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Machla F, Monou PK, Bekiari C, Andreadis D, Kofidou E, Panteris E, Katsamenis OL, Kokoti M, Koidis P, About I, Fatouros D, Bakopoulou A. Tissue-engineered oral epithelium for dental material testing: towards in vitro biomimetic models. Tissue Eng Part C Methods 2024. [PMID: 39302070 DOI: 10.1089/ten.tec.2024.0154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2024] Open
Abstract
Tissue-engineered oral epithelium (ΤΕΟΕ) was developed after comparing various culture conditions, including submerged- and air-liquid interface (ALI) human cell expansion options. Barrier formation was evaluated via transepithelial electrical resistance (TEER) and calcein permeation via spectrofluorometry. TEOE was further assessed for long-term viability via live/dead staining and development of intercellular connections via transmission electron microscopy (TEM). Tissue architecture was evaluated via histochemistry and the expression of pancytokeratin (pCK) via immunohistochemistry (IHC). The effect of two commonly used dental resinous monomers on TEOE was evaluated for alterations in cell viability and barrier permeability. ALI/keratinocyte growth factor-supplemented (ALI-KGS) culture conditions led to the formation of an 8-20-layer thick, intercellularly-connected epithelial barrier. TEER values of ALI-KGS-developed TEOE decreased compared to all other tested conditions, and the established epithelium intensively expressed pCK. Exposure to dental monomers affected the integrity and architecture of TEOE, and induced cellular vacuolation, implicating hydropic degeneration. Despite structural modifications, the permeability of TEOE was not substantially affected after exposure to the monomers. In conclusion, the biological properties of the TEOE mimicking the physiological functional conditions and its value as biocompatibility assessment tool for dental materials were characterized.
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Affiliation(s)
- Foteini Machla
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Dentistry, Thessaloniki, Central Macedonia, Greece;
| | - Paraskevi Kyriaki Monou
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Pharmacy, Thessaloniki, Central Macedonia, Greece
- Center for Interdisciplinary Research and Innovation, Thessaloniki, Greece;
| | - Chrysanthi Bekiari
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Veterinary Medicine, Thessaloniki, Central Macedonia, Greece;
| | - Dimitrios Andreadis
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Dentistry, Thessaloniki, Central Macedonia, Greece;
| | - Evangelia Kofidou
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Veterinary Medicine, Thessaloniki, Central Macedonia, Greece;
| | - Emmanouel Panteris
- Aristotle University of Thessaloniki Faculty of Sciences, School of Biology, Thessaloniki, Central Macedonia, Greece;
| | - Orestis L Katsamenis
- University of Southampton Faculty of Engineering and Physical Sciences, Biomedical Imaging and X-ray Histology, Southampton, United Kingdom of Great Britain and Northern Ireland
- University of Southampton Institute for Life Sciences, Southampton, United Kingdom of Great Britain and Northern Ireland;
| | - Maria Kokoti
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Dentistry, Thessaloniki, Central Macedonia, Greece;
| | - Petros Koidis
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Dentistry, Thessaloniki, Central Macedonia, Greece;
| | - Imad About
- Aix-Marseille Université, Marseille, Provence-Alpes-Côte d'Azu, France;
| | - Dimitrios Fatouros
- Aristotle University of Thessaloniki Faculty of Health Sciences, School of Pharmacy, Thessaloniki, Central Macedonia, Greece
- Center for Interdisciplinary Research and Innovation, Thessaloniki, Greece;
| | - Athina Bakopoulou
- Aristotle University of Thessaloniki, School of Dentistry, University Campus, Thessaloniki, Greece, 54124;
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Gelin A, Masson-Meyers D, Amini F, Moharamzadeh K, Tayebi L. Collagen: The superior material for full-thickness oral mucosa tissue engineering. J Oral Biosci 2024; 66:511-518. [PMID: 38909983 DOI: 10.1016/j.job.2024.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 06/25/2024]
Abstract
BACKGROUND Tissue engineering has significantly progressed in developing full-thickness oral mucosa constructs designed to replicate the natural oral mucosa. These constructs serve as valuable in vitro models for biocompatibility testing and oral disease modeling and hold clinical potential for replacing damaged or lost oral soft tissue. However, one of the major challenges in tissue engineering of the oral mucosa is the identification of an appropriate scaffold with optimal porosity, interconnected porous networks, biodegradability, and biocompatibility. These characteristics facilitate cell migration, nutrient delivery, and vascularization. Various biomaterials have been investigated for constructing tissue-engineered oral mucosa models; collagen has demonstrated superior outcomes compared with other materials. HIGHLIGHT This review discusses the different types of tissue-engineered oral mucosa developed using various materials and includes articles published between January 2000 and December 2022 in PubMed and Google Scholar. The review focuses on the superiority of collagen-based scaffolds for tissue engineering of oral mucosa, explores in vitro applications, and discusses potential clinical applications. CONCLUSION Among the various scaffold materials used for engineering the connective tissue of the oral mucosa, collagen-based scaffolds possess excellent biological properties, offering high-quality oral mucosa constructs and high resemblance to the native human oral mucosa in terms of histology and expression of various differentiation markers.
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Affiliation(s)
- Alexandra Gelin
- Marquette University School of Dentistry, Milwaukee, WI, 53233, USA
| | | | - Fatemeh Amini
- School of Dentistry, Shahed University of Medical Sciences, Tehran, Iran
| | - Keyvan Moharamzadeh
- Hamdan Bin Mohammed College of Dental Medicine (HBMCDM), Mohammed Bin Rashid University of Medicine and Health Sciences (MBRU), Dubai, United Arab Emirates; School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
| | - Lobat Tayebi
- Marquette University School of Dentistry, Milwaukee, WI, 53233, USA.
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Rosa V, Silikas N, Yu B, Dubey N, Sriram G, Zinelis S, Lima AF, Bottino MC, Ferreira JN, Schmalz G, Watts DC. Guidance on the assessment of biocompatibility of biomaterials: Fundamentals and testing considerations. Dent Mater 2024:S0109-5641(24)00221-5. [PMID: 39129079 DOI: 10.1016/j.dental.2024.07.020] [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: 06/09/2024] [Revised: 07/22/2024] [Accepted: 07/24/2024] [Indexed: 08/13/2024]
Abstract
BACKGROUND Assessing the biocompatibility of materials is crucial for ensuring the safety and well-being of patients by preventing undesirable, toxic, immune, or allergic reactions, and ensuring that materials remain functional over time without triggering adverse reactions. To ensure a comprehensive assessment, planning tests that carefully consider the intended application and potential exposure scenarios for selecting relevant assays, cell types, and testing parameters is essential. Moreover, characterizing the composition and properties of biomaterials allows for a more accurate understanding of test outcomes and the identification of factors contributing to cytotoxicity. Precise reporting of methodology and results facilitates research reproducibility and understanding of the findings by the scientific community, regulatory agencies, healthcare providers, and the general public. AIMS This article aims to provide an overview of the key concepts associated with evaluating the biocompatibility of biomaterials while also offering practical guidance on cellular principles, testing methodologies, and biological assays that can support in the planning, execution, and reporting of biocompatibility testing.
