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Physical, Mechanical, and Adhesive Properties of Novel Self-Adhesive Resin Cement. Int J Dent 2022; 2022:4475394. [PMID: 35432543 PMCID: PMC9012638 DOI: 10.1155/2022/4475394] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 03/02/2022] [Accepted: 03/03/2022] [Indexed: 11/29/2022] Open
Abstract
Objective To evaluate a newly developed self-adhesive resin cement on physical, mechanical, and adhesive properties and compare it with other commercial self-adhesive resin cements. Materials and Methods Experimental self-adhesive resin cement (SARC) was formulated by our proprietary adhesive resin and filler technology. Maxcem Elite, RelyX Unicem 2, SpeedCem Plus, SmartCEM 2, and Calibra Universal 2 were selected for comparison. Working and setting times, film thickness, water sorption and solubility, flexural strength, and modulus were measured in accordance with ISO-4049. Consistency was tested according to modified ISO 4823. Shear bond strengths were conducted according to ISO 29022. The data were analyzed by one-way ANOVA and post hoc Tukey's tests (p ≤ 0.05). Results All cements showed about 2–4 min working time and about 3–6 min setting time except that RelyX Unicem 2 has a longer working time (9'58”) and setting time (10'18”). All cements meet ISO standards for film thickness (≤50 µm), water sorption (≤40 µg/mm3) except Maxcem Elite (46.19 µg/mm3), and water solubility (≤7.5 µg/mm3) except SmartCEM 2 (11.35 µg/mm3) and Calibra Universal (9.87 µg/mm3). Experimental SARC showed significantly higher flexural strength and modulus than other cements (p < 0.001). For self-curing, Experimental SARC has statistically higher bond strength than other cements (p < 0.001) except statistically the same as RelyX Unicem 2 (p > 0.05). For light-curing, Experimental SARC showed significantly higher bond strength than other cements (p < 0.001) except statistically the same as Maxcem Elite and RelyX Unicem 2 (p > 0.05). For dual-curing, the bond strength of Experimental SARC is significantly higher than that of other cements (p < 0.001). Conclusion The newly developed self-adhesive resin cement exhibited favorable bonding capability and physical and mechanical properties compared to other commercial self-adhesive resin cements and is a good option for cementation of indirect restorations with potential long-term clinical success.
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Santi MR, Lins RBE, Sahadi BO, Denucci GC, Soffner G, Martins LRM. Influence of inorganic composition and filler particle morphology on the mechanical properties of self-adhesive resin cements. Restor Dent Endod 2022; 47:e32. [PMID: 36090509 PMCID: PMC9436654 DOI: 10.5395/rde.2022.47.e32] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 02/22/2022] [Accepted: 03/03/2022] [Indexed: 12/04/2022] Open
Abstract
Objectives This study aimed to evaluate the influence of inorganic composition and filler particle morphology on the mechanical properties of different self-adhesive resin cements (SARCs). Materials and Methods Three SARCs including RelyX Unicem-2 (RUN), Maxcem Elite (MAX), and Calibra Universal (CAL) were tested. Rectangular bar-shaped specimens were prepared for flexural strength (FS) and flexural modulus (FM) and determined by a 3-point bending test. The Knoop microhardness (KHN) and top/bottom microhardness ratio (%KHN) were conducted on the top and bottom faces of disc-shaped samples. Sorption (Wsp) and solubility (Wsl) were evaluated after 24 hours of water immersion. Filler morphology was analyzed by scanning electron microscopy and X-ray energy dispersive spectroscopy (EDS). FS, FM, %KHN, Wsp, Wsl, and EDS results were submitted to 1-way analysis of variance and Tukey’s post-hoc test, and KHN also to paired t-test (α = 0.05). Results SARC-CAL presented the highest FS value, and SARC-RUN presented the highest FM. SARC-MAX and RUN showed the lowest Wsp and Wsl values. KHN values decreased from top to bottom and the SARCs did not differ statistically. Also, all resin cements presented carbon, aluminum, and silica in their composition. SARC-MAX and RUN showed irregular and splintered particles while CAL presented small and regular size particles. Conclusions A higher mechanical strength can be achieved by a reduced spread in grit size and the filler morphology can influence the KHN, as well as photoinitiators in the composition. Wsp and Wsl can be correlated with ions diffusion of inorganic particles.
