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Hassibi H, Farsinejad A, Dabiri S, Voosough D, Mortezaeizadeh A, Kheirandish R, Azari O. Allogenic Bone Graft Enriched by Periosteal Stem Cell and Growth Factors for Osteogenesis in Critical Size Bone Defect in Rabbit Model: Histopathological and Radiological Evaluation. IRANIAN JOURNAL OF PATHOLOGY 2020; 15:205-216. [PMID: 32754216 PMCID: PMC7354065 DOI: 10.30699/ijp.2020.101715.2013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Accepted: 04/09/2020] [Indexed: 01/05/2023]
Abstract
Background & Objective: This study aimed to investigate the effect of decellularized allogeneic bone graft enriched by periosteal stem cells (PSCs) and growth factors on the bone repair process in a rabbit model, which could be used in many orthopedic procedures. Methods: In this experimental study, a critical size defect (CSD) (10 mm) was created in the radial diaphysis of 40 rabbits. In group A, the defect was left intact with no medical intervention. In group B, the defect was filled by a decellularized bone graft. In group C, the defect was implanted by a decellularized bone graft enriched with platelet growth factors. In group D, the defect was treated by a decellularized bone graft seeded by periosteal mesenchymal stem cells (MSCs). Also, in group E, the defect was filled by a decellularized bone graft enriched with platelet growth factors and periosteal MSCs. Radiological evaluation was done on the first day and then in the second, fourth, and eighth weeks after the operation. The specimens were harvested on the 28th and 56th postoperative days and evaluated for histopathological criteria. Results: The radiologic and microscopic analysis of the healing process in bone defects of the treated groups (C, D, and E) revealed more advanced repair criteria than those of groups A and B significantly (P<0.05). Conclusion: Based on this study, it appears that implantation of concentrated PSCs in combination with growth factors and allogeneic cortical bone graft is an effective therapy for the repair of large bone defects.
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Affiliation(s)
- Hadi Hassibi
- Department of Veterinary Surgery, Shahid Bahonar University of Kerman, Kerman, Iran
| | - Alireza Farsinejad
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medicine, Kerman University of Medical Science, Kerman, Iran
| | - Shahriar Dabiri
- Pathology and stem cell Research Center, Department of Pathology, Kerman University of Medical Sciences, Kerman, Iran
| | - Darioush Voosough
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran
| | - Abbas Mortezaeizadeh
- Pathology and stem cell Research Center, Department of Pathology, Kerman University of Medical Sciences, Kerman, Iran
| | - Reza Kheirandish
- Department of Pathobiology, Faculty of Veterinary Medicine, Shahid Bahnoar University of Kerman, Kerman, Iran
| | - Omid Azari
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran
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Chawla S, Sharma A, Bandyopadhyay A, Ghosh S. Developmental Biology-Inspired Strategies To Engineer 3D Bioprinted Bone Construct. ACS Biomater Sci Eng 2018; 4:3545-3560. [DOI: 10.1021/acsbiomaterials.8b00757] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Shikha Chawla
- Regenerative Engineering Laboratory, Department of Textile Technology, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Aarushi Sharma
- Regenerative Engineering Laboratory, Department of Textile Technology, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Amitabha Bandyopadhyay
- Department of Biological Sciences & Bioengineering (BSBE), Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sourabh Ghosh
- Regenerative Engineering Laboratory, Department of Textile Technology, Indian Institute of Technology Delhi, New Delhi 110016, India
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Intrinsic Osteoinductivity of Porous Titanium Scaffold for Bone Tissue Engineering. Int J Biomater 2017; 2017:5093063. [PMID: 28814954 PMCID: PMC5549492 DOI: 10.1155/2017/5093063] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 06/07/2017] [Indexed: 01/08/2023] Open
Abstract
Large bone defects and nonunions are serious complications that are caused by extensive trauma or tumour. As traditional therapies fail to repair these critical-sized defects, tissue engineering scaffolds can be used to regenerate the damaged tissue. Highly porous titanium scaffolds, produced by selective laser sintering with mechanical properties in range of trabecular bone (compressive strength 35 MPa and modulus 73 MPa), can be used in these orthopaedic applications, if a stable mechanical fixation is provided. Hydroxyapatite coatings are generally considered essential and/or beneficial for bone formation; however, debonding of the coatings is one of the main concerns. We hypothesised that the titanium scaffolds have an intrinsic potential to induce bone formation without the need for a hydroxyapatite coating. In this paper, titanium scaffolds coated with hydroxyapatite using electrochemical method were fabricated and osteoinductivity of coated and noncoated scaffolds was compared in vitro. Alizarin Red quantification confirmed osteogenesis independent of coating. Bone formation and ingrowth into the titanium scaffolds were evaluated in sheep stifle joints. The examinations after 3 months revealed 70% bone ingrowth into the scaffold confirming its osteoinductive capacity. It is shown that the developed titanium scaffold has an intrinsic capacity for bone formation and is a suitable scaffold for bone tissue engineering.