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Affiliation(s)
- Vinicius Rosa
- Faculty of Dentistry, National University of Singapore, Singapore; ORCHIDS: Oral Care Health Innovations and Designs Singapore, National University of Singapore, Singapore.
| | - Nikolaos Silikas
- Dental Biomaterials, Dentistry, The University of Manchester, Manchester, United Kingdom.
| | - Baiqing Yu
- Faculty of Dentistry, National University of Singapore, Singapore.
| | - Nileshkumar Dubey
- ORCHIDS: Oral Care Health Innovations and Designs Singapore, National University of Singapore, Singapore; Division of Cariology and Operative Dentistry, Department of Comprehensive Dentistry, University of Maryland School of Dentistry, Baltimore, United States.
| | - Gopu Sriram
- Faculty of Dentistry, National University of Singapore, Singapore; ORCHIDS: Oral Care Health Innovations and Designs Singapore, National University of Singapore, Singapore.
| | - Spiros Zinelis
- School of Dentistry National and Kapodistrian University of Athens (NKUA), Greece.
| | - Adriano F Lima
- Dental Research Division, Paulista University, Sao Paulo, Brazil.
| | - Marco C Bottino
- School of Dentistry, University of Michigan, Ann Arbor, USA.
| | - Joao N Ferreira
- Center of Excellence for Innovation for Oral Health and Healthy Longevity, Faculty of Dentistry, Chulalongkorn University, Thailand.
| | - Gottfried Schmalz
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Regensburg, Germany; Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
| | - David C Watts
- School of Medical Sciences and Photon Science Institute, University of Manchester, United Kingdom.
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Muniraj G, Tan RHS, Dai Y, Wu R, Alberti M, Sriram G. Microphysiological Modeling of Gingival Tissues and Host-Material Interactions Using Gingiva-on-Chip. Adv Healthc Mater 2023; 12:e2301472. [PMID: 37758297 DOI: 10.1002/adhm.202301472] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 09/14/2023] [Indexed: 10/03/2023]
Abstract
Gingiva plays a crucial barrier role at the interface of teeth, tooth-supporting structures, microbiome, and external agents. To mimic this complex microenvironment, an in vitro microphysiological platform and biofabricated full-thickness gingival equivalents (gingiva-on-chip) within a vertically stacked microfluidic device is developed. This design allowed long-term and air-liquid interface culture, and host-material interactions under flow conditions. Compared to static cultures, dynamic cultures on-chip enabled the biofabrication of gingival equivalents with stable mucosal matrix, improved epithelial morphogenesis, and barrier features. Additionally, a diseased state with disrupted barrier function representative of gingival/oral mucosal ulcers is modeled. The apical flow feature is utilized to emulate the mechanical action of mouth rinse and integrate the assessment of host-material interactions and transmucosal permeation of oral-care formulations in both healthy and diseased states. Although the gingiva-on-chip cultures have thicker and more mature epithelium, the flow of oral-care formulations induced increased tissue disruption and cytotoxic features compared to static conditions. The realistic emulation of mouth rinsing action facilitated a more physiological assessment of mucosal irritation potential. Overall, this microphysiological system enables biofabrication of human gingiva equivalents in intact and ulcerated states, providing a miniaturized and integrated platform for downstream host-material and host-microbiome applications in gingival and oral mucosa research.
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Affiliation(s)
- Giridharan Muniraj
- Faculty of Dentistry, National University of Singapore, Singapore, 119085, Singapore
| | - Rachel Hui Shuen Tan
- Singapore Institute of Manufacturing Technology (SIMTech), Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
| | - Yichen Dai
- Faculty of Dentistry, National University of Singapore, Singapore, 119085, Singapore
| | - Ruige Wu
- Singapore Institute of Manufacturing Technology (SIMTech), Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
| | - Massimo Alberti
- Singapore Institute of Manufacturing Technology (SIMTech), Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
- REVIVO BioSystems Pte. Ltd., Singapore, 138623, Singapore
| | - Gopu Sriram
- Faculty of Dentistry, National University of Singapore, Singapore, 119085, Singapore
- ORCHIDS: Oral Care Health Innovations and Designs Singapore, National University of Singapore, Singapore, 119085, Singapore
- NUS Centre for Additive Manufacturing (AM.NUS), National University of Singapore, Singapore, 117602, Singapore
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Razali M, Chai WL, Omar RA, Ngeow WC. Contour Analysis of Three-Dimensional Peri-Implant Mucosal Model as an Endpoint Analysis of Photofunctionalization Effects on Implant Abutment Materials. MATERIALS (BASEL, SWITZERLAND) 2023; 16:5529. [PMID: 37629819 PMCID: PMC10456501 DOI: 10.3390/ma16165529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/01/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023]
Abstract
INTRODUCTION The objective of this study was to examine the effect of photofunctionalization on the soft-tissue contour formed at the interface of various abutment materials using end-point analyses obtained from the three-dimensional oral mucosal model (3D-OMMs). METHODS Commercially pure titanium (CPTi), alumina-toughened zirconia (ATZ), and yttria-stabilized zirconia (YSZ) made into discs shapes were classified into two groups: UV-treated (PTx) and non-treated (NTx). The materials in PTx groups were exposed to UV light for 12 min. Human gingival fibroblasts and TR146 epithelial cell lines co-cultured on the acellular dermal membrane were used to construct the 3D-OMM. After 4 days of culture, the discs were inserted into the holes prepared within the membrane of 3D-OMMs. The contour formed by the tissue was evaluated after 14 days of culture. RESULTS The UV treatment of abutment materials resulted in the formation of more non-pocket-tissue types among the PTx group (p = 0.002). Of all materials tested, soft tissue contour around YSZ showed higher scores for the non-pocket type in both non- and UV-treated groups. CONCLUSIONS The non-pocket type of tissue attachment was frequently found in all surfaces modified by photofunctionalization, particularly zirconia. The 3D-OMM can be used to evaluate the biological endpoints of implant surface modifications.
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Affiliation(s)
- Masfueh Razali
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia
| | - Wen Lin Chai
- Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia; (W.L.C.); (R.A.O.)
| | - Ros Anita Omar
- Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia; (W.L.C.); (R.A.O.)
| | - Wei Cheong Ngeow
- Department of Oral & Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia
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Effect of Three Chlorhexidine-Based Mouthwashes on Human Gingival Fibroblasts: An In Vitro Study. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12052417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mouthwashes containing chlorhexidine (CHX) are deemed to be associated with dose-dependent side effects, including burning sensation and taste alteration. To overcome these drawbacks, mouthwashes with CHX at lower concentrations with or without adjunctive agents are proposed. The aim of this in vitro study was to investigate the effects of three CHX-based mouthwashes on human gingival fibroblasts (HGFs). After 3 days of cell culture, groups were randomly treated for 30 s, 60 s or 120 s with (a) CHX 0.05% in combination with cetylpyridnium chloride (CPC) 0.05%; (b) CHX 0.1%; (c) CHX 0.2%; or (d) NaCl as control. Cell viability, cytotoxicity and apoptosis were evaluated at 2 h, 3 days and 6 days after the exposure to the different solutions. Similar cell viability values were found among the test groups at all time points. At day 0, higher cytotoxicity was measured in the group treated with CHX 0.02%, in particular after long application time (120 s), while no significant difference was found between CHX + CPC and the control group. All the investigated mouthwashes were well tolerated by HGF cells for the tested application times. The highest cytotoxic effect was observed for CHX 0.2%; therefore, clinicians should consider limiting its usage to carefully selected clinical situations.
