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Ramos RQ, Peumans M, Mercelis B, Ahmed MH, Politano G, Lopes GC, Van Meerbeek B. Influence of airborne particle abrasion on dentin bonding effectiveness of a 2-step universal adhesive. J Dent 2024; 144:104918. [PMID: 38461887 DOI: 10.1016/j.jdent.2024.104918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 03/12/2024] Open
Abstract
OBJECTIVE To determine the effect of airborne particle abrasion (APA) on micro-tensile bond strength (µTBS) to dentin using different air-abrasion/polishing powders. METHODS The bonding effectiveness of G2 Bond Universal (G2B), used in etch-and-rinse (E&R) and self-etch mode (SE), was tested on bur-cut dentin and dentin air abraded/polished using six different powders (aluminum oxide 29 µm (AO29) and 53 µm (AO53), aluminum trihydroxide (AT), sodium bicarbonate (SB), sodium bicarbonate soft (SBsoft) and bioactive glass (BG); Velopex). Adhesive-composite resin specimens were immersed in distilled water at 37 °C for one week and cut into microspecimens. Half of the specimens were subjected to 50,000 thermocycles (aged). Immediate and aged μTBS to dentin were measured. Statistical analysis was performed using linear mixed-effects (LME) modeling (p < 0.05). RESULTS Comparing the aged bond strengths to air-abraded/polished dentin with bur-cut dentin, pretreatment with SB and SBsoft in combination with G2B used in E&R mode, and BG air polishing in combination with both application modes (E&R, SE), resulted in a significantly higher bond strength. Dentin bond strength was only significantly lower when air abraded with AO29 and using G2B in SE mode. Aging did not significantly influence bond strength for both application modes (E&R, SE), except for AO29 and AT-treated dentin, where bond strengths decrea sed significantly using G2B in SE mode. In general, G2B reached significantly higher bond strengths on air-abraded/polished dentin in E&R mode than in SE mode. CONCLUSION Air-abrasion/polishing did not impair dentin bond strength using G2B, except when dentin was air abraded with AO29 and using G2B in SE mode. Air polishing positively influenced the bond strength to dentin in specific groups. CLINICAL SIGNIFICANCE APA is safe concerning bonding to dentin. The E&R application mode is preferred using G2B as adhesive on air-abraded/polished dentin. Air polishing with BG positively influenced dentin bond strength for both application methods.
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Affiliation(s)
- R Q Ramos
- Joint Ph.D. student at KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7, 3000 Leuven, Belgium and at UFSC (Universidade Federal de Santa Catarina), SC, Brazil
| | - M Peumans
- Associate Professor, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7, 3000 Leuven, Belgium.
| | - B Mercelis
- Lab Coordinator, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7, 3000 Leuven, Belgium
| | - M H Ahmed
- Post-doctoral Research Fellow KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7, 3000 Leuven, Belgium
| | - G Politano
- Dentist in Private Practice, Viale dell'Umanesimo, 199, Largo Maresciallo Diaz, 13 00100, Rome, Italy
| | - G C Lopes
- Associate Professor, UFSC (Universidade Federal de Santa Catarina), Department of Dentistry, Rua Delfino Conti, 1240, Campus Trindade, Florianópolis, Santa Catarina, Brazil
| | - B Van Meerbeek
- Full Professor, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7, 3000 Leuven, Belgium
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Tang C, Mercelis B, Zhang F, Mocquot C, Nakanishi K, Yoshihara K, Peumans M, Van Meerbeek B. Filler Mixed Into Adhesives Does Not Necessarily Improve Their Mechanical Properties. Oper Dent 2024:500011. [PMID: 38632849 DOI: 10.2341/23-106-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2023] [Indexed: 04/19/2024]
Abstract
OBJECTIVES To investigate the influence of filler type/loading on the micro-tensile fracture strength (μTFS) of adhesive resins, as measured 'immediately' upon preparation and after 1-week water storage ('water-stored'). METHODS The morphology and particle-size distribution of three filler particles, referred to as 'Glass-S' (Esschem Europe), 'BioUnion' (GC), and 'CPC_Mont', were correlatively characterized by SEM, TEM, and particle-size analysis. These filler particles were incorporated into an unfilled adhesive resin ('BZF-29unfilled', GC) in different concentrations to measure the 'immediate' μTFS. After 1-week water storage, the 'water-stored' μTFS of the experimental particle-filled adhesive resins with the most optimum filler loading, specific for each filler type, was measured. In addition, the immediate and water-stored μTFS of the adhesive resins of three experimental two-step universal adhesives based on the same resin matrix but varying for filler type/loading, coded as 'BZF-21' (containing silica and bioglass), 'BZF-29' (containing solely silica), and 'BZF-29_hv' (highly viscous with a higher silica loading than BZF-29), and of the adhesive resins of the gold-standard adhesives OptiBond FL ('Opti-FL', Kerr) and Clearfil SE Bond 2 ('C-SE2', Kuraray Noritake) was measured along with that of BZF-29unfilled (GC) serving as control/reference. Statistics involved one-way and two-way ANOVA followed by post-hoc multiple comparisons (α<0.05). RESULTS Glass-S, BioUnion, and CPC_Mont represent irregular fillers with an average particle size of 8.5-9.9 μm. Adding filler to BZF-29unfilled decreased μTFS regardless of filler type/loading. One-week water storage reduced μTFS of all adhesive resins except BZF-21, with the largest reduction in μTFS recorded for BZF-29unfilled. Among the three filler types, the μTFS of the 30 wt% Glass-S and 20 wt% BioUnion filled adhesive resin was not significantly different from the μTFS of BZF-29unfilled upon water storage. CONCLUSIONS Adding filler particles into adhesive resin did not enhance its micro-tensile fracture strength but appeared to render it less sensitive to water storage as compared to the unfilled adhesive resin investigated.
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Affiliation(s)
- C Tang
- Chuliang Tang, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT, Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - B Mercelis
- Ben Mercelis, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT, Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - F Zhang
- Fei Zhang, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT, Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; KU Leuven (University of Leuven), Department of Materials Engineering, Leuven, Belgium; 3Université Lyon 1, Laboratoire des Multimatériaux et Interfaces, Villeurbanne, France
| | - C Mocquot
- Caroline Mocquot, Université Lyon 1, Laboratoire des Multimatériaux et Interfaces, Villeurbanne, France; Université Paris Cité, Faculté dentaire, Hôpital Rothschild, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - K Nakanishi
- Ko Nakanishi, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT, Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; Hokkaido University, Faculty of Dental Medicine, Department of Biomaterials and Bioengineering, Sapporo, Japan
| | - K Yoshihara
- Kumiko Yoshihara, National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute, Kagawa, Japan; Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - M Peumans
- Marleen Peumans, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT, Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - B Van Meerbeek
- *Bart Van Meerbeek, KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT, Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
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Tang C, Ahmed MH, Yao C, Mercelis B, Yoshihara K, Peumans M, Van Meerbeek B. Bonding performance of experimental HEMA-free two-step universal adhesives to low C-factor flat dentin. Dent Mater 2023:S0109-5641(23)00106-9. [PMID: 37164892 DOI: 10.1016/j.dental.2023.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 04/27/2023] [Indexed: 05/12/2023]
Abstract
OBJECTIVES Experimental two-step universal adhesives (2-UAs) providing a particle-filled hydrophobic adhesive resin with a significant film thickness to hydrophobically seal the adhesive interface were designed and synthesized. This study aimed to characterize their interfacial interaction with dentin, to determine whether the 2-UA formulations achieve durable bonding to low C-factor flat dentin and to measure their water sorption. METHODS Bonding effectiveness of 2-UAs that combine a 10-MDP-based primer with hydrophobic adhesive resins differing only for filler (BZF-21, BZF-29, and BZF-29_hv) were comparatively investigated with the commercial adhesive Clearfil SE Bond 2 (C-SE2, Kuraray Noritake). Adhesive-dentin interfaces were characterized with TEM. Adhesive-resin disks were immersed in distilled water at 37 °C for 1 week, 6 months and 1 year to measure water sorption and solubility. 'Immediate' and 'aged' micro-tensile bond strength (μTBS) of the adhesives applied in etch-and-rinse (E&R) and self-etch (SE) bonding mode to low C-factor flat dentin were measured. Statistical analyses involved linear mixed-effects (LME) modelling and Kruskal-Wallis testing (p < 0.05). RESULTS TEM revealed that E&R hybrid layers were more sensitive to aging than SE hybrid layers. Lower water sorption was recorded for all UAs compared with C-SE2. The immediate μTBS of BZF-21 and BZF-29 was not significantly different from that of C-SE2. The 1-year aged μTBS of all 2-UAs was significantly lower than that of C-SE2, except for BZF-29 applied in E&R mode. A significant reduction in μTBS upon 1-year aging was recorded for BZF-21 and BZF-29 applied in E&R mode. A significant difference in μTBS between E&R and SE bonding modes was recorded for all adhesives except BZF-21. SIGNIFICANCE Experimental 2-UAs with a hydrophobic adhesive-resin design produced± 20-μm thick adhesive-resin layers, absorbed less water and resulted in bonding performance that was more aging-resistant when applied in SE than in E&R bonding mode. The silica-filled BZF-29 2-UA revealed the most comparable bonding performance with C-SE2 in a low C-factor condition (flat dentin).
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Affiliation(s)
- C Tang
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - M H Ahmed
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; Tanta University, Faculty of Dentistry, Department of Dental Biomaterials, Tanta, Egypt
| | - C Yao
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; Wuhan University, School & Hospital of Stomatology, The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, Wuhan, China
| | - B Mercelis
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - K Yoshihara
- National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute, Kagawa, Japan; Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - M Peumans
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - B Van Meerbeek
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium.
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Ahmed MH, Yoshihara K, Nagaoka N, Yao C, Matsukawa A, Yoshida Y, Van Meerbeek B. Acrylamide monomers in universal adhesives. Dent Mater 2023; 39:246-259. [PMID: 36710097 DOI: 10.1016/j.dental.2023.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 12/28/2022] [Accepted: 01/10/2023] [Indexed: 01/29/2023]
Abstract
OBJECTIVES The mono-functional monomer 2-hydroxyethyl methacrylate (HEMA) is often added to universal adhesives (UAs) to improve surface wetting and prevent phase separation. Nevertheless, HEMA promotes water sorption and hydrolysis at adhesive interfaces, hereby affecting long-term bonding to dentin. This study investigated if two acrylamide monomers could replace HEMA in an UA formulation applied in etch-and-rinse (2E&R) and self-etch (1SE) bonding mode. METHODS Four experimental UAs were bonded to bur-cut dentin. In addition to 12 wt% 10-MDP, 25 wt% Bis-GMA and 10 wt% TEGDMA as common monomer composition, 20 %wt ethanol and 15 %wt water as solvent, and 3 wt% polymerization-related additives, the four formulations solely differed for either the acrylamide cross-linker monomer 'FAM-201' as TEGDMA alternative and HEMA replacement, the hydroxyethyl acrylamide monomer 'HEAA' as HEMA alternative, HEMA ('HEMA+'), or extra TEGDMA in a HEMA-free control ('HEMA-'), all added in a 15 wt% concentration. The split-tooth study design involved application in 2E&R mode on one tooth half versus 1SE mode on the corresponding half. Micro-tensile bond strength of half of the micro-specimens was measured upon 1-week distilled water storage ('immediate' 1w μTBS), with the other half measured after additional 6-month storage ('aged' 6 m μTBS). Statistics involved linear mixed-effects (LME) modelling (p < .05). Additionally, interfacial TEM characterization, thin-film (TF) XRD surface analysis, LogP determination, and a cytotoxicity assay were carried out. RESULTS FAM-201 revealed significantly higher μTBS than HEMA+ at 1w and 6 m when applied both in E&R and SE bonding modes. HEAA's μTBS was significantly lower than that of HEMA+ at 1w when applied in SE mode. TF-XRD and TEM revealed similar chemical and ultrastructural interfacial characterization, including stable 10-MDP_Ca salt nano-layering. FAM-201 was least cytotoxic and presented with an intermediary LogP, while HEAA presented with the highest LogP, indicating high hydrophilicity and water-sorption sensitivity. SIGNIFICANCE The acrylamide co-monomer FAM-201 could replace HEMA in an UA formulation, while HEAA not.
