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Kunrath MF, Giraldo-Osorno PM, Mendes K, Gomes ATPC, Rosa N, Barros M, Dahlin C. Unveiling the consequences of early human saliva contamination on membranes for guided bone regeneration. J Periodontal Res 2024. [PMID: 38644743 DOI: 10.1111/jre.13266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 03/28/2024] [Accepted: 03/29/2024] [Indexed: 04/23/2024]
Abstract
AIMS GBR membranes have various surface properties designed to elicit positive responses in regenerative clinical procedures; dental clinicians attempt to employ techniques to prevent the direct interaction of contaminated oral fluids with these biomaterials. However, saliva is uninterruptedly exhibited in oral surgical procedures applying GBR membranes, suggesting a persistent interaction with biomaterials and the surrounding oral tissues. This fundamental study aimed to investigate potential alterations in the physical, chemical, and key biological properties of membranes for guided bone regeneration (GBR) caused by isolated early interaction with human saliva. METHODS A reproducible step-by-step protocol for collecting and interacting human saliva with membranes was developed. Subsequently, membranes were evaluated for their physicochemical properties, protein quantification, DNA, and 16S rRNA levels viability of two different cell lines at 1 and 7 days, and ALP activity. Non-interacted membranes and pure saliva of donors were applied as controls. RESULTS Qualitative morphological alterations were noticed; DNA extraction and 16S quantification revealed significantly higher values. Furthermore, the viability of HGF-1 and MC3T3-E1 cells was significantly (p < .05) reduced following saliva interaction with biodegradable membranes. Saliva contamination did not prejudice PTFE membranes significantly in any biological assay. CONCLUSIONS These outcomes demonstrated a susceptible response of biodegradable membranes to isolated early human saliva interaction, suggesting impairment of structural morphology, reduced viability to HGF-1 and MC3T3-E1, and higher absorption/adherence of DNA/16S rRNA. As a result, clinical oral procedures may need corresponding refinements.
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Affiliation(s)
- Marcel F Kunrath
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa, Viseu, Portugal
- Dentistry Department, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
| | - Paula Milena Giraldo-Osorno
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
| | - Karina Mendes
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa, Viseu, Portugal
| | - Ana T P C Gomes
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa, Viseu, Portugal
| | - Nuno Rosa
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa, Viseu, Portugal
| | - Marlene Barros
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa, Viseu, Portugal
| | - Christer Dahlin
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
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Riivari S, Areid N, Närvä E, Willberg J, Närhi T. Saliva exposure reduces gingival keratinocyte growth on TiO 2-coated titanium. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2024; 35:25. [PMID: 38635066 PMCID: PMC11026266 DOI: 10.1007/s10856-024-06792-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 03/19/2024] [Indexed: 04/19/2024]
Abstract
Bioactive, nanoporous TiO2-coating has been shown to enhance cell attachment on titanium implant surface. The aim of this study was to evaluate, whether the saliva proteins affect the epithelial cell adhesion on TiO2-coated and non-coated titanium. Grade V titanium discs were polished. Half of the discs were provided with TiO2-coating produced in sol with polycondensation method. Half of the TiO2-coated and non-coated discs were treated with pasteurized saliva for 30 min. After saliva treatment, the total protein amounts on surfaces were measured. Next, the hydrophilicity of discs were measured with water contact angle measurements. Further, the gingival keratinocyte adhesion strength was measured after 2 and 6 h of cultivation using serial trypsinization. In addition, cell growth and proliferation were measured after 1, 3, and 7 days of cell culture. Finally, cell morphology, spreading and adhesion protein signals were detected with high resolution confocal microscopy. As a result, in sol coated TiO2-surface had significantly higher hydrophilicity when compared to non-coated titanium, meanwhile both non-coated and TiO2-coated surfaces with saliva treatment had a significant increase in hydrophilicity. Importantly, the amounts of adhered saliva proteins were equal between TiO2-coated and non-coated surfaces. Adhesion strength against enzymatic detachment was weakest on non-coated titanium after saliva exposure. Cell proliferation and cell spreading were highest on TiO2-coated titanium, but saliva exposure significantly decreased cell proliferation and spreading on TiO2-coated surface. To conclude, even though saliva exposure makes titanium surfaces more hydrophilic, it seems to neutralize the bioactive TiO2-coating and decrease cell attachment to TiO2-coated surface.