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Real-Time Analysis of Antiproliferative Effects of Mouthwashes Containing Alcohol, Sodium Fluoride, Cetylpyridinium Chloride, and Chlorhexidine In Vitro. BIOMED RESEARCH INTERNATIONAL 2021; 2021:2610122. [PMID: 34676260 PMCID: PMC8526215 DOI: 10.1155/2021/2610122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 09/09/2021] [Accepted: 09/22/2021] [Indexed: 11/30/2022]
Abstract
Objectives In this study, the cytotoxic responses of six different over-the-counter mouthwashes on L929 cells were analyzed by two different techniques: the traditional colorimetric tetrazolium-based reduction assay (MTT) and the modern impedance-based real-time cell analysis (RTCA) system to investigate their biocompatibility in vitro. Thus, the investigation of the antiproliferative effects of the specified materials via different techniques is vital to reach this goal. Materials and Methods First, L929 mouse fibroblasts were exposed to the dilutions of mouthwashes for 2 minutes. After incubation, the tetrazolium reduction method was used to assess the metabolic viability of cells measured by colorimetric MTT assay and morphological inspection of cells was performed via phase-contrast microscopy. Furthermore, the effect of each mouthwash on the proliferation, morphology, and adhesion of L929 cells was monitored continuously by a noninvasive and label-free RTCA system for 140 h. Results Our data showed that all of the mouthwashes had varying cytotoxic effects on fibroblasts compared to the control group in MTT assay. In addition to that, RTCA technology has provided the growth kinetic profiles that can be used to analyze if the treatment is causing antimitotic or DNA-damaging effect on cells. Thus, analysis via this system can tell us the mechanism of toxicity behind the cell growth inhibition in vitro. Here, we found that only mouthwash 1 moderately maintained the viability of the L929 cells, yet displaying antimitotic effects and the other mouthwashes (mouthwash 2-mouthwash 6) showed toxicity via DNA-damaging effects. Conclusions Of the six types of mouthwash tested, the most biocompatible result was obtained from a mouthwash containing alcohol (i.e., mouthwash 1). On the other hand, sodium fluoride- (NaF-) and cetylpyridinium chloride- (CPC-) containing mouthwash (i.e., mouthwash 2) showed the most cytotoxic effect.
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Nishiyama K, Akagi T, Iwai S, Akashi M. Construction of Vascularized Oral Mucosa Equivalents Using a Layer-by-Layer Cell Coating Technology. Tissue Eng Part C Methods 2020; 25:262-275. [PMID: 30838934 DOI: 10.1089/ten.tec.2018.0337] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
There have been many advances in tissue engineering with respect to in vitro and in vivo models of oral mucosa equivalents (OMEs). To apply in vitro reconstructed oral mucosa models to regenerative medicine and alternatives to animal testing, it is necessary to develop the technology of reconstructing different types of oral tissues, such as control of epithelial differentiation and introduction of appendages. We previously reported that functional three-dimensional (3D) tissue models could be quickly constructed by using a layer-by-layer (LbL) cell coating technique that assembles extracellular matrix (ECM) nanofilms to a cell surface. In this study, 3D human OMEs composed of lamina-propria, keratinized or non-keratinized epithelium, and blood capillaries were constructed by using the LbL cell coating technology. Human oral mucosal fibroblasts (HOMFs) were coated with ECM nanofilms and accumulated for the construction of oral mucosal lamina-propria. To construct OMEs with keratinized or non-keratinized epithelium, human oral keratinocytes isolated from gingiva (human oral gingival keratinocytes: HOGKs) or human oral keratinocytes isolated from oral mucosa (human oral mucosal keratinocytes: HOMKs) were used in this study. We further studied the construction of epithelialized OMEs with density- and size-controlled blood capillary networks by using human umbilical vein endothelial cells (HUVECs). It was revealed that these constructions had barrier functions in accordance with their histological characterization. The OMEs with keratinization (K-OMEs) showed higher transepithelial electrical resistance (TEER) values compared with OMEs with non-keratinization (N-OMEs). The constructed epithelialized OMEs with blood capillaries are useful for in vitro/ex vivo research models and regenerative medicine as in oral tissue regeneration. The results suggest that OMEs with oral tissue appendages are more promising alternatives to animal testing and can be applied to the design of in vitro oral models that mimic human tissue organs.
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Affiliation(s)
- Kyoko Nishiyama
- 1 Department of Oral and Maxillofacial Surgery II, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Takami Akagi
- 2 Building Block Science Joint Research Chair, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Soichi Iwai
- 1 Department of Oral and Maxillofacial Surgery II, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Mitsuru Akashi
- 2 Building Block Science Joint Research Chair, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
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Barker E, AlQobaly L, Shaikh Z, Franklin K, Moharamzadeh K. Implant Soft-Tissue Attachment Using 3D Oral Mucosal Models-A Pilot Study. Dent J (Basel) 2020; 8:E72. [PMID: 32645887 PMCID: PMC7558259 DOI: 10.3390/dj8030072] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/23/2020] [Accepted: 07/03/2020] [Indexed: 01/25/2023] Open
Abstract
PURPOSE The aim of this study was to investigate soft-tissue attachment to different metal, ceramic, and polymer implant surfaces using an inflamed, three-dimensional (3D), tissue-engineered, human oral mucosal model, as well as multiple-endpoint qualitative and quantitative biological approaches. METHODS Normal human oral fibroblasts, OKF6/TERT-2 keratinocytes and THP-1 monocytes were cultured, and full-thickness, 3D oral mucosal models were engineered inside tissue culture inserts. Sand-blasted and acid-etched (SLA) and machined (M) titanium-zirconium alloy (TiZr; commercially known as Roxolid; Institut Straumann AG, Switzerland), ceramic (ZrO2), and polyether ether ketone (PEEK) rods (Ø 4 mm × 8 mm) were inserted into the center of tissue-engineered oral mucosa following a Ø 4mm punch biopsy. Inflammation was simulated with addition of the lipopolysaccharide (LPS) of Escherichia coli (E. coli) and tumor necrosis factor (TNF)-alpha to the culture medium. Implant soft-tissue attachment was assessed using histology, an implant pull-test with PrestoBlue assay, and scanning electron microscopy (SEM). RESULTS Inflamed, full-thickness, 3D human oral mucosal models with inserted implants were successfully engineered and histologically characterized. The implant pull-test with PrestoBlue assay showed higher viability of the tissue that remained attached to the TiZr-SLA surface compared to the other test groups. This difference was statistically significant (p < 0.05). SEM analysis showed evidence of epithelial cell attachment on different implant surfaces. CONCLUSIONS The inflamed, 3D, oral mucosal model has the potential to be used as a suitable in vitro test system for visualization and quantification of implant soft-tissue attachment. The results of our study indicate greater soft tissue attachment to TiZr-SLA compared to TiZr-M, ceramic, and PEEK surfaces.