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Affiliation(s)
- M H Ahmed
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; Tanta University, Department of Dental Biomaterials, Tanta, Egypt
| | - K Yoshihara
- National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute, Takamatsu, Japan; Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - N Nagaoka
- Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - C Yao
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - A Matsukawa
- Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - Y Yoshida
- Hokkaido University, Faculty of Dental Medicine, Department of Biomaterials and Bioengineering, Sapporo, Hokkaido, Japan
| | - B Van Meerbeek
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium.
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Yoshihara K, Nagaoka N, Benino Y, Nakamura A, Hara T, Maruo Y, Yoshida Y, Van Meerbeek B. Touch-Cure Polymerization at the Composite Cement-Dentin Interface. J Dent Res 2021; 100:935-942. [PMID: 33771050 DOI: 10.1177/00220345211001020] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Ceramic restorations are often adhesively luted onto the tooth prep. The so-called touch-cure concept was developed to yield optimum polymerization of composite cement at the restoration-cement-tooth interface for immediate bond stabilization. Although this touch cure is theorized to initiate polymerization at the interface when the accelerator in the primer makes contact with the cement, this process has not yet been proven. This study aimed to elucidate the mechanism of touch cure by measuring the degree of conversion (DC) of composite cement applied with or without an accelerator-containing tooth primer (TP) versus an accelerator-free primer using real-time Fourier-transform infrared spectroscopy (RT-FTIR) and attenuated total reflection (ATR)-FTIR. Interfacial bond strength was measured in shear mode, the accelerator composition confirmed by X-ray fluorescence analysis (XRF), and the interfacial interaction of TP and composite cement with dentin investigated by X-ray diffraction (XRD), focused-ion-beam scanning electron microscopy (FIB-SEM) with 3-dimensional interface reconstruction, and transmission electron microscopy (TEM). RT/ATR-FTIR revealed the significantly highest DC when the composite cement was applied with the accelerator-containing primer. XRF disclosed a vanadium compound as a novel chemical accelerator within TP, instead of a classic chemical curing initiator system, to set off touch cure as soon the cement contacts the previously applied primer. Although the TP contains the acidic functional monomer 10-MDP for adhesion to tooth tissue, touch cure using the accelerator-containing TP combined the fastest/highest DC with the highest bond strength. FIB-SEM and TEM confirmed the tight interfacial interaction at dentin with submicron hybridization along with stable 10-MDP also Ca-salt nanolayering.
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Affiliation(s)
- K Yoshihara
- National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute, Takamatsu, Kagawa, Japan.,Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - N Nagaoka
- Okayama University Dental School, Advanced Research of Center for Oral and Craniofacial Science, Okayama, Japan
| | - Y Benino
- Okayama University, Graduate School of Environmental and Life Science, Okayama, Japan
| | - A Nakamura
- National Institute for Materials Science (NIMS), Electron Microscopy Analysis Station, Tsukuba, Ibaraki, Japan
| | - T Hara
- National Institute for Materials Science (NIMS), Electron Microscopy Analysis Station, Tsukuba, Ibaraki, Japan
| | - Y Maruo
- Department of Occlusion and Removable Prosthodontics, Okayama University Hospital, Okayama, Japan
| | - Y Yoshida
- Hokkaido University, Faculty of Dental Medicine, Department of Biomaterials and Bioengineering, Sapporo, Hokkaido, Japan
| | - B Van Meerbeek
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
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Abstract
X-ray diffraction (XRD) surface analysis and ultrastructural interfacial characterization using transmission electron microscopy (TEM) confirmed that the functional monomer 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) self-assembles into nano-layers at adhesive-tooth interfaces. Self-assembled nano-layering is thought to contribute to the durability of bonding to tooth dentin, although this has not been proven yet. In order to disclose this potential bond-durability contribution of nano-layering, we observed the 3-dimensional (3D) spreading of nano-layering by a series of focused-ion-beam (FIB) milled cross sections by scanning electron microscopy (FIB-SEM) and examined the mechanical properties of self-assembled nano-layering using scanning probe microscopy (SPM). A commercial 10-MDP-containing 3-step self-etch adhesive partially demineralized dentin up to submicron depth, forming a submicron hydroxyapatite-rich hybrid layer. TEM chemically and ultrastructurally confirmed the formation of interfacial nano-layering. FIB-SEM 3D reconstructions disclosed a 3D network of self-assembled nano-layering extending from the hybrid layer up to within the adjacent adhesive-resin layer. SPM revealed that nano-layering within the adhesive-resin layer possessed a higher elastic modulus than that of the surrounding adhesive resin, hereby suggesting that nano-layering contributes to the mechanical strength of adhesives like filler particles do. Nano-layering's 3D expanded structure is expected to strengthen the surrounding resin, as well to better interconnect the adhesive-resin layer to the hybrid layer. In conclusion, this exploratory study demonstrated that nano-layering constitutes a strong phase at the adhesive interface, which may contribute to the clinical longevity of the 10-MDP-based bond to dentin.
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Affiliation(s)
- K Yoshihara
- National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute, Takamatsu, Japan.,Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - N Nagaoka
- Okayama University Dental School, Advanced Research Center for Oral and Craniofacial Sciences, Okayama, Japan
| | - A Nakamura
- National Institute for Materials Science (NIMS), Electron Microscopy Analysis Station, Ibaraki, Japan
| | - T Hara
- National Institute for Materials Science (NIMS), Electron Microscopy Analysis Station, Ibaraki, Japan
| | - Y Yoshida
- Hokkaido University, Faculty of Dental Medicine, Department of Biomaterials and Bioengineering, Sapporo, Hokkaido, Japan
| | - B Van Meerbeek
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
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Ahmed MH, Yoshihara K, Yao C, Okazaki Y, Van Landuyt K, Peumans M, Van Meerbeek B. Multiparameter evaluation of acrylamide HEMA alternative monomers in 2-step adhesives. Dent Mater 2020; 37:30-47. [PMID: 33220993 DOI: 10.1016/j.dental.2020.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 07/16/2020] [Accepted: 10/02/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE As frequently added to adhesives, the mono-functional monomer 2-hydroxyethyl methacrylate (HEMA) acts as co-solvent and improves surface wetting. Nevertheless, HEMA promotes watersorption and hydrolysis at adhesive interfaces, affecting bond durability to dentin. This study investigated if two acrylamide co-monomer alternatives could replace HEMA in experimental adhesive-resin formulations as part of 3/2-step universal adhesives applied, respectively, in etch-and-rinse (E&R) and self-etch (SE) bonding modes. METHODS Upon priming dentin with the 10-MDP-based Clearfil SE Bond 2' primer ('C-SE2p'; Kuraray Noritake), three experimental adhesive resins, consisting of 50 wt.% Bis-GMA, 15 wt.% TEGDMA, and either 35 wt.% diethyl acrylamide ('DEAA'), hydroxyethyl acrylamide ('HEAA') or HEMA ('HEMA+'), were applied. The control HEMA-free adhesive resin contained 60 wt.% Bis-GMA and 40 wt.% TEGDMA ('HEMA-'). All adhesives were evaluated for 'immediate' and 'aged' micro-tensile bond strength (μTBS) to dentin upon, respectively, 1-week (1w) and 6-month (6m) water storage, TEM adhesive-dentin interfacial interaction, 24-h and 6m three-point bending, contact-angle wetting, viscosity and watersorption. RESULTS Linear mixed-effects model statistics revealed significantly better bonding performance of the adhesives applied in E&R than SE mode, except for DEAA_1w, with the highest μTBSs recorded for DEAA and HEMA- applied in SE mode. In E&R mode, aging did not significantly reduce DEAA's μTBS. Best wetting on primed dentin was recorded for HEMA+, significantly better than DEAA, further HEAA and HEMA-, these directly related to their viscosity. HEAA absorbed significantly more water than all other adhesive-resin formulations. HEMA->DEAA>HEAA>HEMA+ was the significant order for 6m bending strength. CONCLUSIONS The acrylamide co-monomer DEAA could replace HEMA, while HEAA not.
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Affiliation(s)
- M H Ahmed
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; Tanta University, Department of Dental Biomaterials, Tanta, Egypt
| | - K Yoshihara
- National Institute of Advanced Industrial Science and Technology (AIST), Health Research Institute, Kagawa, Japan; Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, Japan
| | - C Yao
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine Ministry of Education, Wuhan, China
| | - Y Okazaki
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium; Hiroshima University, Department of Advanced Prosthodontics, Hiroshima, Japan
| | - K Van Landuyt
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - M Peumans
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium
| | - B Van Meerbeek
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Leuven, Belgium.
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van den Breemer C, Özcan M, Cune MS, Ayres AA, Van Meerbeek B, Gresnigt M. Effect of Immediate Dentin Sealing and Surface Conditioning on the Microtensile Bond Strength of Resin-based Composite to Dentin. Oper Dent 2019; 44:E289-E298. [PMID: 31084533 DOI: 10.2341/18-052-l] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study evaluated the microtensile bond strength (μTBS) of resin-based composite (RBC) to dentin after different immediate dentin sealing (IDS) strategies and surface-conditioning (SC) methods and on two water storage times. Human molars (n=48) were randomly divided into eight experimental groups involving four different IDS strategies-IDS-1L with one layer of adhesive, IDS-2L with two layers of adhesive, IDS-F with one layer of adhesive and one layer of flowable RBC, and DDS (delayed dentin sealing) with no layer of adhesive (control)-and two different SC methods-SC-P with pumice rubbing and SC-PC with pumice rubbing followed by tribochemical silica coating. The μTBS test was performed after one week and after six months of water storage, being recorded as the "immediate" and "aged" μTBS, respectively. Composite-adhesive-dentin microspecimens (0.9×0.9×8-9 mm) were stressed in tension until failure to determine the μTBS. Failure mode and location of failure were categorized. Two-way analysis of variance was applied to analyze the data for statistically significant differences between the experimental groups (p<0.05). Two-way analysis of variance revealed no significant differences between the one-week μTBS specimens for IDS strategy (p=0.087) and SC methods (p=0.806). However, the interaction of IDS strategy and SC methods appeared statistically significant (p=0.016). The six-month specimen evaluation showed no significant difference in μTBS for SC (p=0.297) and SC/IDS interaction (p=0.055), but the μTBS of the IDS strategies differed significantly among them (p=0.003). For tribochemical silica-coated IDS, no significant effect of aging on μTBS was recorded (p=0.465), but there was a highly significant difference in μTBS depending on the IDS strategy (p<0.001). In addition, the interaction of IDS and aging was borderline statistically significant (p=0.045). The specimens failed mainly at the adhesive-dentin interface for all experimental groups. Dentin exposure during clinical procedures for indirect restorations benefits from the application of IDS, which was shown to result in higher bond strength. No significant differences were found between cleaning with solely pumice or pumice followed by tribochemical silica coating.