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Affiliation(s)
- Marina Rodrigues Santi
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil
| | - Rodrigo Barros Esteves Lins
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil
| | - Beatriz Ometto Sahadi
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil
| | - Giovanna Corrêa Denucci
- Department of Cariology, Operative Dentistry and Dental Public Health, Indiana University School of Dentistry, Indianapolis, IN, USA
| | - Gabriela Soffner
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil
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Manso AP, Carvalho RM. Dental Cements for Luting and Bonding Restorations: Self-Adhesive Resin Cements. Dent Clin North Am 2018; 61:821-834. [PMID: 28886770 DOI: 10.1016/j.cden.2017.06.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Self-adhesive resin cements combine easy application of conventional luting materials with improved mechanical properties and bonding capability of resin cements. The presence of functional acidic monomers, dual cure setting mechanism, and fillers capable of neutralizing the initial low pH of the cement are essential elements of the material and should be understood when selecting the ideal luting material for each clinical situation. This article addresses the most relevant aspects of self-adhesive resin cements and their potential impact on clinical performance. Although few clinical studies are available to establish solid clinical evidence, the information presented provides clinical guidance in the dynamic environment of material development.
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Affiliation(s)
- Adriana P Manso
- Department of Oral Biological and Medical Sciences, Division of Biomaterials, Faculty of Dentistry, The University of British Columbia, 368-2199 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Ricardo M Carvalho
- Department of Oral Biological and Medical Sciences, Division of Biomaterials, Faculty of Dentistry, The University of British Columbia, 368-2199 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.
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Sigusch BW, Dietsch S, Berg A, Voelpel A, Guellmar A, Rabe U, Schnabelrauch M, Steen D, Gitter B, Albrecht V, Watts DC, Kranz S. Antimicrobial photodynamic active biomaterials for periodontal regeneration. Dent Mater 2018; 34:1542-1554. [PMID: 29970234 DOI: 10.1016/j.dental.2018.06.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/18/2018] [Accepted: 06/18/2018] [Indexed: 02/09/2023]
Abstract
OBJECTIVE Biomaterials for periodontal regeneration may have insufficient mechanical and antimicrobial properties or are difficult to apply under clinical conditions. The aim of the present study was to develop a polymeric bone grafting material of suitable physical appearance and antimicrobial photodynamic activity. METHODS Two light curable biomaterials based on urethane dimethacrylate (BioM1) and a tri-armed oligoester-urethane methacrylate (BioM2) that additionally contained a mixture of β-tricalcium phosphate microparticles and 20wt% photosensitizer mTHPC (PS) were fabricated and analyzed by their compressive strength, flexural strength and modulus of elasticity. Cytotoxicity was observed by incubating eluates and in direct-contact to MC3T3-E1 cells. Antimicrobial activity was ascertained on Porphyromonas gingivalis and Enterococcus faecalis upon illumination with laser light (652nm, 1×100J/cm2, 2×100J/cm2). RESULTS The compressive strength, flexural strength and elastic modulus were, respectively, 311.73MPa, 22.81MPa and 318.85MPa for BioM1+PS and 742.37MPa, 7.58MPa and 406.23MPa for BioM2+PS. Both materials did not show any cytotoxic behavior. Single laser-illumination (652nm) caused total suppression of P. gingivalis (BioM2+PS), while repeated irradiation reduced E. faecalis by 3.7 (BioM1+PS) and 3.1 (BioM2+PS) log-counts. SIGNIFICANCE Both materials show excellent mechanical and cytocompatible properties. In addition, irradiation with 652nm induced significant bacterial suppression. The manufactured biomaterials might enable a more efficient cure of periodontal bone lesions. Due to the mechanical properties functional stability might be increased. Further, the materials are antimicrobial upon illumination with light that enables a trans-mucosal eradication of residual pathogens.