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Affiliation(s)
| | | | | | | | - Keyvan Moharamzadeh
- School of Clinical Dentistry, University of Sheffield, Western Bank, Sheffield S10 2TN, UK; (E.B.); (L.A.); (Z.S.); (K.F.)
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Alizadehgharib S, Östberg AK, Dahlstrand Rudin A, Dahlgren U, Christenson K. The effects of the dental methacrylates TEGDMA, Bis-GMA, and UDMA on neutrophils in vitro. Clin Exp Dent Res 2020; 6:439-447. [PMID: 32543782 PMCID: PMC7453771 DOI: 10.1002/cre2.296] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 03/25/2020] [Accepted: 03/28/2020] [Indexed: 12/30/2022] Open
Abstract
Objectives The prevalent usage of methacrylates in modern dentistry demands good knowledge of their biological impacts. While there have been several studies demonstrating the effects of different methacrylic monomers on mononuclear white blood cells, very little is known about the effects caused by these monomers on neutrophilic granulocytes. The objective of this study was to add novel knowledge about how neutrophils are affected by exposure to triethylene glycol dimethacrylate (TEGDMA), urethane dimethacrylate (UDMA), and bisphenol A glycol dimethacrylate (Bis‐GMA) alone or in combinations. Materials and Methods Isolated neutrophils were cultured in the presence or absence of methacrylates. The IL‐8 release was measured using a DuoSet ELISA development kit. Apoptosis and necrosis were analyzed using flow cytometry. The formation of neutrophil extracellular traps (NETs) was investigated using Sytox green DNA staining combined with microscopically examination of released DNA and myeloperoxidase (MPO). Results The release of IL‐8 was significantly increased after exposure to TEGDMA, Bis‐GMA, UDMA, or TEGDMA in combination with Bis‐GMA or UDMA compared to the unstimulated controls. Exposure to TEGDMA, UDMA, and Bis‐GMA for 24 hr separately or in combination did not affect apoptosis or necrosis of the exposed neutrophils. NET structures were formed by neutrophils after exposure to the different combinations of the methacrylates. Conclusion The combination of TEGDMA and Bis‐GMA had a synergistic proinflammatory effect on neutrophils by increasing the release of IL‐8 and the formation of NET structures. The changes in the normal functions of neutrophils caused by methacrylate exposure may lead to altered inflammatory response and relate to previously reported adverse immune reactions caused by these substances.
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Affiliation(s)
- Sara Alizadehgharib
- Department of Oral Microbiology and Immunology, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ann-Karin Östberg
- Department of Oral Microbiology and Immunology, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Agnes Dahlstrand Rudin
- Department of Oral Microbiology and Immunology, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ulf Dahlgren
- Department of Oral Microbiology and Immunology, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Karin Christenson
- Department of Oral Microbiology and Immunology, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Assessment of a 72-hour repeated exposure to Swedish snus extract and total particulate matter from 3R4F cigarette smoke on gingival organotypic cultures. Food Chem Toxicol 2019; 125:252-270. [DOI: 10.1016/j.fct.2018.12.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 12/11/2018] [Accepted: 12/30/2018] [Indexed: 12/14/2022]
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12
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Juráňová J. Illuminating the cellular and molecular mechanism of the potential toxicity of methacrylate monomers used in biomaterials. Drug Chem Toxicol 2019; 43:266-278. [DOI: 10.1080/01480545.2018.1488860] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Jana Juráňová
- Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacky University, Hněvotínská 3, Olomouc, Czech Republic
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacky University, Hněvotínská 5, Olomouc, Czech Republic
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Rahimi C, Rahimi B, Padova D, Rooholghodos SA, Bienek DR, Luo X, Kaufman G, Raub CB. Oral mucosa-on-a-chip to assess layer-specific responses to bacteria and dental materials. BIOMICROFLUIDICS 2018; 12:054106. [PMID: 30310527 PMCID: PMC6158033 DOI: 10.1063/1.5048938] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 09/06/2018] [Indexed: 05/24/2023]
Abstract
The human oral mucosa hosts a diverse microbiome and is exposed to potentially toxic biomaterials from dental restoratives. Mucosal health is partly determined by cell and tissue responses to challenges such as dental materials and pathogenic bacteria. An in vitro model to rapidly determine potential layer-specific responses would lead to a better understanding of mucosal homeostasis and pathology. Therefore, this study aimed to develop a co-cultured microfluidic mucosal model on-a-chip to rapidly assess mucosal remodeling and the responses of epithelial and subepithelial layers to challenges typically found in the oral environment. A gingival fibroblast-laden collagen hydrogel was assembled in the central channel of a three-channel microfluidic chamber with interconnecting pores, followed by a keratinocyte layer attached to the collagen exposed in the pores. This configuration produced apical and subepithelial side channels capable of sustaining flow. Keratinocyte, fibroblast, and collagen densities were optimized to create a co-culture tissue-like construct stable over one week. Cells were stained and imaged with epifluorescence microscopy to confirm layer characteristics. As proof-of-concept, the mucosal construct was exposed separately to a dental monomer, 2-hydroxylethyl methacrylate (HEMA), and the oral bacteria Streptococcus mutans. Exposure to HEMA lowered mucosal cell viability, while exposure to the bacteria lowered trans-epithelial electrical resistance. These findings suggest that the oral mucosa-on-a-chip is useful for studying oral mucosal interactions with bacteria and biomaterials with a histology-like view of the tissue layers.
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Affiliation(s)
- Christopher Rahimi
- Department of Biomedical Engineering, The Catholic University of America, 620 Michigan Avenue NE, Washington, District of Columbia 20064, USA
| | - Benjamin Rahimi
- Department of Biomedical Engineering, The Catholic University of America, 620 Michigan Avenue NE, Washington, District of Columbia 20064, USA
| | - Dominic Padova
- Department of Biomedical Engineering, The Catholic University of America, 620 Michigan Avenue NE, Washington, District of Columbia 20064, USA
| | - Seyed A. Rooholghodos
- Department of Mechanical Engineering, The Catholic University of America, 620 Michigan Avenue NE, Washington, District of Columbia 20064, USA
| | - Diane R. Bienek
- ADA Foundation, Volpe Research Center, 100 Bureau Drive, Stop #8546, Gaithersburg, Maryland 20899, USA
| | - Xiaolong Luo
- Department of Mechanical Engineering, The Catholic University of America, 620 Michigan Avenue NE, Washington, District of Columbia 20064, USA
| | - Gili Kaufman
- ADA Foundation, Volpe Research Center, 100 Bureau Drive, Stop #8546, Gaithersburg, Maryland 20899, USA
| | - Christopher B. Raub
- Department of Biomedical Engineering, The Catholic University of America, 620 Michigan Avenue NE, Washington, District of Columbia 20064, USA
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14
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Zanetti F, Sewer A, Scotti E, Titz B, Schlage WK, Leroy P, Kondylis A, Vuillaume G, Iskandar AR, Guedj E, Trivedi K, Schneider T, Elamin A, Martin F, Frentzel S, Ivanov NV, Peitsch MC, Hoeng J. Assessment of the impact of aerosol from a potential modified risk tobacco product compared with cigarette smoke on human organotypic oral epithelial cultures under different exposure regimens. Food Chem Toxicol 2018; 115:148-169. [PMID: 29505817 DOI: 10.1016/j.fct.2018.02.062] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 02/20/2018] [Accepted: 02/27/2018] [Indexed: 12/19/2022]
Abstract
Cigarette smoke (CS) is affecting considerably the oral mucosa. Heating, instead of burning, tobacco reduces consistently the amount of toxic compounds and may exert a lower impact on oral health than combusted cigarettes. The carbon-heated tobacco product 1.2 (CHTP1.2) is a potential modified risk tobacco product (MRTP) based on heat-not-burn technology. Using a systems toxicology assessment framework, we compared the effects of exposure to CHTP1.2 aerosol with those of CS from a reference cigarette (3R4F). Human organotypic cultures derived from buccal and gingival epithelia were exposed acutely (28-min) or repeatedly (28 min/day for 3 days), respectively, to two matching concentrations of CHTP1.2 aerosol or 3R4F CS, and a non-diluted (100%) CHTP1.2 aerosol. The results showed an absence of cytotoxicity, reduction in pathophysiological alterations, toxicological marker proteins, and inflammatory mediators following exposure to CHTP1.2 aerosol compared with 3R4F CS. Changes in mRNA and miRNA expression were linked by an integrative analysis approach, suggesting a regulatory role of miRNAs in several smoke/disease-relevant biological processes induced by 3R4F CS. The identification of mechanisms by which potential MRTPs can reduce the impact of tobacco use on biological systems is of great importance in understanding the molecular basis of the smoking harm reduction paradigm.