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Application of Additive Manufacturing in Oral and Maxillofacial Surgery. J Oral Maxillofac Surg 2015; 73:2408-18. [DOI: 10.1016/j.joms.2015.04.019] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 04/13/2015] [Accepted: 04/14/2015] [Indexed: 01/07/2023]
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Emara KM, Diab RA, Emara AK. Recent biological trends in management of fracture non-union. World J Orthop 2015; 6:623-628. [PMID: 26396938 PMCID: PMC4573506 DOI: 10.5312/wjo.v6.i8.623] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 05/31/2015] [Accepted: 07/17/2015] [Indexed: 02/06/2023] Open
Abstract
Bone regeneration is a complex, well-orchestrated physiological process of bone formation, which can be seen during normal fracture healing, and is involved in continuous remodelling throughout adult life. Currently, there is a plethora of different strategies to augment the impaired or “insufficient” bone-regeneration process, including the “gold standard” autologous bone graft, free fibula vascularised graft, allograft implantation, and use of growth factors, osteoconductive scaffolds, osteoprogenitor cells and distraction osteogenesis. Improved “local” strategies in terms of tissue engineering and gene therapy, or even “systemic” enhancement of bone repair, are under intense investigation, in an effort to overcome the limitations of the current methods, to produce bone-graft substitutes with biomechanical properties that are as identical to normal bone as possible, to accelerate the overall regeneration process, or even to address systemic conditions, such as skeletal disorders and osteoporosis. An improved understanding of the molecular and cellular events that occur during bone repair and remodeling has led to the development of biologic agents that can augment the biological microenvironment and enhance bone repair. Orthobiologics, including stem cells, osteoinductive growth factors, osteoconductive matrices, and anabolic agents, are available clinically for accelerating fracture repair and treatment of compromised bone repair situations like delayed unions and nonunions. A lack of standardized outcome measures for comparison of biologic agents in clinical fracture repair trials, frequent off-label use, and a limited understanding of the biological activity of these agents at the bone repair site have limited their efficacy in clinical applications.
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Papadimitropoulos A, Scotti C, Bourgine P, Scherberich A, Martin I. Engineered decellularized matrices to instruct bone regeneration processes. Bone 2015; 70:66-72. [PMID: 25260931 DOI: 10.1016/j.bone.2014.09.007] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 08/25/2014] [Accepted: 09/06/2014] [Indexed: 12/20/2022]
Abstract
Despite the significant progress in the field of bone tissue engineering, cell-based products have not yet reached the stage of clinical adoption. This is due to the uncertain advantages from the standard-of-care, combined with challenging cost-and regulatory-related issues. Novel therapeutic approaches could be based on exploitation of the intrinsic regenerative capacity of bone tissue, provided the development of a deeper understanding of its healing mechanisms. While it is well-established that endogenous progenitors can be activated toward bone formation by overdoses of single morphogens, the challenge to stimulate the healing processes by coordinated and controlled stimulation of specific cell populations remains open. Here, we review the recent approaches to generate osteoinductive materials based on the use of decellularized extracellular matrices (ECM) as reservoirs of multiple factors presented at physiological doses and through the appropriate ligands. We then propose the generation of customized engineered and decellularized ECM (i) as a tool to better understand the processes of bone regeneration and (ii) as safe and effective "off-the-shelf" bone grafts for clinical use. This article is part of a Special Issue entitled Stem Cells and Bone.