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Hardy C, Landreau V, Valassis M, Mercelis B, Van Meerbeek B, Leprince J. Mini-interfacial fracture toughness when bonding indirect restorations with light-curable composite. Dent Mater 2019. [DOI: 10.1016/j.dental.2019.08.090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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10
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Ayres AP, Freitas PH, De Munck J, Vananroye A, Clasen C, Dias CDS, Giannini M, Van Meerbeek B. Benefits of Nonthermal Atmospheric Plasma Treatment on Dentin Adhesion. Oper Dent 2018; 43:E288-E299. [PMID: 30457947 DOI: 10.2341/17-123-l] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES: This study aimed to evaluate the influence of two nonthermal atmospheric plasma (NTAP) application times and two storage times on the microtensile bond strength (μTBS) to dentin. The influence of NTAP on the mechanical properties of the dentin-resin interface was studied by analyzing nanohardness (NH) and Young's modulus (YM). Water contact angles of pretreated dentin and hydroxyapatite blocks were also measured to assess possible alterations in the surface hydrophilicity upon NTAP. METHODS AND MATERIALS: Forty-eight human molars were used in a split-tooth design (n=8). Midcoronal exposed dentin was flattened by a 600-grit SiC paper. One-half of each dentin surface received phosphoric acid conditioning, while the other half was covered with a metallic barrier and remained unetched. Afterward, NTAP was applied on the entire dentin surface (etched or not) for 10 or 30 seconds. The control groups did not receive NTAP treatment. Scotchbond Universal (SBU; 3M ESPE) and a resin-based composite were applied to dentin following the manufacturer's instructions. After 24 hours of water storage at 37°C, the specimens were sectioned perpendicular to the interface to obtain approximately six specimens or bonded beams (approximately 0.9 mm2 in cross-sectional area) representing the etch-and-rinse (ER) approach and another six specimens representing the self-etch (SE) approach. Half of the μTBS specimens were immediately loaded until failure, while the other half were first stored in deionized water for two years. Three other bonded teeth were selected from each group (n=3) for NH and YM evaluation. Water contact-angle analysis was conducted using a CAM200 (KSV Nima) goniometer. Droplet images of dentin and hydroxyapatite surfaces with or without 10 or 30 seconds of plasma treatment were captured at different water-deposition times (5 to 55 seconds). RESULTS: Two-way analysis of variance revealed significant differences in μTBS of SBU to dentin after two years of water storage in the SE approach, without differences among treatments. After two years of water aging, the ER control and ER NTAP 10-second groups showed lower μTBS means compared with the ER NTAP 30-second treated group. Nonthermal atmospheric plasma resulted in higher NH and YM for the hybrid layer. The influence of plasma treatment in hydrophilicity was more evident in the hydroxyapatite samples. Dentin hydrophilicity increased slightly after 10 seconds of NTAP, but the difference was higher when the plasma was used for 30 seconds. CONCLUSIONS: Dentin NTAP treatment for 30 seconds contributed to higher μTBS after two years of water storage in the ER approach, while no difference was observed among treatments in the SE evaluation. This result might be correlated to the increase in nanohardness and Young's modulus of the hybrid layer and to better adhesive infiltration, since dentin hydrophilicity was also improved. Although some effects were observed using NTAP for 10 seconds, the results suggest that 30 seconds is the most indicated treatment time.
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Abstract
Besides chemically interacting with hard tooth tissue, acidic functional monomers of self-etch adhesives should etch the prepared tooth surface to dissolve the smear layer and to provide surface micro-retention. Although the etching efficacy of functional monomers is commonly determined in terms of pH, the pH of adhesives cannot accurately be measured. Better is to measure the hydroxyapatite (HAp)-dissolving capacity, also considering that functional monomers may form monomer-Ca salts. Here, the etching efficacy of 6 functional monomers (GPDM, phenyl-P, MTEGP, 4-META, 6-MHP and 10-MDP) was investigated. Solutions containing 15 wt% monomer, 45 wt% ethanol, and 40 wt% water were prepared. Initially, we observed enamel surfaces exposed to monomer solution by scanning electron microscopy (SEM). X-ray diffraction (XRD) was employed to detect monomer-Ca salt formation. Phenyl-P exhibited a strong etching effect, while 10-MDP-treated enamel showed substance deposition, which was identified by XRD as 10-MDP-Ca salt. To confirm these SEM/XRD findings, we determined the etching efficacy of functional monomers by measuring both the concentration of Ca released from HAp using inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and the amount of monomer-Ca salt formation using 31P magic-angle spinning (MAS) nuclear magnetic resonance (NMR). ICP-AES revealed that the highest Ca concentration was produced by phenyl-P and the lowest Ca concentration, almost equally, by 4-META and 10-MDP. Only 10-MDP formed 10-MDP-Ca salts, indicating that 10-MDP released more Ca from HAp than was measured by ICP-AES. Part of the released Ca was consumed to form 10-MDP-Ca salts. It is concluded that the repeatedly reported higher bonding effectiveness of 10-MDP-based adhesives must not only be attributed to the more intense chemical bonding of 10-MDP but also to its higher etching potential, a combination the other functional monomers investigated lack.
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Affiliation(s)
- K Yoshihara
- 1 Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan
| | - S Hayakawa
- 2 Biomaterials Laboratory, Graduate School of Natural Science and Technology, Okayama University, Kita-ku, Okayama, Japan
| | - N Nagaoka
- 3 Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Kita-ku, Okayama, Japan
| | - T Okihara
- 4 Division of Chemical and Biological Technology, Graduate School of Natural Science and Technology, Okayama University, Kita-ku, Okayama, Japan
| | - Y Yoshida
- 5 Department of Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - B Van Meerbeek
- 6 KU Leuven (University of Leuven), Department of Oral Health Research, BIOMAT & University Hospitals Leuven, Dentistry, Leuven, Belgium
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Cokic S, Duca R, Godderis L, Hoet P, Seo J, Van Meerbeek B, Van Landuyt K. Release of monomers from composite dust. J Dent 2017; 60:56-62. [DOI: 10.1016/j.jdent.2017.02.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 02/21/2017] [Accepted: 02/27/2017] [Indexed: 10/20/2022] Open
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13
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Zhang F, Chevalier J, Olagnon C, Batuk M, Hadermann J, Van Meerbeek B, Vleugels J. Grain-Boundary Engineering for Aging and Slow-Crack-Growth Resistant Zirconia. J Dent Res 2017; 96:774-779. [PMID: 28571511 DOI: 10.1177/0022034517698661] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Ceramic materials are prone to slow crack growth, resulting in strength degradation over time. Although yttria-stabilized zirconia (Y-TZP) ceramics have higher crack resistance than other dental ceramics, their aging susceptibility threatens their long-term performance in aqueous environments such as the oral cavity. Unfortunately, increasing the aging resistance of Y-TZP ceramics normally reduces their crack resistance. Our recently conducted systematic study of doping 3Y-TZP with various trivalent cations revealed that lanthanum oxide (La2O3) and aluminum oxide (Al2O3) have the most potent effect to retard the aging kinetics of 3Y-TZP. In this study, the crack-propagation behavior of La2O3 and Al2O3 co-doped 3Y-TZP ceramics was investigated by double-torsion methods. The grain boundaries were examined using scanning transmission electron microscopy and energy-dispersive spectroscopy (STEM-EDS). Correlating these analytic data with hydrothermal aging studies using different doping systems, a strategy to strongly bind the segregated dopant cations with the oxygen vacancies at the zirconia-grain boundary was found to improve effectively the aging resistance of Y-TZP ceramics without affecting the resistance to crack propagation.
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Affiliation(s)
- F Zhang
- 1 KU Leuven (University of Leuven), Department of Materials Engineering, Heverlee, Belgium.,2 KU Leuven (University of Leuven) & Dentistry, BIOMAT, Department of Oral Health Sciences, University Hospitals Leuven, Leuven, Belgium
| | - J Chevalier
- 3 University of Lyon, UMR CNRS 5510 (MATEIS), INSA de Lyon, France
| | - C Olagnon
- 3 University of Lyon, UMR CNRS 5510 (MATEIS), INSA de Lyon, France
| | - M Batuk
- 4 University of Antwerp, Electron Microscopy for Materials Science (EMAT), Antwerp, Belgium
| | - J Hadermann
- 4 University of Antwerp, Electron Microscopy for Materials Science (EMAT), Antwerp, Belgium
| | - B Van Meerbeek
- 2 KU Leuven (University of Leuven) & Dentistry, BIOMAT, Department of Oral Health Sciences, University Hospitals Leuven, Leuven, Belgium
| | - J Vleugels
- 1 KU Leuven (University of Leuven), Department of Materials Engineering, Heverlee, Belgium
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14
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Lise DP, Van Ende A, De Munck J, Vieira LCC, Baratieri LN, Van Meerbeek B. Microtensile Bond Strength of Composite Cement to Novel CAD/CAM Materials as a Function of Surface Treatment and Aging. Oper Dent 2017; 42:73-81. [DOI: 10.2341/15-263-l] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
Objectives: To evaluate the effect of different surface treatments on the bond strength to a composite and a polymer-infiltrated ceramic CAD/CAM block after six-month artificial aging.
Methods and Materials: Two types of CAD/CAM blocks (Cerasmart, GC; Enamic, Vita Zahnfabrik) were cut in slabs of 4-mm thickness, divided into six groups, and subjected to the following surface treatments: group 1: no treatment; group 2: sandblasting (SB); group 3: SB + silane (Si); group 4: SB + Si + flowable composite (see below); group 5: 5% hydrofluoric acid etching (HF) + Si; and group 6: 37% phosphoric acid etching (H3PO4) + Si. Sections of the same group were luted together (n=3: 3 sandwich specimens/group) using a dual-cure self-adhesive cement for all groups, except for the sections of group 4 that were luted using a light-curing flowable composite. After three weeks of storage in 0.5% chloramine at 37°C, the sandwich specimens were sectioned in rectangular microspecimens and trimmed at the interface to a dumbbell shape (1.1-mm diameter). One half of the specimens was subjected to a microtensile bond strength (μTBS) test, and the other half was tested after six months of water storage (aging). Data were statistically analyzed with a linear mixed-effects model for the factors surface treatment, material type, and aging, together with their first-degree interactions (α=0.05).
Results: The lowest bond strengths were obtained in the absence of any surface treatment (group 1), while the highest μTBSs were obtained when the surface was roughened by either SB or HF, this in combination with chemical adhesion through Si. Loss in bond strength was observed after six-month aging when either surface roughening or silanization, or both, were omitted.