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Affiliation(s)
- Filippo Zanetti
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland.
| | - Alain Sewer
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Elena Scotti
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Bjoern Titz
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Walter K Schlage
- Biology Consultant, Max-Baermann-Str. 21, 51429 Bergisch Gladbach, Germany
| | - Patrice Leroy
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Athanasios Kondylis
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Gregory Vuillaume
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Anita R Iskandar
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Emmanuel Guedj
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Keyur Trivedi
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Thomas Schneider
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Ashraf Elamin
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Florian Martin
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Stefan Frentzel
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Nikolai V Ivanov
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Manuel C Peitsch
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Julia Hoeng
- PMI R&D, Philip Morris Products S.A., Part of Philip Morris International Group of Companies, Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
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15
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Alizadehgharib S, Östberg AK, Dahlgren U. Triethylene glycol dimethacrylate: adjuvant properties and effect on cytokine production. ACTA BIOMATERIALIA ODONTOLOGICA SCANDINAVICA 2017; 4:1-9. [PMID: 29230430 PMCID: PMC5717717 DOI: 10.1080/23337931.2017.1409075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/20/2017] [Indexed: 11/16/2022]
Abstract
Objective: Leakage of monomers from dental fillings due to incomplete curing is very common. The objective of the present study was to examine the cytokine profile in cells exposed to triethyleneglycol dimethacrylate (TEGDMA) and the adjuvant properties of TEGDMA. Materials and methods: Human peripheral blood mononuclear cells were exposed to TEGDMA (500 and 1000 μM) for 24 h in vitro. Bio-Plex Pro™ assays were used for analysis and detection of cytokines. In vivo, BALB/c mice were immunized subcutaneously in the base of the tail with TEGDMA in combination with ovalbumin (OVA). Results: The cytokine levels of IL-8, IL-18, GRO-α and MCP-1 were significantly increased for both concentrations. IL-1β, IL-6 and TNF-α was only significantly increased in cultures exposed to 500 μM TEGDMA. The concentration of TNF-α was significantly decreased in cultures exposed to 1000 μM TEGDMA. Animals immunized with OVA co-administrated with TEGDMA had a significantly higher IgE and IgG anti-OVA antibody levels in blood than animals immunized with OVA only. Conclusions: TEGDMA affects production of proinflammatory cytokines IL-1β, IL-6, IL-8, IL-18 and TNF-α. This inflammatogenic capacity renders TEGDMAs adjuvant properties, which may interfere with the homeostasis between the immune system and the indigenous microflora in the oral cavity.
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Affiliation(s)
- Sara Alizadehgharib
- Department of Oral Microbiology and Immunology, University of Gothenburg, The Sahlgrenska Academy, Institute of OdontologyGothenburgSweden
| | - Anna-Karin Östberg
- Department of Oral Microbiology and Immunology, University of Gothenburg, The Sahlgrenska Academy, Institute of OdontologyGothenburgSweden
| | - Ulf Dahlgren
- Department of Oral Microbiology and Immunology, University of Gothenburg, The Sahlgrenska Academy, Institute of OdontologyGothenburgSweden
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16
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Alizadehgharib S, Östberg A, Dahlgren U. Effects of the methacrylate/acrylate monomers HEMA, TEGDMA, DEGDA, and EMA on the immune system. Clin Exp Dent Res 2017; 3:227-234. [PMID: 29744206 PMCID: PMC5839251 DOI: 10.1002/cre2.93] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 09/14/2017] [Accepted: 10/13/2017] [Indexed: 11/13/2022] Open
Abstract
Incomplete curing of dental fillings may lead to leakage of methacrylate/acrylate monomers, which may come in contact with different cells of the immune system in oral tissues. Very little is known about the different immunologic effects caused by these methacrylates/acrylates. The objective of the present study was to study if and how the methacrylate/acrylate monomers ethyl methacrylate (EMA) and diethylene glycol diacrylate (DEGDA) affect the immune system in vivo and in vitro in comparison to 2-hydroxyethyl methacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA). Human peripheral blood mononuclear cells were exposed to the different monomers (500 and 1000 μM) for 24 hr in vitro. BioPlex Pro™ assays were used for cytokine analysis. In vivo, BALB/c mice were immunized subcutaneously at the base of the tail with HEMA, TEGDMA, EMA, or DEGDA in combination with ovalbumin (OVA) in order to study adjuvant properties of the 4 monomers. Peripheral blood mononuclear cells exposed to DEGDA had viability less than 50% of the cells. A pattern was observed where the levels of most cytokines were elevated after exposure to HEMA or TEGDMA. Since that, many cells died after DEGDA-exposure, the only observed cytokine secretion was a significantly increased production of interleukin-18. In the in vivo experiments, all mice immunized with DEGDA died after the booster injection. Mice receiving OVA in combination with HEMA, TEGDMA, or EMA developed a higher immunoglobulin G anti-OVA antibody levels compared to the group immunized with OVA alone. We could not demonstrate any significant difference in antibody levels among the mice receiving the various methacrylate/acrylate monomers. The different monomers affected the production, increase and decrease, of different cytokines in vitro but resulted also in vivo in increased antibody production and T-cell activity.