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Affiliation(s)
- Sini Riivari
- Department of Prosthetic Dentistry and Stomatognathic Physiology, University of Turku, FI-20520, Turku, Finland.
| | - Nagat Areid
- Department of Prosthetic Dentistry and Stomatognathic Physiology, University of Turku, FI-20520, Turku, Finland
| | - Elisa Närvä
- Institute of Biomedicine and Cancer Research Laboratory FICAN West, University of Turku, FI-20520, Turku, Finland
| | - Jaana Willberg
- Department of Oral Pathology and Oral Radiology, University of Turku, FI-20520, Turku, Finland
- Turku University Hospital and University of Turku, FI-20520, Turku, Finland
| | - Timo Närhi
- Department of Prosthetic Dentistry and Stomatognathic Physiology, University of Turku, FI-20520, Turku, Finland
- Wellbeing Services County of South-West Finland and University of Turku, FI-20520, Turku, Finland
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Kunrath MF, Dahlin C. Does saliva contamination interfere or stimulate regenerative processes applying current biomaterials on oral surgical sites? Br Dent J 2023; 234:305-307. [PMID: 36899235 DOI: 10.1038/s41415-023-5573-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 12/07/2022] [Indexed: 03/12/2023]
Abstract
Innovative dental biomaterials have been developed in order to stimulate higher biocompatibility and faster healing times using responsive surfaces for regenerative procedures. However, saliva is one of the fluids to interact with these biomaterials in the first instance. Studies have revealed significant negative effects on the biomaterials' properties, biocompatibility and bacterial colonisation after saliva contact. Nevertheless, the current literature is unclear about the profound effects of saliva on regenerative procedures. The scientific community urges further detailed studies associating innovative biomaterials/saliva/microbiology/immunology in order to clarify clinical outcomes. This paper discusses and provides information about the challenges of research using human saliva, the lack of standardisation in protocols applying saliva, and tentative applications of saliva proteins associated with innovative dental biomaterials.
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Affiliation(s)
- Marcel F Kunrath
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, PO Box 412, SE 405 30, Göteborg, Sweden; Department of Dentistry, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil.
| | - Christer Dahlin
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, PO Box 412, SE 405 30, Göteborg, Sweden; Department of Oral, Maxillofacial Surgery and Research and Development, NU Hospital Organisation, Trollhättan, Sweden
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Hu H, Burrow MF, Leung WK. Proteomic profile of in situ acquired pellicle on tooth and restorative material surfaces. J Dent 2023; 129:104389. [PMID: 36526084 DOI: 10.1016/j.jdent.2022.104389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/08/2022] [Accepted: 12/10/2022] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVES To evaluate and compare the proteomic profile of acquired pellicle on smooth bovine tooth and tooth-coloured restorative materials, including resin composite (RC), glass ionomer cement (GIC), and casein phosphopeptide-amorphous calcium phosphate modified GIC (CPP-ACP GIC). METHODS Two-hour in situ pellicles on tooth/materials specimens mounted in oral appliances worn by ten healthy adults were investigated. Pellicle proteins and corresponding unstimulated whole saliva were quantitatively analysed through liquid chromatography-tandem mass spectrometry. RESULTS Significantly higher amounts of protein were adsorbed onto tooth surface than restorative materials tested (4.11 ± 0.69 vs. 2.54 ± 0.38/2.98 ± 0.80/3.01 ± 0.37 µg, RC/GIC/CPP-ACP GIC). From the ten participants, 1,444 (487-1,086/person), 1,454 (645-1,051/person), 1,731 (454-1,475/person), or 1,597 (423-1,261/person) pellicle proteins were detected at least once on bovine tooth, RC, GIC, or CPP-ACP GIC, respectively, and with 1,072 (304-793/person) salivary proteins identified. Comparative quantification revealed minor differences between tooth and restorative materials pellicle profiles. High inter-individual variations in pellicle protein composition were demonstrated. Compared to the salivary protein profile, 214/57 proteins showed significantly increased/decreased abundance in pellicle formed on at least one substrate (fold change > 3.325/fold change < 0.301). Gene Ontology enrichment analysis showed some pellicle proteins detected with increased affinity to tooth/material surface were identified as being related to "calcium-dependent protein binding" or "cell-cell adhesion mediator activity". CONCLUSION Similar protein quantity and composition was observed in 2 h in situ pellicles formed on different smooth restorative material surfaces. The proteomic profile of pellicles appeared distinct from that of the corresponding unstimulated whole saliva. CLINICAL SIGNIFICANCE Host backgrounds appeared more influential on the proteomic profile of the in situ acquired pellicle than the underlying substrate characteristics among systemically and orally healthy adults. Pellicle proteins preferentially adsorbed on tooth/materials were putatively associated with calcium ion homeostasis or host-microbiota interaction.
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Affiliation(s)
- Hongying Hu
- Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Sai Ying Pun, Hong Kong SAR, China
| | - Michael Francis Burrow
- Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Sai Ying Pun, Hong Kong SAR, China
| | - Wai Keung Leung
- Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Sai Ying Pun, Hong Kong SAR, China.