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Affiliation(s)
- Adam Papadimitropoulos
- Department of Surgery, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland; Department of Biomedicine, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland; Cellec Biotek AG, Vogesenstrasse 135, 4056 Basel, Switzerland
| | - Celeste Scotti
- IRCCS Istituto Ortopedico Galeazzi, Via R. Galeazzi, 20161 Milan, Italy
| | - Paul Bourgine
- Department of Surgery, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland; Department of Biomedicine, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland
| | - Arnaud Scherberich
- Department of Surgery, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland; Department of Biomedicine, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland
| | - Ivan Martin
- Department of Surgery, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland; Department of Biomedicine, University Hospital Basel, University of Basel, Hebelstrasse 20, 4031 Basel, Switzerland.
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Gómez-Barrena E, Rosset P, Lozano D, Stanovici J, Ermthaller C, Gerbhard F. Bone fracture healing: cell therapy in delayed unions and nonunions. Bone 2015; 70:93-101. [PMID: 25093266 DOI: 10.1016/j.bone.2014.07.033] [Citation(s) in RCA: 273] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 07/26/2014] [Accepted: 07/28/2014] [Indexed: 12/14/2022]
Abstract
Bone fracture healing impairment related to mechanical problems has been largely corrected by advances in fracture management. Better protocols, more strict controls of time and function, and hardware and surgical technique evolution have contributed to better prognosis, even in complex fractures. However, atrophic nonunion persists in clinical cases where, for different reasons, the osteogenic capability is impaired. When this is the case, a better understanding of the basic mechanisms under bone repair and augmentation techniques may put in perspective the current possibilities and future opportunities. Among those, cell therapy particularly aims to correct this insufficient osteogenesis. However, the launching of safe and efficacious cell therapies still requires substantial amount of research, especially clinical trials. This review will envisage the current clinical trials on bone healing augmentation based on cell therapy, with the experience provided by the REBORNE Project, and the insight from investigator-driven clinical trials on advanced therapies towards the future. This article is part of a Special Issue entitled Stem Cells and Bone.
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Affiliation(s)
- Enrique Gómez-Barrena
- Dept. of Orthopaedic Surgery and Traumatology, Hospital La Paz-IdiPAZ, Universidad Autónoma de Madrid, Madrid, Spain.
| | - Philippe Rosset
- Service of Orthopaedic Surgery and Traumatology, CHU Tours, Université François-Rabelais de Tours, PRES Centre-Val de Loire Université, Tours, France; Inserm U957, Laboratoire de Physiopathologie de la Résorption Osseuse et Thérapie des Tumeurs Osseuses Primitives (LPRO), Faculté de Médecine, Université de Nantes, France
| | - Daniel Lozano
- Metabolic Bone Research Unit, Instituto de Investigación Sanitaria FJD, Madrid, Spain
| | - Julien Stanovici
- Service of Orthopaedic Surgery and Traumatology, CHU Tours, Université François-Rabelais de Tours, PRES Centre-Val de Loire Université, Tours, France; Inserm U957, Laboratoire de Physiopathologie de la Résorption Osseuse et Thérapie des Tumeurs Osseuses Primitives (LPRO), Faculté de Médecine, Université de Nantes, France
| | - Christian Ermthaller
- Klinik für Unfallchirurgie-, Hand-, Plastische und Wiederherstellungschirurgie Zentrum für Chirurgie Universitätsklinikum Ulm, Ulm, Germany
| | - Florian Gerbhard