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Affiliation(s)
- Sara Alizadehgharib
- Department of Oral Microbiology and ImmunologyUniversity of Gothenburg, The Sahlgrenska Academy, Institute of OdontologyPO Box 450, SE‐405 30GothenburgSweden
| | - Anna‐Karin Östberg
- Department of Oral Microbiology and ImmunologyUniversity of Gothenburg, The Sahlgrenska Academy, Institute of OdontologyPO Box 450, SE‐405 30GothenburgSweden
| | - Ulf Dahlgren
- Department of Oral Microbiology and ImmunologyUniversity of Gothenburg, The Sahlgrenska Academy, Institute of OdontologyPO Box 450, SE‐405 30GothenburgSweden
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17
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Song G, Banov D, Bassani AS, Valdez BC. Evaluation of the Safety, Cell Migration, and Mucoadhesive Properties of a Mucoadhesive Polymer Blend in Human Oral Mucosa. AAPS PharmSciTech 2017; 18:1617-1623. [PMID: 27645471 DOI: 10.1208/s12249-016-0630-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 09/06/2016] [Indexed: 11/30/2022] Open
Abstract
The efficacy of active pharmaceutical ingredients (API) in compounded medications for oral mucosa greatly depends on the composition of the base. Here, we assessed the safety, facilitation of cell migration, and mucoadhesive properties of a newly developed mucoadhesive polymer blend (MPB) which contains pullulan, tamarindus indica polysaccharide, and sodium hyaluronate. No cell death was observed when human oral keratinocyte (HOK) and fibroblast (HOrF) cells were exposed to 1% MPB for 24 h. Epithelial cells in a 3D buccal tissue model (EpiOral) were unaffected when exposed to 50% MPB for 20 h whereas 1% Triton X-100 killed 93% cells after 4.5 h. The expressions of cytokines IL1α and IL1β and cell proliferation markers PCNA, CYCLIN A, and CYCLIN D1 in EpiOral tissue did not increase suggesting that MPB is neither an irritant nor a mitogen. Markers of apoptosis such as cleavage of CASPASES 8/9, upregulation of pro-apoptosis NOXA protein, and downregulation of anti-apoptosis XIAP protein were observed in Triton X-100-treated cells but not in cells exposed to MPB. The migration of HOK and HOrF cells was stimulated by MPB, and the expression of E-CADHERIN in the EpiOral tissues was unaffected. Moreover, MPB showed stronger mucoadhesion on the human EpiOral tissue model compared with a reference product. We conclude that MPB can safely deliver API within the oral mucosa, facilitate cell migration, and may increase drug efficacy through its strong mucoadhesive property.
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18
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Zanetti F, Titz B, Sewer A, Lo Sasso G, Scotti E, Schlage WK, Mathis C, Leroy P, Majeed S, Torres LO, Keppler BR, Elamin A, Trivedi K, Guedj E, Martin F, Frentzel S, Ivanov NV, Peitsch MC, Hoeng J. Comparative systems toxicology analysis of cigarette smoke and aerosol from a candidate modified risk tobacco product in organotypic human gingival epithelial cultures: A 3-day repeated exposure study. Food Chem Toxicol 2017; 101:15-35. [PMID: 28025120 DOI: 10.1016/j.fct.2016.12.027] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/01/2016] [Accepted: 12/20/2016] [Indexed: 12/17/2022]
Abstract
Smoking is one of the major lifestyle-related risk factors for periodontal diseases. Modified risk tobacco products (MRTP) offer a promising alternative in the harm reduction strategy for adult smokers unable to quit. Using a systems toxicology approach, we investigated and compared the exposure effects of a reference cigarette (3R4F) and a heat-not-burn technology-based candidate MRTP, the Tobacco Heating System (THS) 2.2. Human gingival epithelial organotypic cultures were repeatedly exposed (3 days) for 28 min at two matching concentrations of cigarette smoke (CS) or THS2.2 aerosol. Results showed only minor histopathological alterations and minimal cytotoxicity upon THS2.2 aerosol exposure compared to CS (1% for THS2.2 aerosol vs. 30% for CS, at the high concentration). Among the 14 proinflammatory mediators analyzed, only 5 exhibited significant alterations with THS2.2 exposure compared with 11 upon CS exposure. Transcriptomic and metabolomic analysis indicated a general reduction of the impact in THS2.2 aerosol-exposed samples with respect to CS (∼79% lower biological impact for the high THS2.2 aerosol concentration compared to CS, and 13 metabolites significantly perturbed for THS2.2 vs. 181 for CS). This study indicates that exposure to THS2.2 aerosol had a lower impact on the pathophysiology of human gingival organotypic cultures than CS.
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Affiliation(s)
- Filippo Zanetti
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland.
| | - Bjoern Titz
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Alain Sewer
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Giuseppe Lo Sasso
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Elena Scotti
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Walter K Schlage
- Biology Consultant, Max-Baermann-Str. 21, 51429 Bergisch Gladbach, Germany
| | - Carole Mathis
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Patrice Leroy
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Shoaib Majeed
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Laura Ortega Torres
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | | | - Ashraf Elamin
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Keyur Trivedi
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Emmanuel Guedj
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Florian Martin
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Stefan Frentzel
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Nikolai V Ivanov
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Manuel C Peitsch
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
| | - Julia Hoeng
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
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19
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Yoshikawa K, Sekino J, Imamura K, Ota K, Kita D, Saito A. In vitro Effect of Mouthrinse Containing Essential Oils on Proliferation and Migration of Gingival Epithelial Cells. Phytother Res 2016; 30:1113-8. [PMID: 27059802 DOI: 10.1002/ptr.5613] [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: 12/12/2015] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 11/07/2022]
Abstract
We aimed to investigate in vitro the effects of mouthrinses containing essential oils (EOs) on proliferation and migration of gingival epithelial cells. Human gingival epithelial cells were treated with predetermined dilutions of commercially available EO mouthrinses with or without ethanol and a mouthrinse containing cetyl pyridinium chloride (CPC) for 60 s. Cell proliferation was evaluated using WST-1 assay. Cell migration was assessed using a wound closure model. Within 10 s of exposure to EO mouthrinse without ethanol, the epithelial cells became aberrant and shrank. No statistically significant difference in cell migration or proliferation was observed among cells pretreated by the EO mouthrinse with ethanol, CPC mouthrinse and control (phosphate buffered saline). In contrast, the EO mouthrinse without ethanol significantly reduced cell proliferation (p < 0.001) to approximately 20% relative to control. As for the EO mouthrinse without ethanol, it was not possible to assess its effect on cell migration using this model, because treated cells could be easily detached from the culture plate upon scratch, possibly because of the surfactant ingredient in the formulation. Within the limitations of the study, the EO mouthrinse with ethanol exerted no inhibitory effect on proliferation and migration of the gingival epithelial cells. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Kouki Yoshikawa
- Department of Periodontology, Tokyo Dental College, Tokyo, Japan
| | - Jin Sekino
- Department of Periodontology, Tokyo Dental College, Tokyo, Japan
| | - Kentaro Imamura
- Department of Periodontology, Tokyo Dental College, Tokyo, Japan
| | - Koki Ota
- Department of Periodontology, Tokyo Dental College, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Japan
| | - Daichi Kita
- Department of Periodontology, Tokyo Dental College, Tokyo, Japan
| | - Atsushi Saito
- Department of Periodontology, Tokyo Dental College, Tokyo, Japan.,Oral Health Science Center, Tokyo Dental College, Japan
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20
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Kinikoglu B, Damour O, Hasirci V. Tissue engineering of oral mucosa: a shared concept with skin. J Artif Organs 2014; 18:8-19. [PMID: 25326194 DOI: 10.1007/s10047-014-0798-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 10/07/2014] [Indexed: 12/17/2022]
Abstract
Tissue-engineered oral mucosa, in the form of epithelial cell sheets or full-thickness oral mucosa equivalents, is a potential solution for many patients with congenital defects or with tissue loss due to diseases or tumor excision following a craniofacial cancer diagnosis. In the laboratory, it further serves as an in vitro model, alternative to in vivo testing of oral care products, and provides insight into the behavior of the oral mucosal cells in healthy and pathological tissues. This review covers the old and new generation scaffold types and materials used in oral mucosa engineering; discusses similarities and differences between oral mucosa and skin, the methods developed to reconstruct oral mucosal defects; and ends with future perspectives on oral mucosa engineering.