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Tang Y, Lei L, Yang D, Zheng J, Zeng Q, Xiao H, Zhou Z. Calcium release-mediated adsorption and lubrication of salivary proteins on resin-based dental composites. J Mech Behav Biomed Mater 2022; 135:105437. [DOI: 10.1016/j.jmbbm.2022.105437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/28/2022] [Accepted: 08/29/2022] [Indexed: 11/29/2022]
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Kunrath MF, Correia A, Teixeira ER, Hubler R, Dahlin C. Superhydrophilic Nanotextured Surfaces for Dental Implants: Influence of Early Saliva Contamination and Wet Storage. NANOMATERIALS 2022; 12:nano12152603. [PMID: 35957034 PMCID: PMC9370139 DOI: 10.3390/nano12152603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/07/2022] [Accepted: 07/27/2022] [Indexed: 12/02/2022]
Abstract
Hydrophilic and nanotextured surfaces for dental implants have been reported as relevant properties for early osseointegration. However, these surface characteristics are quite sensitive to oral interactions. Therefore, this pilot study aimed to investigate the superficial alterations caused on hydrophilic nanotubular surfaces after early human saliva interaction. Titanium disks were treated using an anodization protocol followed by reactive plasma application in order to achieve nanotopography and hydrophilicity, additionally; surfaces were stored in normal atmospheric oxygen or wet conditioning. Following, samples were interacted with saliva for 10 min and analyzed regarding physical–chemical properties and cellular viability. Saliva interaction did not show any significant influence on morphological characteristics, roughness measurements and chemical composition; however, hydrophilicity was statistically altered compromising this feature when the samples were stored in common air. Cellular viability tested with pre-osteoblasts cell line (MC3T3-E1) reduced significantly at 48 h on the samples without wet storage after saliva contamination. The applied wet-storage methodology appears to be effective in maintaining properties such as hydrophilicity during saliva interaction. In conclusion, saliva contamination might impair important properties of hydrophilic nanotubular surfaces when not stored in wet conditions, suggesting the need of saliva-controlled sites for oral application of hydrophilic surfaces and/or the use of modified-package methods associated with their wet storage.
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Affiliation(s)
- Marcel F. Kunrath
- Department of Biomaterials, Institute of Clinical Sciences, The Sahlgrenska Academy at University of Gothenburg, P.O. Box 412, SE 405 30 Göteborg, Sweden
- Department of Dentistry, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre 90619-900, Brazil;
- Materials and Nanoscience Laboratory, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre 90619-900, Brazil;
- Correspondence: (M.F.K.); (C.D.); Tel.: +46-0722063757 (M.F.K.)
| | - André Correia
- Universidade Católica Portuguesa, Faculty of Dental Medicine, Centre for Interdisciplinary Research in Health, 3504-505 Viseu, Portugal;
| | - Eduardo R. Teixeira
- Department of Dentistry, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre 90619-900, Brazil;
| | - Roberto Hubler
- Materials and Nanoscience Laboratory, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre 90619-900, Brazil;
| | - Christer Dahlin
- Department of Biomaterials, Institute of Clinical Sciences, The Sahlgrenska Academy at University of Gothenburg, P.O. Box 412, SE 405 30 Göteborg, Sweden
- Correspondence: (M.F.K.); (C.D.); Tel.: +46-0722063757 (M.F.K.)
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Kunrath MF, Dahlin C. The Impact of Early Saliva Interaction on Dental Implants and Biomaterials for Oral Regeneration: An Overview. Int J Mol Sci 2022; 23:2024. [PMID: 35216139 PMCID: PMC8875286 DOI: 10.3390/ijms23042024] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 12/11/2022] Open
Abstract
The presence of saliva in the oral environment is relevant for several essential health processes. However, the noncontrolled early saliva interaction with biomaterials manufactured for oral rehabilitation may generate alterations in the superficial properties causing negative biological outcomes. Therefore, the present review aimed to provide a compilation of all possible physical-chemical-biological changes caused by the early saliva interaction in dental implants and materials for oral regeneration. Dental implants, bone substitutes and membranes in dentistry possess different properties focused on improving the healing process when in contact with oral tissues. The early saliva interaction was shown to impair some positive features present in biomaterials related to quick cellular adhesion and proliferation, such as surface hydrophilicity, cellular viability and antibacterial properties. Moreover, biomaterials that interacted with contaminated saliva containing specific bacteria demonstrated favorable conditions for increased bacterial metabolism. Additionally, the quantity of investigations associating biomaterials with early saliva interaction is still scarce in the current literature and requires clarification to prevent clinical failures. Therefore, clinically, controlling saliva exposure to sites involving the application of biomaterials must be prioritized in order to reduce impairment in important biomaterial properties developed for rapid healing.
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Affiliation(s)
- Marcel Ferreira Kunrath
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, SE 405 30 Goteborg, Sweden;
- Department of Dentistry, School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), P.O. Box 6681, Porto Alegre 90619-900, RS, Brazil
| | - Christer Dahlin
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, SE 405 30 Goteborg, Sweden;
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Fischer NG, Aparicio C. The salivary pellicle on dental biomaterials. Colloids Surf B Biointerfaces 2021; 200:111570. [PMID: 33460965 PMCID: PMC8005451 DOI: 10.1016/j.colsurfb.2021.111570] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/23/2020] [Accepted: 01/07/2021] [Indexed: 12/18/2022]
Abstract
The salivary pellicle, an adlayer formed by adsorption of salivary components on teeth and dental biomaterials, has direct consequences on basic outcomes of dentistry. Here, we provide an overview of salivary pellicle formation processes with a critical focus on dental biomaterials. We describe and critique the array of salivary pellicle measurement techniques. We also discuss factors that may affect salivary pellicle formation and the heterogeneity of the published literature describing salivary pellicle formation on dental biomaterials. Finally, we survey the many effects salivary pellicles have on dental biomaterials and highlight its implications on design criteria for dental biomaterials. Future investigations may lead to rationally designed dental biomaterials to control the salivary pellicle and enhance material function and patient outcomes.
