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Nesic D, Schaefer BM, Sun Y, Saulacic N, Sailer I. 3D Printing Approach in Dentistry: The Future for Personalized Oral Soft Tissue Regeneration. J Clin Med 2020; 9:E2238. [PMID: 32679657 PMCID: PMC7408636 DOI: 10.3390/jcm9072238] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 12/21/2022] Open
Abstract
Three-dimensional (3D) printing technology allows the production of an individualized 3D object based on a material of choice, a specific computer-aided design and precise manufacturing. Developments in digital technology, smart biomaterials and advanced cell culturing, combined with 3D printing, provide promising grounds for patient-tailored treatments. In dentistry, the "digital workflow" comprising intraoral scanning for data acquisition, object design and 3D printing, is already in use for manufacturing of surgical guides, dental models and reconstructions. 3D printing, however, remains un-investigated for oral mucosa/gingiva. This scoping literature review provides an overview of the 3D printing technology and its applications in regenerative medicine to then describe 3D printing in dentistry for the production of surgical guides, educational models and the biological reconstructions of periodontal tissues from laboratory to a clinical case. The biomaterials suitable for oral soft tissues printing are outlined. The current treatments and their limitations for oral soft tissue regeneration are presented, including "off the shelf" products and the blood concentrate (PRF). Finally, tissue engineered gingival equivalents are described as the basis for future 3D-printed oral soft tissue constructs. The existing knowledge exploring different approaches could be applied to produce patient-tailored 3D-printed oral soft tissue graft with an appropriate inner architecture and outer shape, leading to a functional as well as aesthetically satisfying outcome.
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Affiliation(s)
- Dobrila Nesic
- Division of Fixed Prosthodontics and Biomaterials, University Clinic of Dental Medicine, University of Geneva, Rue Michel-Servet 1, CH-1211 Geneva 4, Switzerland; (Y.S.); (I.S.)
| | | | - Yue Sun
- Division of Fixed Prosthodontics and Biomaterials, University Clinic of Dental Medicine, University of Geneva, Rue Michel-Servet 1, CH-1211 Geneva 4, Switzerland; (Y.S.); (I.S.)
| | - Nikola Saulacic
- Department of Cranio-Maxillofacial Surgery, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 10, CH-3010 Bern, Switzerland;
| | - Irena Sailer
- Division of Fixed Prosthodontics and Biomaterials, University Clinic of Dental Medicine, University of Geneva, Rue Michel-Servet 1, CH-1211 Geneva 4, Switzerland; (Y.S.); (I.S.)
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Abstract
Currently, the gold standard for reconstruction after rhinectomy or severe trauma to the nose, includes transposition of autologous mucosal flaps plus autologous cartilage grating and coverage using a skin flap. Difficulties with this approach arise where; cartilage and mucosa harvested from autologous donor sites is insufficient to achieve a passable aesthetic and functional reconstruction. Skin flaps are often bulky, poor color matches with hair follicles that reduce the aesthetic quality of the reconstruction. We suggest that tissue engineering could be a source of functional replacement tissues for nasal reconstructive surgery. However, the advancement of such an approach is dependent on the dissemination of scientific information into the clinical community, regarding the engineering of tissues such as mucosa, skin, and cartilage. This paper therefore reviews how the tissue engineering strategies available for producing clinically viable tissues could help resolve issues around reconstructing the human nose.
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Kretlow JD, Shi M, Young S, Spicer PP, Demian N, Jansen JA, Wong ME, Kasper FK, Mikos AG. Evaluation of soft tissue coverage over porous polymethylmethacrylate space maintainers within nonhealing alveolar bone defects. Tissue Eng Part C Methods 2010; 16:1427-38. [PMID: 20524844 PMCID: PMC3003916 DOI: 10.1089/ten.tec.2010.0046] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 04/09/2010] [Indexed: 12/27/2022] Open
Abstract
Current treatment of traumatic craniofacial injuries often involves early free tissue transfer, even if the recipient site is contaminated or lacks soft tissue coverage. There are no current tissue engineering strategies to definitively regenerate tissues in such an environment at an early time point. For a tissue engineering approach to be employed in the treatment of such injuries, a two-stage approach could potentially be used. The present study describes methods for fabrication, characterization, and processing of porous polymethylmethacrylate (PMMA) space maintainers for temporary retention of space in bony craniofacial defects. Carboxymethylcellulose hydrogels were used as a porogen. Implants with controlled porosity and pore interconnectivity were fabricated by varying the ratio of hydrogel:polymer and the amount of carboxymethylcellulose within the hydrogel. The in vivo tissue response to the implants was observed by implanting solid, low-porosity, and high-porosity implants (n = 6) within a nonhealing rabbit mandibular defect that included an oral mucosal defect to allow open communication between the oral cavity and the mandibular defect. Oral mucosal wound healing was observed after 12 weeks and was complete in 3/6 defects filled with solid PMMA implants and 5/6 defects filled with either a low- or high-porosity PMMA implant. The tissue response around and within the pores of the two formulations of porous implants tested in vivo was characterized, with the low-porosity implants surrounded by a minimal but well-formed fibrous capsule in contrast to the high-porosity implants, which were surrounded and invaded by almost exclusively inflammatory tissue. On the basis of these results, PMMA implants with limited porosity hold promise for temporary implantation and space maintenance within clean/contaminated bone defects.