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Affiliation(s)
- B W Sigusch
- Department of Conservative Dentistry and Periodontology, University Hospitals Jena, An der alten Post 4, 07743 Jena, Germany
| | - S Dietsch
- Department of Conservative Dentistry and Periodontology, University Hospitals Jena, An der alten Post 4, 07743 Jena, Germany
| | - A Berg
- Biomaterials Department, INNOVENT e.V. Pruessingstrasse 27 B, 07745 Jena, Germany
| | - A Voelpel
- Department of Conservative Dentistry and Periodontology, University Hospitals Jena, An der alten Post 4, 07743 Jena, Germany
| | - A Guellmar
- Department of Conservative Dentistry and Periodontology, University Hospitals Jena, An der alten Post 4, 07743 Jena, Germany
| | - U Rabe
- Department of Conservative Dentistry and Periodontology, University Hospitals Jena, An der alten Post 4, 07743 Jena, Germany
| | - M Schnabelrauch
- Biomaterials Department, INNOVENT e.V. Pruessingstrasse 27 B, 07745 Jena, Germany
| | - D Steen
- biolitec research GmbH, Otto-Schott-Str. 15, 07745 Jena, Germany
| | - B Gitter
- biolitec research GmbH, Otto-Schott-Str. 15, 07745 Jena, Germany
| | - V Albrecht
- biolitec research GmbH, Otto-Schott-Str. 15, 07745 Jena, Germany
| | - D C Watts
- University of Manchester, School of Medical Sciences,Oxford Road, M13 9PL Manchester, UK
| | - S Kranz
- Department of Conservative Dentistry and Periodontology, University Hospitals Jena, An der alten Post 4, 07743 Jena, Germany.
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Berlanga Duarte ML, Reyna Medina LA, Reyes PT, González Pérez SE, Herrera González AM. Biobased isosorbide methacrylate monomer as an alternative to bisphenol A glycerolate dimethacrylate for dental restorative applications. J Appl Polym Sci 2016. [DOI: 10.1002/app.44591] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Luis Alberto Reyna Medina
- Centro de Investigación en Química Aplicada; Boulevard Enrique Reyna 140; Saltillo Coahuila 25294 Mexico
| | - Patricia Torres Reyes
- Facultad de Odontología de la Universidad Autónoma de Coahuila; Unidad Saltillo, Avenida Doctora Cuquita Cepeda s/n, Colonia Adolfo López Mateos; Saltillo Coahuila 25125 Mexico
| | - Sergio Emmanuel González Pérez
- Facultad de Odontología de la Universidad Autónoma de Coahuila; Unidad Saltillo, Avenida Doctora Cuquita Cepeda s/n, Colonia Adolfo López Mateos; Saltillo Coahuila 25125 Mexico
| | - Ana María Herrera González
- Área Académica de Ciencias de la Tierra y Materiales, Laboratorio de Polímeros; Universidad Autónoma del Estado de Hidalgo, Carretera Pachuca-Tulancingo Km. 4.5; Colonia Carboneras Mineral de la Reforma Hidalgo 42184 Mexico
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Thompson VP, Watson TF, Marshall GW, Blackman BRK, Stansbury JW, Schadler LS, Pearson RA, Libanori R. Outside-the-(cavity-prep)-box thinking. Adv Dent Res 2013; 25:24-32. [PMID: 24129814 PMCID: PMC3797535 DOI: 10.1177/0022034513502207] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Direct placement restorative materials must interface with tooth structures that are often compromised by caries or trauma. The material must seal the interface while providing sufficient strength and wear resistance to assure function of the tooth for, ideally, the lifetime of the patient. Needed are direct restorative materials that are less technique-sensitive than current resin-based composite systems while having improved properties. The ideal material could be successfully used in areas of the world with limited infrastructure. Advances in our understanding of the interface between the restoration adhesive system and the stages of carious dentin can be used to promote remineralization. Application of fracture mechanics to adhesion at the tooth-restoration interface can provide insights for improvement. Research in polymer systems suggests alternatives to current composite resin matrix systems to overcome technique sensitivity, while advances in nano- and mesoparticle reinforcement and alignment in composite systems can increase material strength, toughness, and wear resistance, foreshadowing dental application.
