat enamel and dentin surfaces. Bonded cylinders were tested in the shear mode using a loop wire. The fracture mode was also evaluated. The cement seT PP showed a low pH; U-100 showed significantly higher UTS (49.9 ± 2.0) than seT PP (40.0 ± 2.1) (p < 0.05) and high µSBS to enamel (10.7 ± 3.7). The lowest µSBS was found for seT PP to dentin (0.7 ± 0.6); seT PP to enamel (4.8 ± 1.7), and for U-100 to dentin (7.2 ± 1.9), showing an intermediate µSBS value (p < 0.05). Adhesive failure was the most frequently observed failure mode. The resin cement that presented the lowest pH and UTS also presented the lowest micro-shear bond strength to enamel and dentin.
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Affiliation(s)
- Luciana Artioli Costa
- Department of Dentistry I, School of Dentistry, Universidade Federal do Maranhão, São Luis, MA, Brazil
| | - Karina Kato Carneiro
- Department of Dentistry I, School of Dentistry, Universidade Federal do Maranhão, São Luis, MA, Brazil
| | - Auro Tanaka
- Department of Chemistry, Center of Sciences and Technology, Universidade Federal do Maranhão, São Luis, MA, Brazil
| | - Darlon Martins Lima
- Department of Dentistry I, School of Dentistry, Universidade Federal do Maranhão, São Luis, MA, Brazil
| | - José Bauer
- Department of Dentistry I, School of Dentistry, Universidade Federal do Maranhão, São Luis, MA, Brazil
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Bastos LA, Sousa ABS, Drubi-Filho B, Panzeri Pires-de-Souza FDC, Garcia LDFR. Microtensile bond strength of silorane-based composite specific adhesive system using different bonding strategies. Restor Dent Endod 2014; 40:23-9. [PMID: 25671209 PMCID: PMC4320273 DOI: 10.5395/rde.2015.40.1.23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 08/06/2014] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVES The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. MATERIALS AND METHODS Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE), the specific self-etching adhesive system (Adhesive System P90, 3M ESPE) was used with and without pre-etching (Pre-etching/Silorane and Silorane groups). Teeth restored with methacrylate based-composite (Filtek Z250, 3M ESPE) were hybridized with the two-step self-etching system (Clearfil SE Bond, Kuraray), with and without pre-etching (Pre-etching/Methacrylate and Methacrylate groups), or three-step adhesive system (Adper Scotchbond Multi-Purpose, 3M ESPE) (Three-step/Methacrylate group) (n = 6). The restored teeth were sectioned into stick-shaped test specimens (1.0 × 1.0 mm), and coupled to a universal test machine (0.5 mm/min) to perform microtensile testing. RESULTS Pre-etching/Methacrylate group presented the highest bond strength values, with significant difference from Silorane and Three-step/Methacrylate groups (p < 0.05). However, it was not significantly different from Preetching/Silorane and Methacrylate groups. CONCLUSIONS Pre-etching increased bond strength of silorane-based composite specific adhesive system to dentin.
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Affiliation(s)
- Laura Alves Bastos
- Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Ana Beatriz Silva Sousa
- Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Brahim Drubi-Filho
- Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Lucas da Fonseca Roberti Garcia
- Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, SP, Brazil
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Hattar S, Hatamleh M, Khraisat A, Al-Rabab'ah M. Shear bond strength of self-adhesive resin cements to base metal alloy. J Prosthet Dent 2013; 111:411-5. [PMID: 24355505 DOI: 10.1016/j.prosdent.2013.06.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 06/24/2013] [Accepted: 06/25/2013] [Indexed: 10/25/2022]
Abstract
STATEMENT OF PROBLEM Many self-adhesive cements have been introduced in the past few years, with little or no data regarding their clinical performance. This study investigated the shear bond strength of some recently introduced self-adhesive resin cements. PURPOSE The purpose of this study was to evaluate the shear bond strength of self-adhesive and conventional resin-based cements to a base metal alloy. MATERIAL AND METHODS Four groups (10-12 each) that comprised 3 self-adhesive cements (SmartCem2; RelyX Unicem; seT SDI) and a conventional resin-based cement (RelyX ARC) were tested. Cylindrical cement specimens (diameter, 3 mm; height, 3 mm) were applied to nickel-free base metal alloy (Sheradent) disks with a diameter of 12 mm, and the surface was treated with airborne-particle abrasion of 50 μm aluminum oxide. The metal disks were fixed in brass molds specifically designed for the shear bond test device. Test specimens were incubated at 37°C for 24 hours and then the shear bond was tested with a Zwick Roll testing machine at a 0.8 mm/min cross-head speed. In addition, bond failures were investigated and categorized as adhesive, cohesive, or mixed. Shear bond strengths were calculated by dividing the maximum debonding force over the cross-sectional area of each specimen. One-way ANOVA and the Tukey (honestly significant difference) post hoc test were used to test statistical significant differences among the groups (α=.05). RESULTS Statistical analysis showed significant differences among different resin cements (F=14.34, P<.001). The highest mean shear bond strength was observed for SmartCem2 (14.18 MPa), and the lowest was reported for seT (3.52 MPa). The observed failure mode in all the materials was adhesive in nature, which occurred at the resin-metal interface. CONCLUSIONS The early bond strength of self-adhesive resin cements varied significantly among the tested materials. SmartCem2 showed the highest bond strength, which was 4 times the strength observed for seT SDI.