Conclusions: Both the composite and polymer-infiltrated ceramic CAD/CAM blocks appeared equally bonding-receptive regardless of the surface treatment used. Creating a microretentive surface by either SB or HF, followed by chemical adhesion using Si, is mandatory to maintain the bond strength after six months.
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Affiliation(s)
- DP Lise
- Diogo Pedrollo Lise, DDS, MSD, PhD, Department of Operative Dentistry, Federal University of Santa Catarina (UFSC), Santa Catarina, Brazil
| | | | - J De Munck
- Jan De Munck, DDS, MSD, PhD, postdoctoral research fellow, KU Leuven – BIOMAT, Department of Oral Health Sciences, KU Leuven and Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - LCC Vieira
- Luiz Clovis Cardoso Vieira, DDS, MSD, PhD, professor emeritus, Department of Operative Dentistry, Federal University of Santa Catarina (UFSC), Santa Catarina, Brazil
| | - LN Baratieri
- Luiz Narciso Baratieri, DDS, MSD, PhD, professor emeritus, Department of Operative Dentistry, Federal University of Santa Catarina (UFSC), Santa Catarina, Brazil
| | - B Van Meerbeek
- Bart Van Meerbeek, DDS, MSD, PhD, full professor, KU Leuven – BIOMAT, Department of Oral Health Sciences, KU Leuven and Dentistry, University Hospitals Leuven, Leuven, Belgium
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15
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Inoue S, Koshiro K, Yoshida Y, De Munck J, Nagakane K, Suzuki K, Sano H, Van Meerbeek B. Hydrolytic Stability of Self-etch Adhesives Bonded to Dentin. J Dent Res 2016; 84:1160-4. [PMID: 16304447 DOI: 10.1177/154405910508401213] [Citation(s) in RCA: 192] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Functional monomers chemically interact with hydroxyapatite that remains within submicron hybrid layers produced by mild self-etch adhesives. The functional monomer 10-MDP interacts most intensively with hydroxyapatite, and its calcium salt appeared most hydrolytically stable, as compared with 4-MET and phenyl-P. We investigated the hypothesis that additional chemical interaction of self-etch adhesives improves bond stability. The micro-tensile bond strength (μTBS) of the 10-MDP-based adhesive did not decrease significantly after 100,000 cycles, but did after 50,000 and 30,000 cycles, respectively, for the 4-MET-based and the phenyl-P-based adhesives. Likewise, the interfacial ultrastructure was unchanged after 100,000 thermocycles for the 10-MDP-based adhesive, while that of both the 4-MET- and phenyl-P-based adhesives contained voids and less-defined collagen. The findings of this study support the concept that long-term durability of adhesive-dentin bonds depends on the chemical bonding potential of the functional monomer.
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Affiliation(s)
- S Inoue
- Division for General Dentistry, Center for Dental Clinics, Hokkaido University Hospital, Kita 13 Nishi 7, Kita-ku, Sapporo 060-8586, Japan
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16
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Coutinho E, Van Landuyt K, De Munck J, Poitevin A, Yoshida Y, Inoue S, Peumans M, Suzuki K, Lambrechts P, Van Meerbeek B. Development of a Self-etch Adhesive for Resin-modified Glass Ionomers. J Dent Res 2016; 85:349-53. [PMID: 16567557 DOI: 10.1177/154405910608500413] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The favorable self-adhesiveness of resin-modified glass ionomers (RMGIs) might be even further improved if the time-consuming and technically sensitive etch-and-rinse pre-treatment step with polyalkenoic acids could be avoided. We undertook this study to assess the effectiveness of an experimental self-etch adhesive for RMGIs that does not need to be rinsed off. Ultrastructural analysis and micro-tensile bond strength testing to enamel and dentin of a RMGI restorative material and a RMGI adhesive were performed after 4 different surface pre-treatments: no conditioning; 25% polyalkenoic acid; an experimental self-etch adhesive; and 37.5% phosphoric acid followed by the experimental self-etch adhesive. The use of an experimental self-etch adhesive increased the bond strength of RMGIs, especially after an additional conditioning step. Interfacial analysis showed the formation of a thin hydroxyapatite-containing hybrid layer. The self-etch technique enhances the user-friendliness of RMGIs and lowers their technique-sensitivity, while maintaining desirable characteristics of the conventional etch-and-rinse approach with polyalkenoic acids.
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Affiliation(s)
- E Coutinho
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, B-3000 Leuven, Belgium
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17
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De Munck J, Van Landuyt K, Peumans M, Poitevin A, Lambrechts P, Braem M, Van Meerbeek B. A Critical Review of the Durability of Adhesion to Tooth Tissue: Methods and Results. J Dent Res 2016; 84:118-32. [PMID: 15668328 DOI: 10.1177/154405910508400204] [Citation(s) in RCA: 958] [Impact Index Per Article: 119.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The immediate bonding effectiveness of contemporary adhesives is quite favorable, regardless of the approach used. In the long term, the bonding effectiveness of some adhesives drops dramatically, whereas the bond strengths of other adhesives are more stable. This review examines the fundamental processes that cause the adhesion of biomaterials to enamel and dentin to degrade with time. Non-carious class V clinical trials remain the ultimate test method for the assessment of bonding effectiveness, but in addition to being high-cost, they are time- and labor-consuming, and they provide little information on the true cause of clinical failure. Therefore, several laboratory protocols were developed to predict bond durability. This paper critically appraises methodologies that focus on chemical degradation patterns of hydrolysis and elution of interface components, as well as mechanically oriented test set-ups, such as fatigue and fracture toughness measurements. A correlation of in vitro and in vivo data revealed that, currently, the most validated method to assess adhesion durability involves aging of micro-specimens of biomaterials bonded to either enamel or dentin. After about 3 months, all classes of adhesives exhibited mechanical and morphological evidence of degradation that resembles in vivo aging effects. A comparison of contemporary adhesives revealed that the three-step etch-and-rinse adhesives remain the ‘gold standard’ in terms of durability. Any kind of simplification in the clinical application procedure results in loss of bonding effectiveness. Only the two-step self-etch adhesives approach the gold standard and do have some additional clinical benefits.
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Affiliation(s)
- J De Munck
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
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18
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Van Landuyt KL, Cokic SM, Asbach C, Hoet P, Godderis L, Reichl FX, Van Meerbeek B, Vennemann A, Wiemann M. Interaction of rat alveolar macrophages with dental composite dust. Part Fibre Toxicol 2016; 13:62. [PMID: 27888833 PMCID: PMC5124269 DOI: 10.1186/s12989-016-0174-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 11/10/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dental composites have become the standard filling material to restore teeth, but during the placement of these restorations, high amounts of respirable composite dust (<5 μm) including many nano-sized particles may be released in the breathing zone of the patient and dental operator. Here we tested the respirable fraction of several composite particles for their cytotoxic effect using an alveolar macrophage model system. METHODS: Composite dust was generated following a clinical protocol, and the dust particles were collected under sterile circumstances. Dust was dispersed in fluid, and 5-μm-filtered to enrich the respirable fractions. Quartz DQ12 and corundum were used as positive and negative control, respectively. Four concentrations (22.5 μg/ml, 45 μg/ml, 90 μg/ml and 180 μg/ml) were applied to NR8383 alveolar macrophages. Light and electron microscopy were used for subcellular localization of particles. Culture supernatants were tested for release of lactate dehydrogenase, glucuronidase, TNF-α, and H2O2. RESULTS Characterization of the suspended particles revealed numerous nano-sized particles but also many high volume particles, most of which could be removed by filtering. Even at the highest concentration (180 μg/ml), cells completely cleared settled particles from the bottom of the culture vessel. Accordingly, a mixture of nano- and micron-scaled particles was observed inside cells where they were confined to phagolysosomes. The filtered particle fractions elicited largely uniform dose-dependent responses, which were elevated compared to the control only at the highest concentration, which equaled a mean cellular dose of 120 pg/cell. A low inflammatory potential was identified due to dose-dependent release of H2O2 and TNF-α. However, compared to the positive control, the released levels of H2O2 and TNF-α were still moderate, but their release profiles depended on the type of composite. CONCLUSIONS Alveolar macrophages are able to phagocytize respirable composite dust particle inclusive nanoparticles. Since NR8383 cells tolerate a comparatively high cell burden (60 pg/cell) of each of the five materials with minimal signs of cytotoxicity or inflammation, the toxic potential of respirable composite dust seems to be low. These results are reassuring for dental personnel, but more research is needed to characterize the actual exposure and uptake especially of the pure nano fraction.
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Affiliation(s)
- K L Van Landuyt
- KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, Leuven, 3000, Belgium.
| | - S M Cokic
- KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, Leuven, 3000, Belgium
| | - C Asbach
- Institute of Energy and Environmental Technology (IUTA) e.V, BliersheimerStraße 58-60, Duisburg, 47229, Germany
| | - P Hoet
- Research Unit Experimental Toxicology, Center for Environmental and Health Research, Department of Public Health and Primary Care, University of Leuven, Herestraat 49, Leuven, 3001, Belgium
| | - L Godderis
- Research Unit Experimental Toxicology, Center for Environmental and Health Research, Department of Public Health and Primary Care, University of Leuven, Herestraat 49, Leuven, 3001, Belgium
| | - F X Reichl
- Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University of Munich, Nussbaumstraße 26, Munich, 80336, Germany
| | - B Van Meerbeek
- KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, Leuven, 3000, Belgium
| | - A Vennemann
- IBE, IBE R&D gGmbH, Mendelstraße 11, Münster, 48149, Germany
| | - M Wiemann
- IBE, IBE R&D gGmbH, Mendelstraße 11, Münster, 48149, Germany
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Coutinho E, Yoshida Y, Inoue S, Fukuda R, Snauwaert J, Nakayama Y, De Munck J, Lambrechts P, Suzuki K, Van Meerbeek B. Gel Phase Formation at Resin-modified Glass-ionomer/Tooth Interfaces. J Dent Res 2016; 86:656-61. [PMID: 17586714 DOI: 10.1177/154405910708600714] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Ionic bonding between polyalkenoic acid and hydroxyapatite may explain the excellent bonding retention of glass-ionomers in clinical trials. We have here investigated the extent to which the self-adhesiveness of resin-modified glass-ionomers (RMGIs) can be attributed to this chemical bonding capacity. Therefore, the interaction of 3 RMGIs with tooth substrates was comprehensively characterized, with electron and atomic force microscopy correlated with x-ray photoelectron spectroscopy (XPS). Interfacial ultrastructural analysis for 2 RMGIs disclosed a shallow hybridization of hydroxyapatite-coated collagen, on which a submicron gel phase was deposited through reaction of the polyalkenoic acid with calcium extracted from the dentin surface. One RMGI, however, bonded to dentin without hybrid layer or gel phase formation. XPS indicated that polycarboxylic acids included in the RMGIs electrostatically interacted with hydroxyapatite. We conclude that the self-adhesiveness of RMGIs should be attributed to ionic bonding to hydroxyapatite around collagen, and to micro-mechanical interlocking for those RMGIs that additionally hybridize dentin.