- Klinik für Unfallchirurgie-, Hand-, Plastische und Wiederherstellungschirurgie Zentrum für Chirurgie Universitätsklinikum Ulm, Ulm, Germany
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Vandrovcova M, Douglas TEL, Heinemann S, Scharnweber D, Dubruel P, Bacakova L. Collagen-lactoferrin fibrillar coatings enhance osteoblast proliferation and differentiation. J Biomed Mater Res A 2014; 103:525-33. [DOI: 10.1002/jbm.a.35199] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 03/31/2014] [Accepted: 04/04/2014] [Indexed: 01/29/2023]
Affiliation(s)
- Marta Vandrovcova
- Department of Biomaterials and Tissue Engineering; Institute of Physiology, Academy of Sciences of the Czech Republic; Videnska 1083, 14220 Prague 4 Czech Republic
| | - Timothy E. L. Douglas
- Polymer Chemistry and Biomaterials (PBM) Group, Department of Organic Chemistry; Ghent University; Krijgslaan 281 S4 9000 Ghent Belgium
| | - Sascha Heinemann
- Biomimetic Materials and Biomaterial Analytics Group, Institute of Material Science, Max Bergmann Center of Biomaterials; Technische Universität Dresden; Budapester Strasse 27 01069 Dresden Germany
| | - Dieter Scharnweber
- Biomaterial Development Group, Institute of Material Science, Max Bergmann Center of Biomaterials; Technische Universität Dresden; Budapester Strasse 27 01069 Dresden Germany
| | - Peter Dubruel
- Polymer Chemistry and Biomaterials (PBM) Group, Department of Organic Chemistry; Ghent University; Krijgslaan 281 S4 9000 Ghent Belgium
| | - Lucie Bacakova
- Department of Biomaterials and Tissue Engineering; Institute of Physiology, Academy of Sciences of the Czech Republic; Videnska 1083, 14220 Prague 4 Czech Republic
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Rosset P, Deschaseaux F, Layrolle P. Cell therapy for bone repair. Orthop Traumatol Surg Res 2014; 100:S107-12. [PMID: 24411717 DOI: 10.1016/j.otsr.2013.11.010] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 11/08/2013] [Accepted: 11/15/2013] [Indexed: 02/07/2023]
Abstract
When natural bone repair mechanisms fail, autologous bone grafting is the current standard of care. The osteogenic cells and bone matrix in the graft provide the osteo-inductive and osteo-conductive properties required for successful bone repair. Bone marrow (BM) mesenchymal stem cells (MSCs) can differentiate into osteogenic cells. MSC-based cell therapy holds promise for promoting bone repair. The amount of MSCs available from iliac-crest aspirates is too small to be clinically useful, and either concentration or culture must therefore be used to expand the MSC population. MSCs can be administered alone via percutaneous injection or implanted during open surgery with a biomaterial, usually biphasic hydroxyapatite/β-calcium-triphosphate granules. Encouraging preliminary results have been obtained in patients with delayed healing of long bone fractures or avascular necrosis of the femoral head. Bone tissue engineering involves in vitro MSC culturing on biomaterials to obtain colonisation of the biomaterial and differentiation of the cells. The biomaterial-cell construct is then implanted into the zone to be treated. Few published data are available on bone tissue engineering. Much work remains to be done before determining whether this method is suitable for the routine filling of bone tissue defects. Increasing cell survival and promoting implant vascularisation are major challenges. Improved expertise with culturing techniques, together with the incorporation of regulatory requirements, will open the way to high-quality clinical trials investigating the usefulness of cell therapy as a method for achieving bone repair. Cell therapy avoids the drawbacks of autologous bone grafting, preserving the bone stock and diminishing treatment invasiveness.