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Affiliation(s)
- V P Thompson
- Biomaterials, Biomimetics and Biophotonics Group, King's College London Dental Institute, London, UK
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7
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Marghalani HY. Sorption and solubility characteristics of self-adhesive resin cements. Dent Mater 2012; 28:e187-98. [PMID: 22607764 DOI: 10.1016/j.dental.2012.04.037] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2012] [Revised: 04/24/2012] [Accepted: 04/25/2012] [Indexed: 10/28/2022]
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SOMA H, MIYAGAWA Y. Development of metal-resin composite for dental magnet keepers, Part 2: Optimum 4-META content. Dent Mater J 2011; 30:894-7. [DOI: 10.4012/dmj.2011-115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Keskin S, Usanmaz A. Hydroxyl-terminated poly(urethane acrylate) as a soft liner in dental applications: Synthesis and characterization. J Appl Polym Sci 2010. [DOI: 10.1002/app.31972] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Kerby RE, Knobloch LA, Schricker S, Gregg B. Synthesis and evaluation of modified urethane dimethacrylate resins with reduced water sorption and solubility. Dent Mater 2009; 25:302-13. [DOI: 10.1016/j.dental.2008.07.009] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 07/08/2008] [Accepted: 07/17/2008] [Indexed: 10/21/2022]
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Hahnel S, Rosentritt M, Bürgers R, Handel G. Surface properties and in vitro Streptococcus mutans adhesion to dental resin polymers. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2008; 19:2619-2627. [PMID: 18197372 DOI: 10.1007/s10856-007-3352-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 12/21/2007] [Indexed: 05/25/2023]
Abstract
OBJECTIVES This study aimed to characterize the surface properties of experimental resin polymers consisting of monomers differing in functionality and chain length, and to evaluate differences in Streptococcus mutans adhesion. MATERIAL AND METHODS Six resins were prepared (70/30 ratio UDMA/monomer); camphorquinone and ethyl-4-dimethylaminebenzoate were added for light activation. A conventional composite was used as a control. Surface free energy was determined prior and after saliva exposition (2 h, 37 degrees C). After saliva incubation (2 h, 37 degrees C), specimens were incubated with Streptococcus mutans NCTC 10449 for 2.5 h at 37 degrees C. Adherent bacteria were quantified by determining the relative substratum area covered by bacteria using SEM analysis, and by using a fluorometric assay for viable cell quantification. RESULTS No statistically significant differences in total surface free energies were found for uncoated specimens (mean total surface free energies ranging from 39.79 to 49.73 mJ/m(-2)); after saliva coating, statistically significant differences were observed for some of the polymers (mean total surface free energies ranging from 44.13 to 65.81 mJ/m(-2)). Few differences were observed between SEM and fluorescence quantification, finding statistically significant differences in streptococcal adhesion to the experimental polymers. Median bacteria surface coverage ranged from 1.4% for UDMA mixed with 1,10-decandiol dimethacrylate to 16.2% for the control composite material; lowest fluorescence intensities indicating lowest adhesion of bacteria were found for UDMA mixed with 1,10-decandiol dimethacrylate (median 712), and highest values indicating highest adhesion of bacteria were found for UDMA mixed with polyethyleneglycol (600) dimethacrylate (median 11974). CONCLUSION Streptococcus mutans adhesion appears to be different on polymers differing in monomer mixtures, yet correlations between substratum surface free energy and streptococcal adhesion were poor. Further studies are necessary to evaluate additional substratum surface properties and pellicle distribution and composition more thoroughly.
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Affiliation(s)
- Sebastian Hahnel
- Department of Prosthetic Dentistry, Regensburg University Medical Center, Germany.
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12
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Atai M, Ahmadi M, Babanzadeh S, Watts DC. Synthesis, characterization, shrinkage and curing kinetics of a new low-shrinkage urethane dimethacrylate monomer for dental applications. Dent Mater 2007; 23:1030-41. [PMID: 17493674 DOI: 10.1016/j.dental.2007.03.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2007] [Revised: 03/13/2007] [Accepted: 03/14/2007] [Indexed: 11/23/2022]
Abstract
OBJECTIVES The aim of the study was to synthesize and characterize an isophorone-based urethane dimethacrylate (IP-UDMA) resin-monomer and to investigate its shrinkage and curing kinetics. METHODS The IP-UDMA monomer was synthesized through the reaction of polyethylene glycol 400 and isophorone diisocyanate followed by reacting with HEMA to terminate it with methacrylate end groups. The reaction was followed using a standard back titration method and FTIR spectroscopy. The final product was purified and characterized using FTIR, (1)H NMR, elemental analysis and refractive index measurement. The shrinkage-strain of the specimens photopolymerized at circa 700mW/cm(2) was measured using the bonded-disk technique at 23, 35, and 45 degrees C. Initial shrinkage-strain-rates were obtained by numerical differentiation of shrinkage-strain data with respect to time. Degree-of-conversion of the specimens was measured using FTIR spectroscopy. The thermal curing kinetics of the monomer were also studied by differential scanning calorimetry (DSC). RESULTS The characterization methods confirmed the suggested reaction route and the synthesized monomer. A low shrinkage-strain of about 4% was obtained for the new monomer. The results showed that the shrinkage-strain-rate of the monomer followed the autocatalytic model of Kamal and Sourour [Kamal MR, Sourour S. Kinetic and thermal characterization of thermoset cure. Polym Eng Sci 1973;13(1):59-64], which is used to describe the reaction kinetics of thermoset resins. The model parameters were calculated by linearization of the equation. SIGNIFICANCE The model prediction was in a good agreement with the experimental data. The properties of the new monomer compare favorably with properties of the commercially available resins.