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Affiliation(s)
- Nicholas G Fischer
- MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Conrado Aparicio
- MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, Minnesota, 55455, USA.
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Barberi J, Spriano S. Titanium and Protein Adsorption: An Overview of Mechanisms and Effects of Surface Features. MATERIALS (BASEL, SWITZERLAND) 2021; 14:1590. [PMID: 33805137 PMCID: PMC8037091 DOI: 10.3390/ma14071590] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/09/2021] [Accepted: 03/19/2021] [Indexed: 12/14/2022]
Abstract
Titanium and its alloys, specially Ti6Al4V, are among the most employed materials in orthopedic and dental implants. Cells response and osseointegration of implant devices are strongly dependent on the body-biomaterial interface zone. This interface is mainly defined by proteins: They adsorb immediately after implantation from blood and biological fluids, forming a layer on implant surfaces. Therefore, it is of utmost importance to understand which features of biomaterials surfaces influence formation of the protein layer and how to guide it. In this paper, relevant literature of the last 15 years about protein adsorption on titanium-based materials is reviewed. How the surface characteristics affect protein adsorption is investigated, aiming to provide an as comprehensive a picture as possible of adsorption mechanisms and type of chemical bonding with the surface, as well as of the characterization techniques effectively applied to model and real implant surfaces. Surface free energy, charge, microroughness, and hydroxylation degree have been found to be the main surface parameters to affect the amount of adsorbed proteins. On the other hand, the conformation of adsorbed proteins is mainly dictated by the protein structure, surface topography at the nano-scale, and exposed functional groups. Protein adsorption on titanium surfaces still needs further clarification, in particular concerning adsorption from complex protein solutions. In addition, characterization techniques to investigate and compare the different aspects of protein adsorption on different surfaces (in terms of roughness and chemistry) shall be developed.
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Affiliation(s)
- Jacopo Barberi
- Department of Applied Science and Technology, Politecnico di Torino, 10129 Turin, Italy;
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Shlyapnikov YM, Malakhova EA, Shlyapnikova EA. Improving Immunoassay Performance with Cleavable Blocking of Microarrays. Anal Chem 2021; 93:1126-1134. [PMID: 33305941 DOI: 10.1021/acs.analchem.0c04175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Among the key issues that are commonly associated with the development of microarray-based assays are nonspecific binding and diffusion constraints. Here we present a novel strategy addressing both of these challenges simultaneously. The essence of the method consists in blocking the microarray surface with a blocking agent containing a perfluoroalkyl chain and a disulfide linker. The resulting surface is hydrophobic, and no immiscible liquid layer remains on it upon cyclically draining and replenishing the sample solution, ensuring an efficient mass transfer of an analyte onto a microarray. Prior to the signal detection procedure, disulfide bonds are chemically cleaved, and the perfluoroalkyl chains are removed from the microarray surface along with nonspecifically adsorbed proteins, resulting in extremely low background. Using conventional fluorescent detection, we show a 30-fold increase in signal/background ratio compared to a common epoxy-modified glass substrate. The combination of this technique with magnetic beads detection results in a simple and ultrasensitive cholera toxin (CT) immunoassay. The limit of detection (LOD) is 1 fM, which is achieved with an analyte binding time of 1 h. Efficient mass transfer provides highly sensitive detection of whole virus particles despite their low diffusion coefficient. The achieved LOD for vaccinia virus is 104 particles in 1 mL of sample. Finally, we have performed for the first time the simultaneous detection of whole virus and CT protein biomarker in a single assay. The developed technique can be used for multiplex detection of trace amounts of pathogens of various natures.