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Affiliation(s)
- P Rosset
- Service de chirurgie orthopédique 2, hôpital Trousseau, Université François-Rabelais de Tours, CHU de Tours, 37044 Tours cedex 09, France; Inserm U957, Laboratoire de physiopathologie de la résorption osseuse et thérapie des tumeurs osseuses primitives (LPRO), Faculté de Médecine, Université de Nantes, Nantes, France.
| | - F Deschaseaux
- StromaLab, UMR CNRS 5273, U1031 Inserm, Établissement Français du Sang Pyrénées-Méditerranée, Université P.-Sabatier, Toulouse, France
| | - P Layrolle
- Inserm U957, Laboratoire de physiopathologie de la résorption osseuse et thérapie des tumeurs osseuses primitives (LPRO), Faculté de Médecine, Université de Nantes, Nantes, France
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West NX, Lussi A, Seong J, Hellwig E. Scaffold-free microtissues: differences from monolayer cultures and their potential in bone tissue engineering. Clin Oral Investig 2013; 17:9-17. [PMID: 22695872 PMCID: PMC3585766 DOI: 10.1007/s00784-012-0763-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Accepted: 05/23/2012] [Indexed: 12/16/2022]
Abstract
OBJECTIVES Cell-based therapies for bone augmentation after tooth loss and for the treatment of periodontal defects improve healing defects. Usually, osteogenic cells or stem cells are cultivated in 2D primary cultures, before they are combined with scaffold materials, even though this means a loss of the endogenous 3D microenvironment for the cells. Moreover, the use of single-cell suspensions for the inoculation of scaffolds or for the direct application into an area of interest has the disadvantages of low initial cell numbers and susceptibility to unwanted cellular distribution, respectively. MATERIALS AND METHODS We addressed the question whether an alternative to monolayer cultures, namely 3D microtissues, has the potential to improve osteogenic tissue engineering and its clinical outcome. RESULTS By contrast, to monolayer cultures, osteogenic differentiation of 3D microtissues is enhanced by mimicking in vivo conditions. It seems that the osteogenic differentiation in microtissues is enhanced by strong integrin-extracellular matrix interaction and by stronger autocrine BMP2 signaling. Moreover, microtissues are less prone to wash out by body fluids and allow the precise administration of large cell numbers. CONCLUSION Microtissue cultures have closer characteristics with cells in vivo and their enhanced osteogenic differentiation makes scaffold-free microtissues a promising concept in osteogenic tissue engineering. CLINICAL RELEVANCE Microtissues are particularly suitable for tissue engineering because they improve seeding efficiency of biomaterials by increasing the cell load of a scaffold. This results in accelerated osteogenic tissue formation and could contribute to earlier implant stability in mandibular bone augmentation.
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Affiliation(s)
- N. X. West
- />Clinical Trials Unit, Department of Oral and Dental Sciences, Bristol Dental Hospital, Lower Maudlin Street, Bristol, BS1 2LY UK
| | - A. Lussi
- />Department of Operative Dentistry, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - J. Seong
- />Clinical Trials Unit, Department of Oral and Dental Sciences, Bristol Dental Hospital, Lower Maudlin Street, Bristol, BS1 2LY UK
| | - E. Hellwig
- />Department of Operative Dentistry and Periodontology, Dental School and Hospital Dentistry, University Medical Center Freiburg, Freiburg im Breisgau, Germany
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Osteodifferentiation of human preadipocytes induced by strontium released from hydrogels. Int J Biomater 2012; 2012:865291. [PMID: 22927856 PMCID: PMC3423935 DOI: 10.1155/2012/865291] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Accepted: 06/21/2012] [Indexed: 02/07/2023] Open
Abstract
In recent years, there has been an increasing interest in interactive application principles of biology and engineering for the development of valid biological systems for tissue regeneration, such as for the treatment of bone fractures or skeletal defects. The application of stem cells together with biomaterials releasing bioactive factors promotes the formation of bone tissue by inducing proliferation and/or cell differentiation. In this study, we used a clonal cell line from human adipose tissue-derived mesenchymal stem cells (hADSCs or preadipocytes), named PA2-E12, to evaluate the effects of strontium (Sr2+) released in the culture medium from an amidated carboxymethylcellulose (CMCA) hydrogel enriched with different Sr2+ concentrations on osteodifferentiation. The osteoinductive effect was evaluated through both the expression of alkaline phophatase (ALP) activity and the hydroxyapatite (HA) production during 42 days of induction. Present data have shown that Sr2+ released from CMCA promotes the osteodifferentiation induced by an osteogenic medium as shown by the increase of ALP activity at 7 and 14 days and of HA production at 14 days. In conclusion, the use of biomaterials able to release in situ osteoinductive agents, like Sr2+, could represent a new strategy for future applications in bone tissue engineering.