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Affiliation(s)
- Beste Kinikoglu
- Department of Medical Biology, School of Medicine, Acibadem University, 34742, Istanbul, Turkey,
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21
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Hayakumo S, Arakawa S, Takahashi M, Kondo K, Mano Y, Izumi Y. Effects of ozone nano-bubble water on periodontopathic bacteria and oral cells - in vitro studies. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2014; 15:055003. [PMID: 27877715 PMCID: PMC5099676 DOI: 10.1088/1468-6996/15/5/055003] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 08/13/2014] [Indexed: 06/06/2023]
Abstract
The aims of the present study were to evaluate the bactericidal activity of a new antiseptic agent, ozone nano-bubble water (NBW3), against periodontopathogenic bacteria and to assess the cytotoxicity of NBW3 against human oral cells. The bactericidal activities of NBW3 against representative periodontopathogenic bacteria, Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) were evaluated using in vitro time-kill assays. The cytotoxicity of NBW3 was evaluated using three-dimensional human buccal and gingival tissue models. The numbers of colony forming units (CFUs)/mL of P. gingivalis and A. actinomycetemcomitans exposed to NBW3 dropped to below the lower limit of detection (<10 CFUs mL-1) after only 0.5 min of exposure. There were only minor decreases in the viability of oral tissue cells after 24 h of exposure to NBW3. These results suggest that NBW3 possesses potent bactericidal activity against representative periodontopathogenic bacteria and is not cytotoxic to cells of human oral tissues. The use of NBW3 as an adjunct to periodontal therapy would be promising.
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Affiliation(s)
- Sae Hayakumo
- Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Shinichi Arakawa
- Department of Lifetime Oral Health Care Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Masayoshi Takahashi
- National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569, Japan
| | - Keiko Kondo
- Department of Lifetime Oral Health Care Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Yoshihiro Mano
- Hyperbaric Medical Center, Hospital of Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Yuichi Izumi
- Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
- Global Center of Excellence (GCOE) Program, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
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22
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Chai WL, Moharamzadeh K, van Noort R, Emanuelsson L, Palmquist A, Brook IM. Contour analysis of an implant--soft tissue interface. J Periodontal Res 2013; 48:663-70. [PMID: 23442017 DOI: 10.1111/jre.12062] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVE Studies of peri-implant soft tissue on in vivo models are commonly based on histological sections prepared using undecalcified or 'fracture' techniques. These techniques require the cutting or removal of implant during the specimen preparation process. The aim of this study is to explore a new impression technique that does not require any cutting or removal of implant for contour analysis of soft tissue around four types of titanium (Ti) surface roughness using an in vitro three-dimensional oral mucosal model (3D OMM). METHODS The 3D OMM was constructed by co-culturing a keratinocyte cell line TR146 and human oral fibroblasts on to an acellular dermis scaffold. On the fourth day, a Ti disk was placed into the model. Four types of Ti surface topographies, i.e. polished, machined, sandblasted and anodized were tested. After 10 d of culture, the specimens were processed based on undecalcified (ground sectioning), electropolishing and impression techniques for contour analysis of the implant-soft tissue interface. RESULTS Under light microscopic examination of the ground and electropolishing sections, it was found that the cell line-based oral mucosa formed a peri-implant-like epithelium attachment on to all four types of Ti surfaces. In contour analysis, the most common contour observed between the cell line-based oral mucosa and Ti surface was at an angle ranging between 45° and 90°. CONCLUSION The in vitro cell line-based 3D OMM formed a peri-implant-like epithelium at the implant-soft tissue interface. The contour of the implant-soft tissue interface for the four types of Ti surface was not significantly different.
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Affiliation(s)
- W L Chai
- Department of General Dental Practice and Oral & Maxillofacial Imaging, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
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23
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Chai WL, Brook IM, Palmquist A, van Noort R, Moharamzadeh K. The biological seal of the implant-soft tissue interface evaluated in a tissue-engineered oral mucosal model. J R Soc Interface 2012; 9:3528-38. [PMID: 22915635 DOI: 10.1098/rsif.2012.0507] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
For dental implants, it is vital that an initial soft tissue seal is achieved as this helps to stabilize and preserve the peri-implant tissues during the restorative stages following placement. The study of the implant-soft tissue interface is usually undertaken in animal models. We have developed an in vitro three-dimensional tissue-engineered oral mucosal model (3D OMM), which lends itself to the study of the implant-soft tissue interface as it has been shown that cells from the three-dimensional OMM attach onto titanium (Ti) surfaces forming a biological seal (BS). This study compares the quality of the BS achieved using the three-dimensional OMM for four types of Ti surfaces: polished, machined, sandblasted and anodized (TiUnite). The BS was evaluated quantitatively by permeability and cell attachment tests. Tritiated water (HTO) was used as the tracing agent for the permeability test. At the end of the permeability test, the Ti discs were removed from the three-dimensional OMM and an Alamar Blue assay was used for the measurement of residual cells attached to the Ti discs. The penetration of the HTO through the BS for the four types of Ti surfaces was not significantly different, and there was no significant difference in the viability of residual cells that attached to the Ti surfaces. The BS of the tissue-engineered oral mucosa around the four types of Ti surface topographies was not significantly different.
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Affiliation(s)
- Wen L Chai
- Department of General Dental Practice and Oral and Maxillofacial Imaging, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia.
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Vlachojannis C, Winsauer H, Chrubasik S. Effectiveness and safety of a mouthwash containing essential oil ingredients. Phytother Res 2012; 27:685-91. [PMID: 22761009 DOI: 10.1002/ptr.4762] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 05/21/2012] [Accepted: 05/23/2012] [Indexed: 01/14/2023]
Abstract
The mouthwash, Listerine®, was compounded in 1879 from four essential oils. Later, the oils were replaced by one ingredient per oil with approximately 25% ethanol as a vehicle to keep them in solution. From then on, Listerine® was no longer a medicinal plant product. In 2003, a review by the FDA Subcommittee on Oral Health Care Drug Products for Over-the-Counter Human Use concluded that the product is effective and safe, and a review of studies published in the meantime showed that Listerine® fulfils the consensus criteria for an effective antigingivitis/antiplaque product. However, concerns have been raised about the long-term safety of some of the ingredients, particularly the ethanol content, and in the light of these concerns, the evidence has been re-examined for both the efficacy and safety of Listerine®. In summary, the studies support the claim that Listerine® shows benefit for oral health, but the concerns over its safety remain to be clarified. Until these have been addressed, high risk populations (children, alcohol addicts, patients with genetic deficiencies in ethanol metabolism) should use alcohol-free mouthwashes for the maintenance of oral health.