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Affiliation(s)
- E Coutinho
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Leuven, Belgium
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20
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Yoshida Y, Nagakane K, Fukuda R, Nakayama Y, Okazaki M, Shintani H, Inoue S, Tagawa Y, Suzuki K, De Munck J, Van Meerbeek B. Comparative Study on Adhesive Performance of Functional Monomers. J Dent Res 2016; 83:454-8. [PMID: 15153451 DOI: 10.1177/154405910408300604] [Citation(s) in RCA: 644] [Impact Index Per Article: 80.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Mild self-etch adhesives demineralize dentin only partially, leaving hydroxyapatite around collagen within a submicron hybrid layer. We hypothesized that this residual hydroxyapatite may serve as a receptor for chemical interaction with the functional monomer and, subsequently, contribute to adhesive performance in addition to micro-mechanical hybridization. We therefore chemically characterized the adhesive interaction of 3 functional monomers with synthetic hydroxyapatite, using x-ray photoelectron spectroscopy and atomic absorption spectrophotometry. We further characterized their interaction with dentin ultra-morphologically, using transmission electron microscopy. The monomer 10-methacryloxydecyl dihydrogen phosphate (10-MDP) readily adhered to hydroxyapatite. This bond appeared very stable, as confirmed by the low dissolution rate of its calcium salt in water. The bonding potential of 4-methacryloxyethyl trimellitic acid (4-MET) was substantially lower. The monomer 2-methacryloxyethyl phenyl hydrogen phosphate (phenyl-P) and its bond to hydroxyapatite did not appear to be hydrolytically stable. Besides self-etching dentin, specific functional monomers have additional chemical bonding efficacy that is expected to contribute to their adhesive potential to tooth tissue.
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Affiliation(s)
- Y Yoshida
- Department of Biomaterials, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8525, Japan
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Pongprueksa P, De Munck J, Karunratanakul K, Barreto B, Van Ende A, Senawongse P, Van Meerbeek B. Response to Letter to the Editor, “Dentin Bonding Testing Using a Mini-interfacial Fracture Toughness Approach”. J Dent Res 2016; 95:954. [DOI: 10.1177/0022034516652127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- P. Pongprueksa
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT and University Hospitals Leuven, Dentistry, Leuven, Belgium
- Department of Operative Dentistry and Endodontics, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - J. De Munck
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT and University Hospitals Leuven, Dentistry, Leuven, Belgium
| | - K. Karunratanakul
- National Metal and Materials Technology Center, National Science and Technology Development Agency, Pathumthani, Thailand
| | - B.C. Barreto
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT and University Hospitals Leuven, Dentistry, Leuven, Belgium
| | - A. Van Ende
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT and University Hospitals Leuven, Dentistry, Leuven, Belgium
| | - P. Senawongse
- Department of Operative Dentistry and Endodontics, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - B. Van Meerbeek
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT and University Hospitals Leuven, Dentistry, Leuven, Belgium
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Nedeljkovic I, De Munck J, Slomka V, Van Meerbeek B, Teughels W, Van Landuyt K. Lack of Buffering by Composites Promotes Shift to More Cariogenic Bacteria. J Dent Res 2016; 95:875-81. [DOI: 10.1177/0022034516647677] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Secondary caries (SC) remains a very important problem with composite restorations. The objectives of this study were to test the acid-buffering ability of several restorative materials and to evaluate whether buffering of the restorative material has an impact on the microbial composition of the biofilm. Disk-shaped specimens of conventional composite, composite with surface prereacted glass-ionomer filler particles (so-called giomer), glass-ionomer cement (GIC), amalgam, and hydroxyapatite (HAp) (control) were exposed to aqueous solutions with pH 4, 5, 6, and 7 and to the medium containing bacteria-produced acids, and pH changes were recorded over several days. Next, material specimens were immersed in bacterial growth medium with pH adjusted to 5. After a 24-h incubation, the extracts were collected and inoculated with a cariogenic ( Streptococcus mutans) and a noncariogenic ( Streptococcus sanguinis) species. The bacterial growth was monitored both in a single-species model by spectrophotometry and in a dual-species model by viability quantitative polymerase chain reaction. Amalgam and HAp showed the strongest acid-buffering ability, followed by the GIC and the giomer, while the conventional composite did not exhibit any buffering capacity. Furthermore, due to the lack of acid-buffering abilities, composite was not able to increase the pH of the medium (pH 5), which, in the absence of antibacterial properties, allowed the growth of S. mutans, while the growth of S. sanguinis, a less aciduric species, was completely inhibited. A similar effect was observed when bacteria were cultured together: there was a higher percentage of S. mutans and lower percentage of S. sanguinis with the conventional composite than with other materials and HAp. In conclusion, conventional composites lack the ability to increase the local pH, which leads to the outgrowth of more acidogenic/aciduric bacteria and higher cariogenicity of the biofilm. Together with lack of antibacterial properties, lack of buffering may account for the higher susceptibility of composites to SC.
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Affiliation(s)
- I. Nedeljkovic
- KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Leuven, Belgium
| | - J. De Munck
- KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Leuven, Belgium
| | - V. Slomka
- Oral Microbiology, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Leuven, Belgium
| | - B. Van Meerbeek
- KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Leuven, Belgium
| | - W. Teughels
- Oral Microbiology, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Leuven, Belgium
| | - K.L. Van Landuyt
- KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Leuven, Belgium
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Ayres A, Pongprueksa P, De Munck J, Vananroye A, Clasen C, Nascimento F, Giannini M, Van Meerbeek B. Mini-interfacial fracture toughness of adhesive-dentin interfaces after plasma pre-treatment. Dent Mater 2016. [DOI: 10.1016/j.dental.2016.08.154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Pongprueksa P, De Munck J, Karunratanakul K, Barreto B, Van Ende A, Senawongse P, Van Meerbeek B. Dentin Bonding Testing Using a Mini-interfacial Fracture Toughness Approach. J Dent Res 2015; 95:327-33. [DOI: 10.1177/0022034515618960] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Measurement of interfacial fracture toughness (iFT) is considered a more valid method to assess bonding effectiveness as compared with conventional bond strength testing. Common fracture toughness tests are, however, laborious and require a relatively bulky specimen size. This study aimed to evaluate a new simplified and miniaturized iFT (mini-iFT) test. Four dentin adhesives, representing the main adhesive classes, and 1 glass ionomer cement were applied onto flat dentin. Mini-iFT (1.5 × 2.0 × 16 to 18 mm) and microtensile bond strength (µTBS; 1.5 × 1.5 × 16 to 18 mm) specimens were prepared from the same tooth. For the mini-iFT specimens, a single notch was cut at the adhesive-dentin interface with a 150-µm diamond blade under water cooling; the specimens were loaded until failure in a 4-point bending test setup. Finite element analysis was used to analyze stress distribution during mini-iFT testing. The correlation between the mean mini-iFT and µTBS was examined and found to be significant; a strong positive correlation was found ( r2 = 0.94, P = 0.004). Weibull data analysis suggested the mini-iFT to vary less than the µTBS. Both the mini-iFT and the µTBS revealed the same performance order, with the 3-step etch-and-rinse adhesive outperforming the 2-step self-etch and 2-step etch-and-rinse adhesive, followed by the 1-step SE adhesive and, finally, the glass ionomer cement. Scanning electron microscopy failure analysis revealed the adhesive-dentin interface to fail more at the actual interface with the mini-iFT test, while µTBS specimens failed more within dentin and composite. This finding was corroborated by finite element analysis showing stress to concentrate at the interface during mini-iFT loading and crack propagation. In conclusion, the new mini-iFT test appeared more discriminative and valid than the µTBS to assess bonding effectiveness; the latter test nevertheless remains more versatile. Specimen size and workload were alike, making the mini-iFT test a valid alternative for the popular µTBS test.
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Affiliation(s)
- P. Pongprueksa
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven), and Dentistry, University Hospitals Leuven, Leuven, Belgium
- Department of Operative Dentistry and Endodontics, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - J. De Munck
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven), and Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - K. Karunratanakul
- National Metal and Materials Technology Center, National Science and Technology Development Agency, Pathumthani, Thailand
| | - B.C. Barreto
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven), and Dentistry, University Hospitals Leuven, Leuven, Belgium
- BMGO, Biomechanics Section, Department of Mechanical Engineering, KU Leuven (University of Leuven), Leuven, Belgium
| | - A. Van Ende
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven), and Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - P. Senawongse
- Department of Operative Dentistry and Endodontics, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - B. Van Meerbeek
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven), and Dentistry, University Hospitals Leuven, Leuven, Belgium
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Inokoshi M, Yoshihara K, Nagaoka N, Nakanishi M, De Munck J, Minakuchi S, Vanmeensel K, Zhang F, Yoshida Y, Vleugels J, Naert I, Van Meerbeek B. Structural and Chemical Analysis of the Zirconia–Veneering Ceramic Interface. J Dent Res 2015; 95:102-9. [DOI: 10.1177/0022034515608825] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The interfacial interaction of veneering ceramic with zirconia is still not fully understood. This study aimed to characterize morphologically and chemically the zirconia–veneering ceramic interface. Three zirconia-veneering conditions were investigated: 1) zirconia–veneering ceramic fired on sandblasted zirconia, 2) zirconia–veneering ceramic on as-sintered zirconia, and 3) alumina–veneering ceramic (lower coefficient of thermal expansion [CTE]) on as-sintered zirconia. Polished cross-sectioned ceramic–veneered zirconia specimens were examined using field emission gun scanning electron microscopy (Feg-SEM). In addition, argon-ion thinned zirconia–veneering ceramic interface cross sections were examined using scanning transmission electron microscopy (STEM)–energy dispersive X-ray spectrometry (EDS) at high resolution. Finally, the zirconia–veneering ceramic interface was quantitatively analyzed for tetragonal-to-monoclinic phase transformation and residual stress using micro-Raman spectroscopy (µRaman). Feg-SEM revealed tight interfaces for all 3 veneering conditions. High-resolution transmission electron microscopy (HRTEM) disclosed an approximately 1.0-µm transformed zone at sandblasted zirconia, in which distinct zirconia grains were no longer observable. Straight grain boundaries and angular grain corners were detected up to the interface of zirconia– and alumina–veneering ceramic with as-sintered zirconia. EDS mapping disclosed within the zirconia–veneering ceramic a few nanometers thick calcium/aluminum-rich layer, touching the as-sintered zirconia base, with an equally thick silicon-rich/aluminum-poor layer on top. µRaman revealed t-ZrO2-to- m-ZrO2 phase transformation and residual compressive stress at the sandblasted zirconia surface. The difference in CTE between zirconia– and the alumina–veneering ceramic resulted in residual tensile stress within the zirconia immediately adjacent to its interface with the veneering ceramic. The rather minor chemical elemental shifts recorded in the veneering ceramic did not suffice to draw definitive conclusions regarding potential chemical interaction of the veneering ceramic with zirconia. Sandblasting damaged the zirconia surface and induced phase transformation that also resulted in residual compressive stress. Difference in CTE of zirconia versus that of the veneering ceramic resulted in an unfavorable residual tensile stress at the zirconia–veneering ceramic interface.