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West NX, Lussi A, Seong J, Hellwig E. Scaffold-free microtissues: differences from monolayer cultures and their potential in bone tissue engineering. Clin Oral Investig 2012; 17 Suppl 1:S9-19. [PMID: 22695872 PMCID: PMC3585766 DOI: 10.1007/s00784-012-0887-x] [Citation(s) in RCA: 133] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Accepted: 11/21/2012] [Indexed: 12/13/2022]
Abstract
Objectives The paper’s aim is to review dentin hypersensitivity (DHS), discussing pain mechanisms and aetiology. Materials and methods Literature was reviewed using search engines with MESH terms, DH pain mechanisms and aetiology (including abrasion, erosion and periodontal disease). Results The many hypotheses proposed for DHS attest to our lack of knowledge in understanding neurophysiologic mechanisms, the most widely accepted being the hydrodynamic theory. Dentin tubules must be patent from the oral environment to the pulp. Dentin exposure, usually at the cervical margin, is due to a variety of processes involving gingival recession or loss of enamel, predisposing factors being periodontal disease and treatment, limited alveolar bone, thin biotype, erosion and abrasion. Conclusions The current pain mechanism of DHS is thought to be the hydrodynamic theory. The initiation and progression of DHS are influenced by characteristics of the teeth and periodontium as well as the oral environment and external influences. Risk factors are numerous often acting synergistically and always influenced by individual susceptibility. Clinical relevance Whilst the pain mechanism of DHS is not well understood, clinicians need to be mindful of the aetiology and risk factors in order to manage patients’ pain and expectations and prevent further dentin exposure with subsequent sensitivity.
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Affiliation(s)
- N. X. West
- />Clinical Trials Unit, Department of Oral and Dental Sciences, Bristol Dental Hospital, Lower Maudlin Street, Bristol, BS1 2LY UK
| | - A. Lussi
- />Department of Operative Dentistry, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - J. Seong
- />Clinical Trials Unit, Department of Oral and Dental Sciences, Bristol Dental Hospital, Lower Maudlin Street, Bristol, BS1 2LY UK
| | - E. Hellwig
- />Department of Operative Dentistry and Periodontology, Dental School and Hospital Dentistry, University Medical Center Freiburg, Freiburg im Breisgau, Germany
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Colnot C. Cell sources for bone tissue engineering: insights from basic science. TISSUE ENGINEERING PART B-REVIEWS 2011; 17:449-57. [PMID: 21902612 DOI: 10.1089/ten.teb.2011.0243] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
One of the goals of bone tissue engineering is to design delivery methods for skeletal stem/progenitor cells to repair or replace bone. Although the materials used to retain cells play a central role in the quality of the constructs, the source of cells is key for bone regeneration. Bone marrow is the most common cell source, but other tissues are now being explored, such as the periosteum, fat, muscle, cord blood, and embryonic or induced pluripotent stem cells. The therapeutic effect of exogenous stem/progenitor cells is accepted, yet their contribution to bone repair is not well defined. The in vitro osteo- and/or chondrogenic potential of these skeletal progenitors do not necessarily predict their differentiation potential in vivo and their function may be affected by their ability to home correctly to bone. This review provides an overview of animal models used to test the efficacy of cell-based approaches. We examine the mechanisms of endogenous cell recruitment during bone repair and compare the role of local versus systemic cell recruitment. We discuss how the normal repair process can help define efficacious cell sources for bone tissue engineering and improve their methods of delivery.
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Affiliation(s)
- Céline Colnot
- INSERM U781, Tour Lavoisier 2ème étage, Hôpital Necker-Enfants Malades, Paris, France.
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