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Affiliation(s)
- Mohammad Atai
- Iran Polymer and Petrochemical Institute (IPPI), Tehran, Iran.
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Soma H, Miyagawa Y. Development of Metal-resin Composite for Dental Magnet Keepers. Part 1: Effects of Filler and 4-META Contents on Setting and Flexural Properties. Dent Mater J 2007; 26:129-34. [PMID: 17410903 DOI: 10.4012/dmj.26.129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Nine kinds of experimental soft magnetic resin composites containing SUS447J1 stainless steel particles as filler were prepared. A UDMA/MAA resin with an MAA mole fraction of 0.67 was used as a matrix resin. The effects of three levels of 4-META content and three levels of filler content on the setting and flexural properties were studied. Working time and setting time significantly increased with increase of 4-META and filler contents. Flexural strength significantly increased with increase of 4-META content but with decrease of filler content. Elastic modulus simply increased with increase of both 4-META and filler contents. Although the flexural strength obtained was low, results were considered promising being the first step of this novel development.
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Affiliation(s)
- Hiroko Soma
- Division of Biomaterials, Advanced Research Center, School of Life Dentistry at Niigata, The Nippon Dental University, Niigata 951-8580, Japan.
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Kleinsasser NH, Schmid K, Sassen AW, Harréus UA, Staudenmaier R, Folwaczny M, Glas J, Reichl FX. Cytotoxic and genotoxic effects of resin monomers in human salivary gland tissue and lymphocytes as assessed by the single cell microgel electrophoresis (Comet) assay. Biomaterials 2005; 27:1762-70. [PMID: 16242184 DOI: 10.1016/j.biomaterials.2005.09.023] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Accepted: 09/26/2005] [Indexed: 10/25/2022]
Abstract
Malignant tumors of the three major pairs and the numerous minor salivary glands in humans are rare, and little is known about their various etiologies. Considering the fact that resin monomers from dental restorative materials are released into the saliva and diffuse into the tooth pulp or gingiva, mucosa, and salivary glands, this may potentially contribute to tumorigenesis. Resin monomers may also be reabsorbed and reach the circulating blood as well. Whereas the cytotoxic potential of some components has been clearly documented, data on genotoxicity in human target cells require further investigation. In the present study, genotoxic and cytotoxic effects of three common methacrylates are investigated in human samples of salivary glands and peripheral lymphocytes. The Comet assay was used to quantify DNA single strand breaks, alkali labile and incomplete excision repair sites in salivary gland probes and lymphocytes of 10 volunteers. The xenobiotics investigated were triethyleneglycoldimethacrylate (TEGDMA), urethanedimethacrylate (UDMA), and 2-hydroxyethylmethacrylate (HEMA), with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and dimethyl sulfoxide (DMSO) as controls. DNA migration was analyzed using the tail moment according to Olive (OTM). Cytotoxicity was monitored using trypan blue staining. With TEGDMA concentrations at 10(-5)m (10(-3)m), UDMA at 10(-7)m (10(-7)m), and HEMA at 10(-3)m (10(-5)m) significant enhancements of DNA migration were achieved in tissue cells (lymphocytes) as compared to the negative controls. At higher concentrations of up to 2.5x10(-2)m, induced DNA migration was expressed by OTM at 10.7 for TEGDMA in tissue cells (8.7 in lymphocytes), 10.5 for UDMA (6.4), and 9.7 for HEMA (6.1). The viability of the cell systems was not affected as concerns the threshold level for the assay of 75% viable cells except for the highest concentration tested for TEGDMA and UDMA in tissue cells. At higher concentration levels, all tested substances induced significant enhancement of DNA migration in the Comet assay as a possible sign for genotoxic effects in human salivary glands and lymphocytes. These data add to the results of prior studies in human peripheral lymphocytes and give evidence of a possible risk factor for tumor initiation in human salivary glands.