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Affiliation(s)
- M. Inokoshi
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Leuven, Belgium
- Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - K. Yoshihara
- Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan
| | - N. Nagaoka
- Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Okayama, Japan
| | - M. Nakanishi
- Inorganic Materials Chemistry Laboratory, Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - J. De Munck
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - S. Minakuchi
- Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - K. Vanmeensel
- Department of Materials Engineering, KU Leuven (University of Leuven), Heverlee, Belgium
| | - F. Zhang
- Department of Materials Engineering, KU Leuven (University of Leuven), Heverlee, Belgium
| | - Y. Yoshida
- Department of Biomaterials and Bioengineering, Graduate School of Dental Medicine, Hokkaido University, Hokkaido, Japan
| | - J. Vleugels
- Department of Materials Engineering, KU Leuven (University of Leuven), Heverlee, Belgium
| | - I. Naert
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - B. Van Meerbeek
- BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Leuven, Belgium
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26
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Peumans M, De Munck J, Van Landuyt K, Van Meerbeek B. Thirteen-year randomized controlled clinical trial of a two-step self-etch adhesive in non-carious cervical lesions. Dent Mater 2015; 31:308-14. [DOI: 10.1016/j.dental.2015.01.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 12/30/2014] [Accepted: 01/07/2015] [Indexed: 01/30/2023]
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27
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Pongprueksa P, Miletic V, De Munck J, Brooks NR, Meersman F, Nies E, Van Meerbeek B, Van Landuyt KL. Effect of Evaporation on the Shelf Life of a Universal Adhesive. Oper Dent 2014; 39:500-7. [DOI: 10.2341/13-195] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
Objectives
The purpose of this study was to evaluate how evaporation affects the shelf life of a one-bottle universal adhesive.
Methods
Three different versions of Scotchbond Universal (SBU, 3M ESPE, Seefeld, Germany) were prepared using a weight-loss technique. SBU0 was left open to the air until maximal weight loss was obtained, whereas SBU50 was left open until 50% of evaporation occurred. In contrast, SBU100 was kept closed and was assumed to contain the maximum concentration of all ingredients. The degree of conversion (DC) was determined by using Fourier transform infrared spectroscopy on different substrates (on dentin or glass plate and mixed with dentin powder); ultimate microtensile strength and microtensile bond strength to dentin were measured as well.
Results
DC of the 100% solvent-containing adhesive (SBU100) was higher than that of the 50% (SBU50) and 0% (SBU0) solvent-containing adhesives for all substrates. DC of the adhesive applied onto glass and dehydrated dentin was higher than that applied onto dentin. Even though the ultimate microtensile strength of SBU0 was much higher than that of SBU50 and SBU100, its bond strength to dentin was significantly lower.
Conclusions
Evaporation of adhesive ingredients may jeopardize the shelf life of a one-bottle universal system by reducing the degree of conversion and impairing bond strength. However, negative effects only became evident after more than 50% evaporation.
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Affiliation(s)
- P Pongprueksa
- Pong Pongprueksa, DDS, MSc, PhD candidate, KU Leuven – BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Belgium and Department of Operative Dentistry and Endodontics, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - V Miletic
- Vesna Miletic, BDS, MSc, PhD, KU Leuven – BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Belgium and University of Belgrade, School of Dental Medicine, Belgrade, Serbia
| | - J De Munck
- Jan De Munck, DDS, PhD, KU Leuven – BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Belgium
| | - NR Brooks
- Neil R. Brooks, BSc(Hons), PhD, Department of Chemistry, KU Leuven (University of Leuven), Leuven, Belgium
| | - F Meersman
- Filip Meersman, MSci, PhD, Department of Chemistry, KU Leuven (University of Leuven), Leuven, Belgium
| | - E Nies
- Erik Nies, MSci, PhD, Department of Chemistry, KU Leuven (University of Leuven), Leuven, Belgium
| | - B Van Meerbeek
- Bart Van Meerbeek, DDS, PhD, KU Leuven – BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Belgium
| | - KL Van Landuyt
- Kirsten L Van Landuyt, DDS, PhD, KU Leuven – BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Belgium
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Peumans M, De Munck J, Mine A, Van Meerbeek B. Clinical effectiveness of contemporary adhesives for the restoration of non-carious cervical lesions. A systematic review. Dent Mater 2014; 30:1089-103. [PMID: 25091726 DOI: 10.1016/j.dental.2014.07.007] [Citation(s) in RCA: 160] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 07/06/2014] [Accepted: 07/11/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVES The aim of this systematic review was to evaluate the clinical effectiveness of contemporary adhesives for the restoration of non-carious cervical lesions (NCCLs) in terms of restoration retention as a function of time. METHODS Medline Ovid and IADR abstracts were reviewed for NCCLs clinical trials from 1950 to 2013. The reference list of all eligible trials and relevant review articles was checked to find additional studies. The review did not have any language restrictions. Only randomized controlled clinical trials that evaluated at least two adhesives for a follow-up period of at least 18 months were included. Materials with adhesive potential were categorized into 6 main classes: 3-step etch&rinse adhesives (3E&Ra's), 2-step etch&rinse adhesives (2E&Ra's), 2-step self-etch adhesives (2SEa's), 1-step self-etch adhesives (1SEa's), glass-ionomers (GI's) and self-adhesive composites (SAC's). The first four can bond restorative composite to tooth tissue. Both 2SEa and 1SEa were further sub-divided in 'mild' and 'intermediately strong (1/2SEa_m), with a pH≥1.5, and 'strong' (1/2SEa_s), with a pH<1.5. From the restoration retention rates as a function of time the average annual failure rate (AFR) per adhesive and adhesive class was calculated. RESULTS The lowest AFR scores [mean (SD)] were recorded for GI [2.0 (1.4)] shortly followed by 2SEa_m [2.5 (1.5)], 3E&Ra [3.1 (2)] and 1SEa_m [3.6 (4.3)] (Tukey Contrasts: p>0.05). Significantly higher AFR scores were recorded for 1SEa_s [5.4 (4.8)], 2E&R [5.8 (4.9)], and 2SEa_s [8.4 (7.9)] (p>0.05). In addition, significant differences in AFR were noticed between adhesives of the same class (Kruskal-Wallis sum test: p>0.05), except for GI (p=0.7) and 2SEa_m (p=0.1). Finally, selective enamel etching did not significantly influence the retention rate of SEa (AFR SEa_etch=0.43 (0.49), AFR SEa_non-etch=1.43 (1.77). SIGNIFICANCE The adhesive approach significantly influences the clinical effectiveness of adhesives in NCCLs. Within each class, except for GI, there was a wide variation in clinical bonding effectiveness.
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Affiliation(s)
- M Peumans
- KU Leuven - BIOMAT, Department of Oral Health Sciences, KU Leuven & Dentistry, University Hospitals Leuven, Leuven, Belgium.
| | - J De Munck
- KU Leuven - BIOMAT, Department of Oral Health Sciences, KU Leuven & Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - A Mine
- Department of Fixed Prosthodontics, University Graduate School of Dentistry, Osaka, Japan
| | - B Van Meerbeek
- KU Leuven - BIOMAT, Department of Oral Health Sciences, KU Leuven & Dentistry, University Hospitals Leuven, Leuven, Belgium
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Abstract
Dental zirconia can no longer be considered un-bondable to tooth tissue. In literature, an increasing number of papers indeed report on the bonding effectiveness of different luting techniques to zirconia. We aimed to disclose general trends in bonding to zirconia by systematically collecting zirconia bond-strength data. A search in PubMed and EMBASE revealed 1,371 bond-strength tests reported on in 144 papers. A macro-shear bond-strength protocol was most frequently used; it revealed significantly lower bond strengths and was less discriminative than the other test methods. Regarding luting technique, the combination of mechanical and chemical pre-treatment appeared particularly crucial to obtain durable bonding to zirconia ceramics. The cement choice was not revealed as a determining factor after aging conditions, as long as composite cement was used. Regarding test protocol, a tensile test appeared more discriminative, particularly when combined with ‘water storage’ aging.
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Affiliation(s)
- M. Inokoshi
- KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Kapucijnenvoer 7, blok a bus 7001, B-3000 Leuven, Belgium
| | - J. De Munck
- KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Kapucijnenvoer 7, blok a bus 7001, B-3000 Leuven, Belgium
| | - S. Minakuchi
- Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8549, Japan
| | - B. Van Meerbeek
- KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Kapucijnenvoer 7, blok a bus 7001, B-3000 Leuven, Belgium
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30
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Washino T, Barreto B, Van Ende A, De Munck J, Van Meerbeek B. Micro-tensile bond strength of ‘universal’ adhesives to dentin. Dent Mater 2014. [DOI: 10.1016/j.dental.2014.08.174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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31
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Van Ende A, Barreto B, Lise D, Pyka G, Kerckhofs G, Wevers M, Van Meerbeek B. Fiber orientation in FRC restorations filled in bulk or layers. Dent Mater 2014. [DOI: 10.1016/j.dental.2014.08.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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32
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Yoshihara K, Yoshida Y, Hayakawa S, Nagaoka N, Kamenoue S, Okihara T, Ogawa T, Nakamura M, Osaka A, Van Meerbeek B. Novel fluoro-carbon functional monomer for dental bonding. J Dent Res 2013; 93:189-94. [PMID: 24300311 DOI: 10.1177/0022034513514447] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Among several functional monomers, 10-methacryloxydecyl dihydrogen phosphate (10-MDP) bonded most effectively to hydroxyapatite (HAp). However, more hydrolysis-resistant functional monomers are needed to improve bond durability. Here, we investigated the adhesive potential of the novel fluoro-carbon functional monomer 6-methacryloxy-2,2,3,3,4,4,5,5-octafluorohexyl dihydrogen phosphate (MF8P; Kuraray Noritake Dental Inc., Tokyo, Japan) by studying its molecular interaction with powder HAp using solid-state nuclear magnetic resonance ((1)H MAS NMR) and with dentin using x-ray diffraction (XRD) and by characterizing its interface ultrastructure at dentin using transmission electron microscopy (TEM). We further determined the dissolution rate of the MF8P_Ca salt, the hydrophobicity of MF8P, and the bond strength of an experimental MF8P-based adhesive to dentin. NMR confirmed chemical adsorption of MF8P onto HAp. XRD and TEM revealed MF8P_Ca salt formation and nano-layering at dentin. The MF8P_Ca salt was as stable as that of 10-MDP; MF8P was as hydrophobic as 10-MDP; a significantly higher bond strength was recorded for MF8P than for 10-MDP. In conclusion, MF8P chemically bonded to HAp. Despite its shorter size, MF8P possesses characteristics similar to those of 10-MDP, most likely to be associated with the strong chemical bond between fluorine and carbon. Since favorable bond strength to dentin was recorded, MF8P can be considered a good candidate functional monomer for bonding.