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Affiliation(s)
- Susan Hattar
- Assistant Professor and Consultant, Department of Conservative Dentistry, Faculty of Dentistry, The University of Jordan, Amman, Jordan.
| | - Muhanad Hatamleh
- Maxillofacial Prosthetist, Queen Medical Centre, Nottingham University Hospital Trust; School of Dentistry, University of Manchester, Manchester, UK; and Faculty of Applied Medical Sciences, Jordan University of Science and Technology, Jordan
| | - Ameen Khraisat
- Professor and First-Consultant, Department of Conservative Dentistry, Faculty of Dentistry, The University of Jordan, Amman, Jordan
| | - Mohammad Al-Rabab'ah
- Assistant Professor and Consultant, Department of Conservative Dentistry, Faculty of Dentistry, The University of Jordan, Amman, Jordan
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Pires PT, Ferreira JC, Oliveira SA, Azevedo AF, Dias WR, Melo PR. Shear bond strength and SEM morphology evaluation of different dental adhesives to enamel prepared with ER:YAG laser. Contemp Clin Dent 2013; 4:20-6. [PMID: 23853447 PMCID: PMC3703689 DOI: 10.4103/0976-237x.111588] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
CONTEXT Early observations of enamel surfaces prepared by erbium lasers motivated clinicians to use laser as an alternative to chemical etching. AIMS Evaluate shear bond strength (SBS) values of different dental adhesives on Erbium:Yttrium Aluminum Garnet (Er:YAG) laser prepared enamel and to evaluate possible etching patterns correlations between dental adhesives and SBS values. SUBJECTS AND METHODS One hundred bovine incisors were randomly assigned to SBS tests on enamel (n = 15) and to enamel morphology analysis (n = 5) after Er:YAG laser preparation as follows: Group I - 37% phosphoric acid (PA)+ ExciTE(®); Group II - ExciTE(®); Group III - AdheSE(®) self-etching; Group IV - FuturaBond(®) no-rinse. NR; Group V - Xeno(®) V. Teeth were treated with the adhesive systems and subjected to thermal cycling. SBS were performed in a universal testing machine at 5 mm/min. STATISTICAL ANALYSIS USED One-way ANOVA and post-hoc tests (P < 0.05). For the morphology evaluation, specimens were immersed in Ethylenediamine tetraacetic acid (EDTA) and the etching pattern analyzed under Scanning Electron Microscope (SEM). RESULTS Mean bond strengths were Group I - 47.17 ± 1.61 MPa (type I etching pattern); Group II - 32.56 ± 1.64 MPa, Group III - 29.10 ± 1.34 MPa, Group IV - 23.32 ± 1.53 MPa (type III etching pattern); Group V - 24.43 MPa ± 1.55 (type II etching pattern). CONCLUSIONS Different adhesive systems yielded significantly different SBSs. Acid etching significantly increased the adhesion in laser treated enamel. No differences in SBS values were obtained between AdheSE(®) and ExciTE(®) without condition with PA. FuturaBond(®) NR and Xeno(®) V showed similar SBS, which was lower in comparison to the others adhesives. No correlation between enamel surface morphology and SBS values was observed, except when PA was used.
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Affiliation(s)
- Patrícia T Pires
- Department of Operative Dentistry, Faculty of Dentistry, University of Porto, Porto, Portugal
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Pires PT, Ferreira JC, Oliveira SA, Silva MJ, Melo PR. Effect of ozone gas on the shear bond strength to enamel. J Appl Oral Sci 2013; 21:177-82. [PMID: 23739859 PMCID: PMC3881866 DOI: 10.1590/1678-7757201302362] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2012] [Accepted: 01/25/2013] [Indexed: 11/24/2022] Open
Abstract
Ozone is an important disinfecting agent, however its influence on enamel adhesion has not yet been clarified.
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