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Affiliation(s)
- Yuri M Shlyapnikov
- Institute of Theoretical and Experimental Biophysics Russian Academy of Sciences, Pushchino 142290, Russia
| | - Ekaterina A Malakhova
- Institute of Theoretical and Experimental Biophysics Russian Academy of Sciences, Pushchino 142290, Russia
| | - Elena A Shlyapnikova
- Institute of Theoretical and Experimental Biophysics Russian Academy of Sciences, Pushchino 142290, Russia
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Wang Y, Lam ATW. Inhibitory effects of saliva as a suspending fluid on attachment of oral bacteria to hydroxyapatite and titanium. Arch Oral Biol 2020; 120:104924. [PMID: 33091662 DOI: 10.1016/j.archoralbio.2020.104924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/22/2020] [Accepted: 09/25/2020] [Indexed: 12/18/2022]
Abstract
OBJECTIVES This study aims to examine the influence of saliva on the attachment of oral bacteria to hydroxyapatite and titanium surfaces in an in vitro setting using saliva as a suspending fluid for the bacterial cells, and to investigate the changes in bacterial surface physicochemical properties (hydrophobicity and charge) induced by saliva. DESIGN Saliva collected from human donors was used to treat five strains of oral bacteria. The surface hydrophobicity and charge of the treated cells were measured. The effects of saliva as a suspending fluid on attachment of the strains to hydroxyapatite and titanium were investigated. RESULTS Saliva was found to inhibit the attachment of four streptococcal strains by up to 100-fold. The inhibitory effects were potentially due to changes in cell-surface physicochemical properties induced by saliva. These effects were, however, not observed on Actinomyces naeslundii. CONCLUSIONS The results suggest that saliva may reduce bacterial colonization by oral streptococci and that using saliva as a suspending fluid may be a useful addition for bacterial attachment studies.
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Affiliation(s)
- Yi Wang
- School of Dentistry, the University of Queensland, 288 Herston Road, Herston, Brisbane, Queensland 4006, Australia.
| | - Antonia T W Lam
- School of Dentistry, the University of Queensland, 288 Herston Road, Herston, Brisbane, Queensland 4006, Australia
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Sang T, Ye Z, Fischer NG, Skoe EP, Echeverría C, Wu J, Aparicio C. Physical-chemical interactions between dental materials surface, salivary pellicle and Streptococcus gordonii. Colloids Surf B Biointerfaces 2020; 190:110938. [PMID: 32172164 DOI: 10.1016/j.colsurfb.2020.110938] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/03/2020] [Accepted: 03/02/2020] [Indexed: 11/18/2022]
Abstract
Dental materials are susceptible to dental plaque formation, which increases the risk of biofilm-associated oral diseases. Physical-chemical properties of dental material surfaces can affect salivary pellicle formation and bacteria attachment, but relationships between these properties have been understudied. We aimed to assess the effects of surface properties and adsorbed salivary pellicle on Streptococcus gordonii adhesion to traditional dental materials. Adsorption of salivary pellicle from one donor on gold, stainless steel, alumina and zirconia was monitored with a quartz crystal microbalance with dissipation monitoring (QCM-D). Surfaces were characterized by X-ray photoelectron spectroscopy, atomic force microscopy and water contact angles measurement before and after pellicle adsorption. Visualization and quantification of Live/Dead stained bacteria and scanning electron microscopy were used to study S. gordonii attachment to materials with and without pellicle. The work of adhesion between surfaces and bacteria was also determined. Adsorption kinetics and the final thickness of pellicle formed on the four materials were similar. Pellicle deposition on all materials increased surface hydrophilicity, surface energy and work of adhesion with bacteria. Surfaces with pellicle had significantly more attached bacteria than surfaces without pellicle, but the physical-chemical properties of the dental material did not significantly alter bacteria attachment. Our findings suggested that the critical factor increasing S. gordonii attachment was the salivary pellicle formed on dental materials. This is attributed to increased work of adhesion between bacteria and substrates with pellicle. New dental materials should be designed for controlling bacteria attachment by tuning thickness, composition and structure of the adsorbed salivary pellicle.
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Affiliation(s)
- Ting Sang
- The Affiliated Stomatological Hospital of Nanchang University & The Key Laboratory of Oral Biomedicine, Nanchang, Jiangxi Province, 330006, China; MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Zhou Ye
- MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Nicholas G Fischer
- MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Erik P Skoe
- MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Constanza Echeverría
- MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, MN, 55455, USA; Cariology Unit, Department of Oral Rehabilitation, University of Talca, Talca, 3460000, Chile
| | - Jun Wu
- The Affiliated Stomatological Hospital of Nanchang University & The Key Laboratory of Oral Biomedicine, Nanchang, Jiangxi Province, 330006, China.
| | - Conrado Aparicio
- MDRCBB, Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, MN, 55455, USA.
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Gvetadze RS, Dmitrieva NA, Voronin AN. [Adhesion of microorganisms to various dental materials used to form a gum contour in implant-retained restorations]. STOMATOLOGII︠A︡ 2019; 98:118-123. [PMID: 31701941 DOI: 10.17116/stomat201998051118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The article the literature review on dental materials for the manufacture of gum formers used in dental implantology. Adhesion of microorganisms to titanium, PMMA and PEEK resins is discussed. According to published studies PEEK polymer is characterized by a similar bacterial contamination compared to titanium but shows lower degree of contamination when compared to acrylic resins in equal conditions.