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Affiliation(s)
- K Yoshihara
- KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Belgium
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Feitosa V, Ogliari F, Van Meerbeek B, Watson T, Yoshihara K, Ogliari A, Sinhoreti M, Correr A, Cama G, Sauro S. Can the Hydrophilicity of Functional Monomers Affect Chemical Interaction? J Dent Res 2013; 93:201-6. [DOI: 10.1177/0022034513514587] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The number of carbon atoms and/or ester/polyether groups in spacer chains may influence the interaction of functional monomers with calcium and dentin. The present study assessed the chemical interaction and bond strength of 5 standard-synthesized phosphoric-acid ester functional monomers with different spacer chain characteristics, by atomic absorption spectroscopy (AAS), ATR-FTIR, thin-film x-ray diffraction (TF-XRD), scanning electron microscopy (SEM), and microtensile bond strength (μTBS). The tested functional monomers were 2-MEP (two-carbon spacer chain), 10-MDP (10-carbon), 12-MDDP (12-carbon), MTEP (more hydrophilic polyether spacer chain), and CAP-P (intermediate hydrophilicity ester spacer). The intensity of monomer-calcium salt formation measured by AAS differed in the order of 12-MDDP=10-MDP>CAP-P>MTEP>2-MEP. FTIR and SEM analyses of monomer-treated dentin surfaces showed resistance to rinsing for all monomer-dentin bonds, except with 2-MEP. TF-XRD confirmed the weaker interaction of 2-MEP. Highest µTBS was observed for 12-MDDP and 10-MDP. A shorter spacer chain (2-MEP) of phosphate functional monomers induced formation of unstable monomer-calcium salts, and lower chemical interaction and dentin bond strength. The presence of ester or ether groups within longer spacer carbon chains (CAP-P and MTEP) may affect the hydrophilicity, μTBS, and also the formation of monomer-calcium salts.
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Affiliation(s)
- V.P. Feitosa
- Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
- King’s College London Dental Institute, London, United Kingdom
| | | | | | - T.F. Watson
- King’s College London Dental Institute, London, United Kingdom
| | | | | | - M.A. Sinhoreti
- Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - A.B. Correr
- Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - G. Cama
- King’s College London Dental Institute, London, United Kingdom
| | - S. Sauro
- King’s College London Dental Institute, London, United Kingdom
- CEU Dental Biomaterials, Cardenal Herrera University, Valencia, Spain
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Moretto SG, Russo EMA, Carvalho RCR, De Munck J, Van Landuyt K, Peumans M, Van Meerbeek B, Cardoso MV. 3-year clinical effectiveness of one-step adhesives in non-carious cervical lesions. J Dent 2013; 41:675-82. [PMID: 23747824 DOI: 10.1016/j.jdent.2013.05.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 04/28/2013] [Accepted: 05/29/2013] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVES Despite representing an important component of current dental adhesives, HEMA has been said to negatively influence the long-term stability of adhesion to dentine and enamel. The aim of this randomised clinical trial was to evaluate the 3-year clinical performance of two one-step self-etch adhesives. METHODS Thirty patients had 175 non-carious cervical lesions restored with composite (Gradia Direct Anterior, GC) using either the HEMA-rich adhesive Clearfil Tri-S Bond (C3S; Kuraray) or the HEMA-free adhesive G-Bond (GB; GC). The restorations were evaluated by two examiners at baseline, 6, 12, 24 and 36 months regarding retention, caries recurrence, marginal integrity and discoloration and post-operative sensitivity. The data were statistically analysed with GEE and McNemar tests (p<0.05). RESULTS The recall rate at 6 and 12 months was 100% and decreased to 96.7% at 24 and 36 months. At 3 years, the retention rate was 93.8% for C3S and 98.8% for GB (p=0.14). A pairwise comparison showed no significant differences between the two adhesives for all the parameters evaluated, irrespective of the recall (p>0.05). After 3 years, both adhesives presented an increase in the percentage of clinically acceptable marginal discoloration (C3S: 32.9% and GB: 26.8%) normally associated to clinically acceptable marginal defects (C3S: 35.8% and GB: 26.5%). Only 1 dentine margin of a GB restoration presented a severe marginal defect (1.2%) and 1 C3S restoration presented caries recurrence. The overall 3-year clinical success rate was 92.6% for C3S and 97.6% for GB (p=0.16). CONCLUSION Both one-step self-etch adhesives presented an equally favourable clinical effectiveness at 3 years. CLINICAL SIGNIFICANCE HEMA is a monomer frequently present in dental adhesives in order to increase their wettability and hydrophilicity. However, this monomer negatively influences hydrolytic stability and durability of the adhesive interface complex. In this 3-year clinical trial no significant difference in bonding effectiveness was noticed between a HEMA-rich and HEMA-free one-step adhesive.
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Affiliation(s)
- S G Moretto
- KU Leuven - BIOMAT, Department of Oral Health Sciences, Catholic University of Leuven, Belgium
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Zicari F, Coutinho E, Scotti R, Van Meerbeek B, Naert I. Mechanical properties and micro-morphology of fiber posts. Dent Mater 2013; 29:e45-52. [PMID: 23395426 DOI: 10.1016/j.dental.2012.11.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 11/01/2012] [Indexed: 10/27/2022]
Abstract
OBJECTIVES To evaluate flexural properties of different fiber posts systems and to morphologically characterize their micro-structure. METHODS Six types of translucent fiber posts were selected: RelyX Post (3M ESPE), ParaPost Taper Lux (Colthéne-Whaledent), GC Fiber Post (GC), LuxaPost (DMG), FRC Postec Plus (Ivoclar-Vivadent), D.T. Light-Post (RTD). For each post system and size, ten specimens were subjected to a three-points bending test. Maximum fracture load, flexural strength and flexural modulus were determined using a universal loading device (5848 MicroTester(®), Instron). Besides, for each system, three intact posts of similar dimensions were processed for scanning electron microscopy to morphologically characterize the micro-structure. The following structural characteristics were analyzed: fibers/matrix ratio, density of fibers, diameter of fibers and distribution of fibers. Data were statistically analyzed with ANOVA. RESULTS Type and diameter of posts were found to significantly affect the fracture load, flexural strength and flexural modulus (p<0.05). Regarding maximum fracture load, it was found to increase with post diameter, in each post system (p<0.001). Regarding flexural strength and flexural modulus, the highest values were recorded for posts with the smallest diameter (p<0.001). Finally, structural characteristics significantly varied among the post systems tested. However, any correlation has been found between flexural strength and structural characteristics. SIGNIFICANCE Flexural strength appeared not to be correlated to structural characteristics of fiber posts, but it may rather be affected by mechanical properties of the resin matrix and the interfacial adhesion between fibers and resin matrix.
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Affiliation(s)
- F Zicari
- Leuven BIOMAT Research Cluster, Department of Prosthetic Dentistry, Katholieke Universiteit Leuven, Belgium.
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Zicari F, Van Meerbeek B, Scotti R, Naert I. Effect of ferrule and post placement on fracture resistance of endodontically treated teeth after fatigue loading. J Dent 2012; 41:207-15. [PMID: 23069329 DOI: 10.1016/j.jdent.2012.10.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 06/15/2012] [Accepted: 10/06/2012] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES To evaluate the influence of the ferrule effect (1) and the fibre-post placement (2) on the fracture resistance of endodontically treated teeth subjected to cyclic fatigue loading. METHODS 40 extracted single-rooted upper pre-molars were sectioned at the CEJ (groups a and b) or 2mm above the CEJ (groups c and d), and subsequently endodontically treated. After 24-h water storage at 37°C, specimens were restored according to four build-up approaches (n=10 per group): (a) NF-NP (no ferrule, no post), (b) NF-P (no ferrule, fibre-post), (c) F-NP (ferrule, no post) and (d) F-P (ferrule, fibre post). RelyX Posts (3M-ESPE) were used in groups NF-P and F-P, and were cemented with Panavia F 2.0 (Kuraray). A standardized composite core was built, after which specimens were restored with an all-ceramic crown (IPS Empress CAD, Ivoclar-Vivadent) Specimens were fatigued by exposure to 1,200,000 cycles using a chewing simulator (Willytech). All specimens that survived fatigue loading were fractured using a universal loading device (Micro-Tester, Instron). A two-way analysis of variance was used to determine the statistical significance of the factors ferrule and post on fracture resistance. RESULTS Only one NF-NP specimen failed under fatigue. The ferrule effect significantly enhanced the fracture resistance of the restored teeth, regardless the use of a post (p=0.003). F-NP obtained the highest fracture resistance (758.52±121.89N), which was not significantly different from F-P (647.58±132.95N); NF-NP presented the lowest fracture resistance (361.52±151.69N). For all groups, only 'repairable' failures were recorded. CONCLUSIONS Avoiding extra-removal of sound tooth structure, rather than placing a fibre post, can protect endodontically treated teeth against catastrophic failure. However, when any ferrule can be preserved, a fibre-post may improve the retention and fatigue resistance of the restoration.
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Affiliation(s)
- F Zicari
- Leuven BIOMAT Research Cluster, Department of Prosthetic Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Belgium.
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Yoshida Y, Yoshihara K, Hayakawa S, Nagaoka N, Okihara T, Matsumoto T, Minagi S, Osaka A, Van Landuyt K, Van Meerbeek B. HEMA inhibits interfacial nano-layering of the functional monomer MDP. J Dent Res 2012; 91:1060-5. [PMID: 22968157 DOI: 10.1177/0022034512460396] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Previous research showed that the functional monomer 10-methacryloxydecyl dihydrogen phosphate (MDP) ionically bonds to hydroxyapatite (HAp) and forms a nano-layered structure at the interface with HAp-based substrates. Such hydrophobic nano-layering is considered to contribute to the long-term durability of the bond to tooth tissue. However, dental adhesives are complex mixtures usually containing different monomers. This study investigated the effect of the monomer 2-hydroxyethylmethacrylate (HEMA) on the chemical interaction of MDP with HAp by x-ray diffraction (XRD), nuclear magnetic resonance (NMR), and quartz crystal microbalance (QCM). We examined the chemical interaction of 5 experimental MDP solutions with increasing concentrations of HEMA. XRD revealed that addition of HEMA inhibits nano-layering at the interface, while NMR confirmed that MDP remained adsorbed onto the HAp surface. QCM confirmed this adsorption of MDP to HAp, as well as revealed that the demineralization rate of HAp by MDP was reduced by HEMA. It was concluded that even though the adsorption of MDP to HAp was not hindered, addition of HEMA inhibited interfacial nano-layering. Potential consequences with regard to bond durability necessitate further research.
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Affiliation(s)
- Y Yoshida
- Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8525, Japan.
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Van Ende A, Mine A, De Munck J, Poitevin A, Van Meerbeek B. Bonding of low-shrinking composites in high C-factor cavities. J Dent 2012; 40:295-303. [DOI: 10.1016/j.jdent.2012.01.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 01/04/2012] [Accepted: 01/05/2012] [Indexed: 10/14/2022] Open
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Zicari F, Van Meerbeek B, Scotti R, Naert I. Effect of fibre post length and adhesive strategy on fracture resistance of endodontically treated teeth after fatigue loading. J Dent 2012; 40:312-21. [DOI: 10.1016/j.jdent.2012.01.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 01/10/2012] [Accepted: 01/11/2012] [Indexed: 11/16/2022] Open
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Moretto SG, De Munck J, Wehner M, Freitas PM, Van Meerbeek B. Bonding effectiveness to femtosecond laser-irradiated dentin. Med Oral Patol Oral Cir Bucal 2012. [DOI: 10.4317/medoral.17643507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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De Munck J, Mine A, Poitevin A, Van Ende A, Cardoso MV, Van Landuyt KL, Peumans M, Van Meerbeek B. Meta-analytical review of parameters involved in dentin bonding. J Dent Res 2011; 91:351-7. [PMID: 22173327 DOI: 10.1177/0022034511431251] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Bond-strength testing is the method most used for the assessment of bonding effectiveness to enamel and dentin. We aimed to disclose general trends in adhesive performance by collecting dentin bond-strength data systematically. The PubMed and EMBASE databases were used to identify 2,157 bond-strength tests in 298 papers. Most used was the micro-tensile test, which appeared to have a larger discriminative power than the traditional macro-shear test. Because of the huge variability in dentin bond-strength data and the high number of co-variables, a neural network statistical model was constructed. Variables like 'research group' and 'adhesive brand' appeared most determining. Weighted means derived from this analysis confirmed the high sensitivity of current adhesive approaches (especially of all-in-one adhesives) to long-term water-storage and substrate variability.