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Moharamzadeh K, Colley H, Murdoch C, Hearnden V, Chai WL, Brook IM, Thornhill MH, Macneil S. Tissue-engineered oral mucosa. J Dent Res 2012; 91:642-50. [PMID: 22266525 DOI: 10.1177/0022034511435702] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Advances in tissue engineering have permitted the three-dimensional (3D) reconstruction of human oral mucosa for various in vivo and in vitro applications. Tissue-engineered oral mucosa have been further optimized in recent years for clinical applications as a suitable graft material for intra-oral and extra-oral repair and treatment of soft-tissue defects. Novel 3D in vitro models of oral diseases such as cancer, Candida, and bacterial invasion have been developed as alternatives to animal models for investigation of disease phenomena, their progression, and treatment, including evaluation of drug delivery systems. The introduction of 3D oral mucosal reconstructs has had a significant impact on the approaches to biocompatibility evaluation of dental materials and oral healthcare products as well as the study of implant-soft tissue interfaces. This review article discusses the recent advances in tissue engineering and applications of tissue-engineered human oral mucosa.
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Affiliation(s)
- K Moharamzadeh
- School of Clinical Dentistry, University of Sheffield, Claremont Crescent, Sheffield, S10 2TA, UK.
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McGinley E, Moran G, Fleming G. Base-metal dental casting alloy biocompatibility assessment using a human-derived three-dimensional oral mucosal model. Acta Biomater 2012; 8:432-8. [PMID: 21889621 DOI: 10.1016/j.actbio.2011.08.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 08/15/2011] [Accepted: 08/17/2011] [Indexed: 02/02/2023]
Abstract
Nickel-chromium (Ni-Cr) alloys used in fixed prosthodontics have been associated with type IV Ni-induced hypersensitivity. We hypothesised that the full-thickness human-derived oral mucosa model employed for biocompatibility testing of base-metal dental alloys would provide insights into the mechanisms of Ni-induced toxicity. Primary oral keratinocytes and gingival fibroblasts were seeded onto Alloderm™ and maintained until full thickness was achieved prior to Ni-Cr and cobalt-chromium (Co-Cr) alloy disc exposure (2-72 h). Biocompatibility assessment involved histological analyses with cell viability measurements, oxidative stress responses, inflammatory cytokine expression and cellular toxicity analyses. Inductively coupled plasma mass spectrometry analysis determined elemental ion release levels. We detected adverse morphology with significant reductions in cell viability, significant increases in oxidative stress, inflammatory cytokine expression and cellular toxicity for the Ni-Cr alloy-treated oral mucosal models compared with untreated oral mucosal models, and adverse effects were increased for the Ni-Cr alloy that leached the most Ni. Co-Cr demonstrated significantly enhanced biocompatibility compared with Ni-Cr alloy-treated oral mucosal models. The human-derived full-thickness oral mucosal model discriminated between dental alloys and provided insights into the mechanisms of Ni-induced toxicity, highlighting potential clinical relevance.
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Chai WL, Brook IM, Emanuelsson L, Palmquist A, van Noort R, Moharamzadeh K. Ultrastructural analysis of implant-soft tissue interface on a three dimensional tissue-engineered oral mucosal model. J Biomed Mater Res A 2011; 100:269-77. [DOI: 10.1002/jbm.a.33245] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 08/18/2011] [Accepted: 08/19/2011] [Indexed: 11/06/2022]
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Türkez H, Togar B, Arabaci T. Evaluation of genotoxicity after application of Listerine(R) on human lymphocytes by micronucleus and single cell gel electrophoresis assays. Toxicol Ind Health 2011; 28:271-5. [PMID: 22033428 DOI: 10.1177/0748233711410918] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Listerine (LN) is one of the most commonly used mouth rinses worldwide although very limited information is available concerning its genotoxicity. In another view, the biological safety profile of oral care products is frequently assumed on the basis of simplistic test models. Therefore, the present study was undertaken to investigate the in vitro genotoxic potential of LN using micronucleus and single cell gel electrophoresis tests as genetic endpoints. Different concentrations of LN (0-100% of ml/culture, v/v) were applied to whole human blood cultures (n = 5). The result of the present study showed that there were no statistically significant differences (p > 0.05) between the control group and the groups treated with LN alone in both analysed endpoints. In conclusion, our result first demonstrated the absence of genotoxicity of LN on human lymphocytes.
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Affiliation(s)
- Hasan Türkez
- Faculty of Science, Department of Biology, Atatürk University, Erzurum, Turkey
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Koschier F, Kostrubsky V, Toole C, Gallo MA. In vitro effects of ethanol and mouthrinse on permeability in an oral buccal mucosal tissue construct. Food Chem Toxicol 2011; 49:2524-9. [DOI: 10.1016/j.fct.2011.06.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 06/01/2011] [Accepted: 06/07/2011] [Indexed: 10/18/2022]
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Yang J, Deol G, Myangar N. Retention of o-cymen-5-ol and zinc on reconstructed human gingival tissue from a toothpaste formulation. Int Dent J 2011; 61 Suppl 3:41-5. [DOI: 10.1111/j.1875-595x.2011.00048.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Fröhlich E, Meindl C, Roblegg E, Griesbacher A, Pieber TR. Cytotoxity of nanoparticles is influenced by size, proliferation and embryonic origin of the cells used for testing. Nanotoxicology 2011; 6:424-39. [DOI: 10.3109/17435390.2011.586478] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Chai WL, Moharamzadeh K, Brook IM, Emanuelsson L, Palmquist A, van Noort R. Development of a novel model for the investigation of implant-soft tissue interface. J Periodontol 2010; 81:1187-95. [PMID: 20450401 DOI: 10.1902/jop.2010.090648] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND In dental implant treatment, the long-term prognosis is dependent on the biologic seal formed by the soft tissue around the implant. The in vitro investigation of the implant-soft tissue interface is usually carried out using a monolayer cell-culture model that lacks a polarized-cell phenotype. This study developed a tissue-engineered three-dimensional oral mucosal model (3D OMM) to investigate the implant-soft tissue interface. METHODS A 3D OMM was constructed using primary human oral keratinocytes and fibroblasts cultured on a skin-derived scaffold at an air-liquid interface. A titanium implant was inserted into the engineered oral mucosa and further cultured to establish epithelial attachment. The 3D OMM was characterized using basic histology and immunostaining for cytokeratin (CK) 10 and CK13. Histomorphometric analyses of the implant-soft tissue interface were carried out using a light-microscopy (LM) examination of ground sections and semi-thin sections as well as scanning electron microscopy (SEM). RESULTS Immunohistochemistry analyses suggests that the engineered oral mucosa closely resembles the normal oral mucosa. The LM and SEM examinations reveal that the 3D OMM forms an epithelial attachment on the titanium surface. CONCLUSION The 3D OMM provided mimicking peri-implant features as seen in an in vivo model and has the potential to be used as a relevant alternative model to assess implant-soft tissue interactions.
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Affiliation(s)
- Wen Lin Chai
- Department of General Dental Practice and Oral and Maxillofacial Imaging, University of Malaya, Malaya, Malaysia.
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