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Affiliation(s)
- R Sh Gvetadze
- Central Research Institute of Dentistry and Maxillofacial Surgery, Moscow, Russia
| | - N A Dmitrieva
- Central Research Institute of Dentistry and Maxillofacial Surgery, Moscow, Russia
| | - A N Voronin
- Central Research Institute of Dentistry and Maxillofacial Surgery, Moscow, Russia
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Fujioka-Kobayashi M, Miron RJ, Lussi A, Gruber R, Ilie N, Price RB, Schmalz G. Effect of the degree of conversion of resin-based composites on cytotoxicity, cell attachment, and gene expression. Dent Mater 2019; 35:1173-1193. [DOI: 10.1016/j.dental.2019.05.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 05/14/2019] [Indexed: 01/13/2023]
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Nogueira RD, Silva CB, Lepri CP, Palma-Dibb RG, Geraldo-Martins VR. Evaluation of Surface Roughness and Bacterial Adhesion on Tooth Enamel Irradiated With High Intensity Lasers. Braz Dent J 2018; 28:24-29. [PMID: 28301014 DOI: 10.1590/0103-6440201701190] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 11/01/2016] [Indexed: 11/21/2022] Open
Abstract
The aim was to evaluate the surface roughness and bacterial adhesion on enamel irradiated with high intensity lasers, associated or not to a fluoride varnish. Eighty fragments of bovine enamel were equally divided in 8 groups (n=10). Group 1 was not treated and Group 2 received only a 5% fluoride varnish application. The other groups were irradiated with an Er:Cr:YSGG (8.92 J/cm2), an Nd:YAG (84.9 J/cm2) and a diode laser (199.04 J/cm2), associated or not to a 5% fluoride varnish. The surface roughness was measured before and after treatments. Afterward, all samples were incubated in a suspension of S. mutans at 37 °C for 24 h. The colony-forming units (CFU) were counted by a stereoscope and the results were expressed in CFU/mm2. One-way ANOVA and the Tukey´s test compared the roughness data and the Student´s test compared the results obtained in the bacterial adhesion test (a=5%). The results showed that the irradiated samples without varnish presented the same roughness and the same bacterial adhesion that the non-irradiated samples. However, samples irradiated in the presence of fluoride varnish showed higher surface roughness and higher bacterial adhesion than the non-irradiated samples and those irradiated without varnish. Presence of pigments in the varnish increased the lasers' action on the enamel surface, which produced ablation in this hard tissue and significantly increased its surface roughness. For this reason, the enamel's susceptibility to bacterial adhesion was higher when the irradiation of the samples was made in presence of fluoride varnish.
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Affiliation(s)
- Ruchele D Nogueira
- Biopathology Division, Dental School, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil
| | - Camilla B Silva
- Biopathology Division, Dental School, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil
| | - Cesar P Lepri
- Clinical Dentistry, Dental School, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil
| | - Regina Guenka Palma-Dibb
- Department of Restorative Dentistry, Ribeirão Preto Dental School, USP - Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Biodegradation Studies of Novel Fluorinated Di-Vinyl Urethane Monomers and Interaction of Biological Elements with Their Polymerized Films. Polymers (Basel) 2017; 9:polym9080365. [PMID: 30971044 PMCID: PMC6418586 DOI: 10.3390/polym9080365] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/01/2017] [Accepted: 08/11/2017] [Indexed: 11/16/2022] Open
Abstract
The monomeric components of resin composites in dental restorative materials are susceptible to hydrolysis in the oral cavity. The main objective of this study was to assess the bio-stability of fluorinated urethane dimethacrylates and determine the nature of fluoro-chemistry interactions with protein and bacterial adhesion (both sources of hydrolytic activity) onto cured resin. Degradation studies were performed in the presence of either albumin (in a mildly alkaline pH) or cholesterol esterase (CE). The surface chemistry of the polymers was assessed by water contact angle measurements, pre- and post- incubation with albumin. Adhesion of Streptococcus mutans to cured resin was investigated. The fluorinated monomers were more stable against degradation when compared to the commercial monomer bisphenol A-diglycidyl methacrylate (BisGMA). While fluorinated monomers showed hydrolytic stability with respect to CE, all fluorinated monomers underwent some degree of degradation with albumin. The fluoro-chemistry did not reduce protein and/or bacterial adhesion onto the surface, however post incubation with albumin, the fluorinated surfaces still presented hydrophobic character as determined by the high contact angle values ranging from 79° to 86°. These monomers could potentially be used to increase the hydrophobicity of polymeric composites and provide a means to moderate esterolytic degradation associated with the monomeric component of the polymers within the oral cavity.