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Affiliation(s)
- J De Munck
- Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium.
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42
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Van Landuyt K, Nawrot T, Geebelen B, De Munck J, Snauwaert J, Yoshihara K, Scheers H, Godderis L, Hoet P, Van Meerbeek B. How much do resin-based dental materials release? A meta-analytical approach. Dent Mater 2011; 27:723-47. [DOI: 10.1016/j.dental.2011.05.001] [Citation(s) in RCA: 234] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 02/24/2011] [Accepted: 05/09/2011] [Indexed: 01/10/2023]
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Coutinho E, Cardoso M, Fernandes C, Neves A, Gouvea C, Van Landuyt K, De Munck J, Van Meerbeek B. Nanoleakage Distribution at Adhesive-Dentin Interfaces in 3D. J Dent Res 2011; 90:1019-25. [DOI: 10.1177/0022034511408430] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In spite of its role in the degradation of tooth-biomaterial interfaces, reports on nanoleakage are largely inconsistent. The aim of this work was to assess nanoleakage patterns qualitatively and quantitatively in 3D, to determine the influence of direction, position, and inclination of the field-of-view. Therefore, we applied a gold-standard 3-step etch-and-rinse adhesive to bur-cut dentin surfaces, after which interface samples were sectioned, infiltrated with an ammoniacal silver-nitrate solution, and embedded by common TEM procedures. High-resolution 3D models of interfaces were then generated by FIB and electron tomography, following strict conditions determined by Monte Carlo simulations. Inverted images in FIB tomography disclosed morphological characteristics analogous to those revealed by TEM. Quantitative analysis revealed large variations in silver-nitrate uptake between 2D image projections in different directions. Furthermore, silver-nitrate fractions in individual 2D image projections were seldom related to the total 3D volumetric fraction. Electron tomography showed that inclination also affected the morphology of silver-nitrate patterns. In conclusion, conventional nanoleakage evaluation is heavily influenced by direction, position, and inclination of the field-of-view, and thus may contain artifacts.
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Affiliation(s)
- E. Coutinho
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium, Department of Prosthodontics, School of Dentistry, Fluminense Federal University, Rio de Janeiro, Brazil
| | - M.V. Cardoso
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - C.P. Fernandes
- Department of Prosthodontics, School of Dentistry, Fluminense Federal University, Rio de Janeiro, Brazil
| | - A.A. Neves
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - C.V.D. Gouvea
- Department of Prosthodontics, School of Dentistry, Fluminense Federal University, Rio de Janeiro, Brazil
| | - K.L. Van Landuyt
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - J. De Munck
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - B. Van Meerbeek
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
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Cardoso MV, de Almeida Neves A, Mine A, Coutinho E, Van Landuyt K, De Munck J, Van Meerbeek B. Current aspects on bonding effectiveness and stability in adhesive dentistry. Aust Dent J 2011; 56 Suppl 1:31-44. [PMID: 21564114 DOI: 10.1111/j.1834-7819.2011.01294.x] [Citation(s) in RCA: 201] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- M V Cardoso
- Catholic University of Leuven, School of Dentistry, Oral Pathology and Maxillo-facial Surgery, Department of Conservative Dentistry, Leuven BIOMAT Research Cluster, Leuven, Belgium
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Loomans BAC, Cardoso MV, Opdam NJM, Roeters FJM, De Munck J, Huysmans MCDNJM, Van Meerbeek B. Surface roughness of etched composite resin in light of composite repair. J Dent 2011; 39:499-505. [PMID: 21571031 DOI: 10.1016/j.jdent.2011.04.007] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 04/22/2011] [Accepted: 04/27/2011] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVES In search for clinically effective composite repair protocols, the effect of various etching protocols on the surface roughness of composite resins with different filler composition were investigated. METHODS Of two composite resins (hybrid-filled Clearfil AP-X; nano-filled Filtek Supreme XT) specimens of 3mm thick with a diameter of 7 mm were prepared (n=24). The top surface was polished with 4000-grit SiC-abrasive paper and subjected to one of eight surface treatments: (n=3): negative control (NC), 37% phosphoric acid for 20s (37PA-20s), 3% hydrofluoric acid for 20s (3HF-20s), for 120 s (3HF-120 s), 9.6% hydrofluoric acid for 20s (9.6HF-20s), for 120 s (9.6%HF-120 s), 37PA-20s followed by 9.6%HF for 120 s (37PA-20s/9.6HF-120 s) and 9.6%HF for 120 s followed by 37PA-20s (9.6HF-120s/37PA-20s). Roughness (S(a)) was measured using a 3D noncontact optical interferometer (WYKO) and surface topography imaged by SEM. Multilevel models were used to estimate the variances within a sample and between samples in each group. Using the resulting overall variances and the means for each group, the eight groups were compared consecutively using t-tests (p<0.05). RESULTS The hybrid-filled composite resin demonstrated a significantly rougher surface than the nano-filled (p<0.05). For both composites 9.6%HF-120 s, 37PA-20s/9.6HF-120 s and 9.6%HF-120 s/37PA-20s resulted in a large increase in roughness compared to the other groups (p<0.05). For the hybrid-filled, the succeeding groups (37PA-20s, 3HF-20s, 3HF-120 s and 9.6HF-20s) resulted in a statistically significant increase in surface roughness (p<0.02). For the nano-filled only a statistically significant increase in roughness was found between 3HF-20s and 3HF-120 s (p<0.001) and between 9.6HF-20s and 9.6HF-120 s (p<0.001). SEM surface characterization revealed that the hybrid-filled composite resin was much more affected by etching than the nano-filled. SIGNIFICANCE Composite resins should not be seen as a group of materials having identical properties when it comes to repair. The effect of etching will depend on the composition of the filler particles.
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Affiliation(s)
- B A C Loomans
- College of Dental Science, Department of Preventive and Restorative Dentistry, Radboud University Nijmegen Medical Centre, The Netherlands.
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Yoshihara K, Yoshida Y, Hayakawa S, Nagaoka N, Torii Y, Osaka A, Suzuki K, Minagi S, Van Meerbeek B, Van Landuyt K. Self-etch Monomer-Calcium Salt Deposition on Dentin. J Dent Res 2011; 90:602-6. [DOI: 10.1177/0022034510397197] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- K. Yoshihara
- Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School for Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium
| | - Y. Yoshida
- Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Research Center for Biomedical Engineering, Okayama University, Japan
| | - S. Hayakawa
- Research Center for Biomedical Engineering, Okayama University, Japan
- Biomaterials Laboratory, Graduate School of Natural Science and Technology, Okayama University, Japan
| | - N. Nagaoka
- Laboratory for Electron Microscopy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Y. Torii
- Comprehensive Dental Clinic, Okayama University Hospital, Japan
| | - A. Osaka
- Research Center for Biomedical Engineering, Okayama University, Japan
- Biomaterials Laboratory, Graduate School of Natural Science and Technology, Okayama University, Japan
| | - K. Suzuki
- Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Research Center for Biomedical Engineering, Okayama University, Japan
| | - S. Minagi
- Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - B. Van Meerbeek
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School for Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium
| | - K.L. Van Landuyt
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School for Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium
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Gunst V, Huybrechts B, De Almeida Neves A, Bergmans L, Van Meerbeek B, Lambrechts P. Playing wind instruments as a potential aetiologic cofactor in external cervical resorption: two case reports. Int Endod J 2010; 44:268-82. [DOI: 10.1111/j.1365-2591.2010.01822.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mine A, De Munck J, Cardoso MV, Van Landuyt K, Poitevin A, Kuboki T, Yoshida Y, Suzuki K, Van Meerbeek B. Enamel-Smear Compromises Bonding by Mild Self-Etch Adhesives. J Dent Res 2010; 89:1505-9. [DOI: 10.1177/0022034510384871] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In light of the increased popularity of less acidic, so-called ‘ultra-mild’ self-etch adhesives, adhesion to enamel is becoming more critical. It is hypothesized that this compromised enamel bonding should, to a certain extent, be attributed to interference of bur debris smeared across enamel during cavity preparation. High-resolution transmission electron microscopy revealed that the enamel smear layer differed not only in thickness, but also in crystal density and size, depending on the surface-preparation method used. Lab-demineralization of sections clearly disclosed that resin-infiltration of an ultra-mild self-etch adhesive progressed preferentially along micro-cracks that were abundantly present at and underneath the bur-cut enamel surface. The surface-preparation method significantly affected the nature of the smear layer and the interaction with the ultra-mild adhesive, being more uniform and dense for a lab-SiC-prepared surface vs. a clinically relevant bur-prepared surface.
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Affiliation(s)
- A. Mine
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - J. De Munck
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - M. Vivan Cardoso
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - K.L. Van Landuyt
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - A. Poitevin
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - T. Kuboki
- Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Y. Yoshida
- Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan
| | - K. Suzuki
- Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan
| | - B. Van Meerbeek
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
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Van Landuyt K, De Munck J, Mine A, Cardoso M, Peumans M, Van Meerbeek B. Filler Debonding & Subhybrid-layer Failures in Self-etch Adhesives. J Dent Res 2010; 89:1045-50. [PMID: 20631093 DOI: 10.1177/0022034510375285] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The mechanisms behind bond degradation are still largely unknown, in particular with respect to self-etch adhesives. One-step adhesives have been especially documented with problems, such as insufficient polymerization, water-uptake and subsequent plasticization, water- and enzyme-induced nanoleakage, and/or the presence of voids due to phase-separation or osmosis. It was hypothesized that these shortcomings may weaken the adhesive layer and, as such, may jeopardize long-term bonding. In contrast to the control three-step etch & rinse adhesive, the bond strength to dentin of both one-step and two-step self-etch adhesives decreased after six-month water storage. TEM revealed not only that they exhibited filler de-bonding within the adhesive resin layer, due to hydrolysis of the filler-matrix coupling, but also that they failed predominantly directly under the hybrid layer at dentin, in spite of the presence of interfacial droplets and nanoleakage in the adhesive layer. These failures just under the hybrid layer may be attributed to insufficient encapsulation of surface smear.
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Affiliation(s)
- K.L. Van Landuyt
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - J. De Munck
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - A. Mine
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - M.V. Cardoso
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - M. Peumans
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
| | - B. Van Meerbeek
- Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium
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50
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Loomans B, Mine A, Roeters F, Opdam N, De Munck J, Huysmans M, Van Meerbeek B. Hydrofluoric acid on dentin should be avoided. Dent Mater 2010; 26:643-9. [DOI: 10.1016/j.dental.2010.03.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 12/17/2009] [Accepted: 03/08/2010] [Indexed: 10/19/2022]
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