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Affiliation(s)
- Norbert H Kleinsasser
- Ecogenotoxicology, Department of Otolaryngology--Head and Neck Surgery, University of Regensburg, Franz-Josef-Strauss-Allee 11, D-93042 Regensburg, Germany.
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15
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Kleinsasser NH, Wallner BC, Harréus UA, Kleinjung T, Folwaczny M, Hickel R, Kehe K, Reichl FX. Genotoxicity and cytotoxicity of dental materials in human lymphocytes as assessed by the single cell microgel electrophoresis (comet) assay. J Dent 2004; 32:229-34. [PMID: 15001288 DOI: 10.1016/j.jdent.2003.11.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2003] [Accepted: 11/14/2003] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Resin monomers may be released from restorative dental materials and can diffuse into the tooth pulp or the gingiva, and can reach the saliva and the circulating blood. Whereas the cytotoxic potential of some components has been clearly documented, possible genotoxicity in human target cells demands further investigation. METHODS The Comet assay was used to quantify DNA single strand breaks, alkali labile and incomplete excision repair sites in lymphocytes of 10 volunteers. The xenobiotics investigated were 2-hydroxyethylmethacrylate (HEMA), triethyleneglycoldimethacrylate (TEGDMA), urethane dimethacrylate (UDMA), and bisphenol A-glycidyl methacrylate (Bis-GMA) with N-methyl-N'-nitro-N-nitrosoguanidine and dimethyl sulfoxide as controls. DNA migration was quantified using the tail moment according to Olive (OTM) and DNA migration was considered to be elevated at OTM levels above 2. Cytotoxicity was monitored using trypan blue. RESULTS In the negative controls, OTM ranged between 1.0 and 1.2. With HEMA concentrations above 10(-6)M, TEGDMA 10(-3)M, Bis-GMA 10(-4)M, and UDMA above 10(-6)M relevant enhancements of DNA migration (OTM>2) were achieved. At higher concentrations of up to 2.5x10(-2) induced DNA migration was expressed by OTM of 3.3 for HEMA, 4.5 for TEGDMA, 7.4 for Bis-GMA, and 2.8 for UDMA. Relevant cytotoxic effects were also seen but vitality levels were at a critical range of 71% for Bis-GMA and 73% for TEGDMA, only. SIGNIFICANCE In higher concentration levels, all tested substances induced significant but minor enhancement of DNA migration in the Comet assay as a possible sign for limited genotoxic effects. However, with the highest levels of DNA migration being combined with elevated cytotoxic effects, a low in vivo genotoxic strain appears to be posed by the resin components.
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Affiliation(s)
- Norbert H Kleinsasser
- Klinisch experimentelle Onkologie, Department of Otolaryngology-Head and Neck Surgery, Ludwig-Maximilians-University Munich, Munich, Germany.
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Asaka Y, Miyazaki M, Aboshi H, Yoshida T, Takamizawa T, Kurokawa H, Rikuta A. EDX fluorescence analysis and SEM observations of resin composites. J Oral Sci 2004; 46:143-8. [PMID: 15508746 DOI: 10.2334/josnusd.46.143] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
The purpose of this study was to evaluate the filler compositions of recently available light-cured resins. The composition of each resin paste was evaluated using an energy dispersive X-ray fluorescence spectrometer. Scanning electron microscopic observation of the polymerized resin pastes was also conducted. The main component of each resin composite was Si, while the other elements detected were Al, Ba, Sr, Zr, and K. These elementary compositions differed among the resin pastes used. Three different types of filler morphology were observed; splintered, prepolymerized and splintered, and spherical. The results of this study have thus characterized recently developed resin composites based on their filler elements and morphology.
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Affiliation(s)
- Youhei Asaka
- Nihon University Graduate School of Dentistry, Tokyo, Japan
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