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Ebersole JL, Dawson D, Emecen-Huja P, Nagarajan R, Howard K, Grady ME, Thompson K, Peyyala R, Al-Attar A, Lethbridge K, Kirakodu S, Gonzalez OA. The periodontal war: microbes and immunity. Periodontol 2000 2017; 75:52-115. [DOI: 10.1111/prd.12222] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Weber F, Barrantes A. Real-time formation of salivary films onto polymeric materials for dental applications: Differences between unstimulated and stimulated saliva. Colloids Surf B Biointerfaces 2017; 154:203-209. [PMID: 28343118 DOI: 10.1016/j.colsurfb.2017.03.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 02/01/2017] [Accepted: 03/07/2017] [Indexed: 10/20/2022]
Abstract
The formation of salivary films onto oral prostheses materials is of central importance for understanding their performance and interaction with oral tissue and flora. The aim of this work was to study and compare the salivary films formed from unstimulated and stimulated whole saliva on two common polymeric materials, polycarbonate and poly(methyl methacrylate). Irradiating these materials with UV light is a simple way to modify their wettability, roughness and ζ-potential. Therefore, the effect of UV exposure of polycarbonate and poly(methyl methacrylate) on saliva adsorption was also investigated. For this purpose a quartz crystal microbalance with dissipation and SDS-PAGE have been combined in order to associate the thicknesses and viscoelastic properties of the salivary films with their protein composition. SDS-PAGE results suggest that a larger diversity of proteins is involved in the formation of stimulated saliva pellicles. Furthermore, according to QCM-D, pellicles formed from stimulated saliva are thinner and stiffer than the ones formed from unstimulated saliva if the polymeric materials have not been exposed to UV light although both types of saliva form a biphasic layer. For UV-treated materials, the same is applied to polycarbonate but not to poly(methyl methacrylate) where stimulated saliva yields thicker and softer films than unstimulated saliva being the adsorption process of a multiphasic nature. These results highlight the importance of choosing the appropriate sample depending on the type of study to be performed.
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Affiliation(s)
- Florian Weber
- Department of Biomaterials, Institute of Clinical Dentistry, University of Oslo, P.O. box 1109 Blindern, 0317 Oslo, Norway; Technical University of Munich, Munich, Germany.
| | - Alejandro Barrantes
- Department of Biomaterials, Institute of Clinical Dentistry, University of Oslo, P.O. box 1109 Blindern, 0317 Oslo, Norway.
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Schmalz G, Galler KM. Biocompatibility of biomaterials – Lessons learned and considerations for the design of novel materials. Dent Mater 2017; 33:382-393. [DOI: 10.1016/j.dental.2017.01.011] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 01/31/2017] [Indexed: 12/14/2022]
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20
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Cataldi A, Gallorini M, Di Giulio M, Guarnieri S, Mariggiò MA, Traini T, Di Pietro R, Cellini L, Marsich E, Sancilio S. Adhesion of human gingival fibroblasts/Streptococcus mitis co-culture on the nanocomposite system Chitlac-nAg. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2016; 27:88. [PMID: 26970770 PMCID: PMC4789204 DOI: 10.1007/s10856-016-5701-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 02/29/2016] [Indexed: 02/05/2023]
Abstract
Composite materials are increasingly used as dental restoration. In the field of biomaterials, infections remain the main reason of dental devices failure. Silver, in the form of nanoparticles (AgNPs), ions and salt, well known for its antimicrobial properties, is used in several medical applications in order to avoid bacterial infection. To reduce both bacterial adhesion to dental devices and cytotoxicity against eukaryotic cells, we coated BisGMA/TEGDMA methacrylic thermosets with a new material, Chitlac-nAg, formed by stabilized AgNPs with a polyelectrolyte solution containing Chitlac. Here we analyzed the proliferative and adhesive ability of human gingival fibroblasts (HGFs) on BisGMA/TEGDMA thermosets uncoated and coated with AgNPs in a coculture model system with Streptococcus mitis. After 48 h, HGFs well adhered onto both surfaces, while S. mitis cytotoxic response was higher in the presence of AgNPs coated thermosets. After 24 h thermosets coated with Chitlac as well as those coated with Chitlac-nAg exerted a minimal cytotoxic effect on HGFs, while after 48 h LDH release raised up to 20 %. Moreover the presence of S. mitis reduced this release mainly when HGFs adhered to Chitlac-nAg coated thermosets. The reduced secretion of collagen type I was significant in the presence of both surfaces with the co-culture system even more when saliva is added. Integrin β1 localized closely to cell membranes onto Chitlac-nAg thermosets and PKCα translocated into nuclei. These data confirm that Chitlac-nAg have a promising utilization in the field of restorative dentistry exerting their antimicrobial activity due to AgNPs without cytotoxicity for eukaryotic cells.
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Affiliation(s)
- Amelia Cataldi
- Department of Pharmacy, G. d'Annunzio University, Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy
| | - Marialucia Gallorini
- Department of Pharmacy, G. d'Annunzio University, Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy.
| | - Mara Di Giulio
- Department of Pharmacy, G. d'Annunzio University, Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy
| | - Simone Guarnieri
- Center for Aging Science (Ce.S.I.), G. d'Annunzio University Foundation, Chieti, Italy
- Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, Chieti-Pescara, Chieti, Italy
| | - Maria Addolorata Mariggiò
- Center for Aging Science (Ce.S.I.), G. d'Annunzio University Foundation, Chieti, Italy
- Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, Chieti-Pescara, Chieti, Italy
| | - Tonino Traini
- Department of Medical, Oral and Biotechnological Sciences, G. d'Annunzio University, Chieti-Pescara, Chieti, Italy
| | - Roberta Di Pietro
- Department of Medicine and Ageing Sciences, G. d'Annunzio University, Chieti-Pescara, Chieti, Italy
| | - Luigina Cellini
- Department of Pharmacy, G. d'Annunzio University, Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy
| | - Eleonora Marsich
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy
| | - Silvia Sancilio
- Department of Pharmacy, G. d'Annunzio University, Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy
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Nedeljkovic I, Teughels W, De Munck J, Van Meerbeek B, Van Landuyt KL. Is secondary caries with composites a material-based problem? Dent Mater 2015; 31:e247-77. [DOI: 10.1016/j.dental.2015.09.001] [Citation(s) in RCA: 139] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 03/28/2015] [Accepted: 09/01/2015] [Indexed: 12/22/2022]
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22
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Narendrakumar K, Kulkarni M, Addison O, Mazare A, Junkar I, Schmuki P, Sammons R, Iglič A. Adherence of oral streptococci to nanostructured titanium surfaces. Dent Mater 2015; 31:1460-8. [PMID: 26467718 DOI: 10.1016/j.dental.2015.09.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Revised: 07/15/2015] [Accepted: 09/21/2015] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Peri-implantitis and peri-mucositis pose a severe threat to the success of dental implants. Current research focuses on the development of surfaces that inhibit biofilm formation while not inferring with tissue integration. This study compared the adherence of two oral bacterial species, Streptococcus sanguinis and Streptococcus mutans to nanostructured titanium surfaces. METHODS The samples included TiO2 nanotubes formed by anodization of titanium foil of 100, 50 and 15nm diameter (NT15, NT50, NT100), a nanoporous (15nm pore diameter) surface and compact TiO2 control. Adherent surviving bacteria were enumerated after 1h in an artificial saliva medium containing bovine mucin. RESULTS Lowest numbers of adherent bacteria of both species were recovered from the original titanium foil and nanoporous surface and highest numbers from the Ti100 nanotubes. Numbers of attached S. sanguinis increased in the order (NT15<NT50<NT100), correlated with increasing percentage of surface fluoride. The lowest adhesion of S. sanguinis and S. mutans on TiO2 nanostructured surfaces was observed for small diameter nanoporous surfaces which coincides with the highest osteoblast adhesion on small diameter nanotubular/nanoporous surfaces shown in previous work. SIGNIFICANCE This study indicates that the adherence of oral streptococci can be modified by titanium anodization and nanotube diameter.
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Affiliation(s)
- Krunal Narendrakumar
- School of Dentistry, University of Birmingham, St Chad's Queensway, Birmingham B4 6NN, UK
| | - Mukta Kulkarni
- Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana SI-1000, Slovenia
| | - Owen Addison
- School of Dentistry, University of Birmingham, St Chad's Queensway, Birmingham B4 6NN, UK
| | - Anca Mazare
- Department of Materials Science and Engineering, Chair of Surface Science and Corrosion, University of Erlangen-Nuremberg, WW4-LKO, Erlangen, Germany
| | - Ita Junkar
- Jožef Stefan Institute, Jamova cesta 39, Ljubljana SI-1000, Slovenia
| | - Patrik Schmuki
- Department of Materials Science and Engineering, Chair of Surface Science and Corrosion, University of Erlangen-Nuremberg, WW4-LKO, Erlangen, Germany
| | - Rachel Sammons
- School of Dentistry, University of Birmingham, St Chad's Queensway, Birmingham B4 6NN, UK.
| | - Aleš Iglič
- Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana SI-1000, Slovenia
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Holmes A, Rodrigues E, van der Wielen P, Lyons K, Haigh B, Wheeler T, Dawes P, Cannon R. Adherence ofCandida albicansto silicone is promoted by the human salivary protein SPLUNC2/PSP/BPIFA2. Mol Oral Microbiol 2014; 29:90-8. [DOI: 10.1111/omi.12048] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2014] [Indexed: 11/28/2022]
Affiliation(s)
- A.R. Holmes
- Sir John Walsh Research Institute; School of Dentistry; University of Otago; Dunedin New Zealand
| | - E. Rodrigues
- Sir John Walsh Research Institute; School of Dentistry; University of Otago; Dunedin New Zealand
| | - P. van der Wielen
- Sir John Walsh Research Institute; School of Dentistry; University of Otago; Dunedin New Zealand
| | - K.M. Lyons
- Sir John Walsh Research Institute; School of Dentistry; University of Otago; Dunedin New Zealand
| | - B.J. Haigh
- AgResearch Ltd; Ruakura Research Centre; Hamilton New Zealand
| | - T.T. Wheeler
- AgResearch Ltd; Ruakura Research Centre; Hamilton New Zealand
| | - P.J.D. Dawes
- Department of Surgical Sciences; Dunedin School of Medicine; University of Otago; Dunedin New Zealand
| | - R.D. Cannon
- Sir John Walsh Research Institute; School of Dentistry; University of Otago; Dunedin New Zealand
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