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Affiliation(s)
| | - Meng Shi
- Department of Bioengineering, Rice University, Houston, Texas
| | - Simon Young
- Department of Bioengineering, Rice University, Houston, Texas
- Department of Oral and Maxillofacial Surgery, The University of Texas Health Science Center at Houston, Houston, Texas
| | | | - Nagi Demian
- Department of Oral and Maxillofacial Surgery, The University of Texas Health Science Center at Houston, Houston, Texas
| | - John A. Jansen
- Department of Periodontology and Biomaterials, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Mark E. Wong
- Department of Oral and Maxillofacial Surgery, The University of Texas Health Science Center at Houston, Houston, Texas
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Vinzenz K, Holle J, Würinger E. Reconstruction of the maxilla with prefabricated scapular flaps in noma patients. Plast Reconstr Surg 2008; 121:1964-1973. [PMID: 18520882 DOI: 10.1097/prs.0b013e3181706dd6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Noma (cancrum oris) is a devastating gangrenous disease that leads to severe tissue destruction in the face and is associated with a high rate of mortality. When untreated, it results in disfiguring midface defects and severe scarring. Ideal reconstruction of complex maxillofacial defects requires the restitution of bone, dental implants, soft tissue, and the thin and durable lining of the oral and paranasal cavities. Prefabricated composite grafts from the scapula are used to restore the maxilla in patients with this disease. METHODS A new concept of osteosynthesis involving titanium plates connected to dental implants, achieving greater mechanical stability of the reconstructed bony framework, is described. Nine complex midface defects were reconstructed with dermis-prelaminated scapular flaps. A bone flap from the lateral margin of the scapula was taken and osseointegrated implants were inserted. The bone flap was then prelaminated with dermis and covered with a Gore-Tex sheath to prevent adhesion. Two to 3 months later, the composite flap was transferred to the midface. RESULTS Restoration of a maxilla with pneumatized paranasal cavities and a keratinized attached epithelium covering the alveolus and hard palate was successfully performed in all noma patients. The reconstructed "masticatory gingiva" and osseointegrated dental implants enabled patients to exercise oral functions shortly after surgery. CONCLUSION Long-term observation of selected noma patients showed restoration of oral function and stability of the maxilla after several years.
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Affiliation(s)
- Kurt Vinzenz
- Vienna, Austria From the Department of Plastic and Reconstructive Surgery, Wilhelminenspital Vienna, and the Department of Oral and Maxillofacial Surgery, Evangelisches Krankenhaus Vienna
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Moharamzadeh K, Brook IM, Van Noort R, Scutt AM, Thornhill MH. Tissue-engineered oral mucosa: a review of the scientific literature. J Dent Res 2007; 86:115-24. [PMID: 17251509 DOI: 10.1177/154405910708600203] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Tissue-engineered oral mucosal equivalents have been developed for clinical applications and also for in vitro studies of biocompatibility, mucosal irritation, disease, and other basic oral biology phenomena. This paper reviews different tissue-engineering strategies used for the production of human oral mucosal equivalents, their relative advantages and drawbacks, and their applications. Techniques used for skin tissue engineering that may possibly be used for in vitro reconstruction of human oral mucosa are also discussed.
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Affiliation(s)
- K Moharamzadeh
- School of Clinical Dentistry, University of Sheffield, Claremont Crescent, Sheffield, S10 2TA, United Kingdom.
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de Diego Rodríguez E, Roca Edreira A, Villanueva Peña A, Meana Infiesta A, Gómez Llames S, Martín García B, Gómez Ortega JM. [In vitro three-dimensional reconstruction of human bladder mucosa]. Actas Urol Esp 2006; 30:195-205. [PMID: 16700211 DOI: 10.1016/s0210-4806(06)73423-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The purpose of this study is to apply the in vitro keratinocyte culture techniques and the tissue engineering principles to human urothelium, to reconstruct an in vitro three-dimensional human bladder mucosa, suitable for grafting. MATERIAL AND METHODS Biopsy specimens of human bladder mucosa were obtained from patients undergoing suprapubic prostatectomy, in vitro cultured and finally, an immunohistochemical study was made. RESULTS A three-dimensional in vitro tissue was obtained, composed of a bio-artificial submucosa (fibrin gel and fibroblast) where the uroepithelial cells were seeding. We used a biodegradable polyglycolic acid mesh to facilitate the tissue manipulation and implantation. An immature epithelium was obtained with a weak immunostaining to cytokeratins. The immunohistochemical study could not demonstrate the development of basement membrane. CONCLUSIONS In vitro keratinocyte culture techniques could be applied to other epithelial tissues like the urothelium. We obtained a three-dimensional in vitro tissue suitable for grafting in a relatively short time, which needs the matrix interactions in order to mature.
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Chinnathambi S, Bickenbach JR. Human Skin and Gingival Keratinocytes Show Differential Regulation of Matrix Metalloproteinases When Combined With Fibroblasts in 3-Dimensional Cultures. J Periodontol 2005; 76:1072-83. [PMID: 16018749 DOI: 10.1902/jop.2005.76.7.1072] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Matrix metalloproteinases (MMP) and their inhibitors are expressed in tissues during interactions between keratinocytes and fibroblasts. Maintaining the balance between MMPs and their inhibitors is critical; failure to do so can lead to severe tissue damage or complete destruction, as seen in periodontal disease. Previously we showed that 3-dimensional (3-D) cultures of homotypically-combined skin and gingival cells mimicked the tissues in protein and lipid production, but heterotypic cultures did not. METHODS We examined the production and activation of MMPs in these homotypic and heterotypic combinations of skin and gingival keratinocytes and fibroblasts during the critical time that they reformed the tissues. Primary fibroblasts and keratinocytes were isolated from normal human gingiva and skin and grown in 3-D cultures for up to 42 days. MMP-1, MMP-2, and MMP-9 in the media and inhibition of MMPs from these cultures were analyzed. RESULTS These experiments determined that skin fibroblasts grown with skin or gingival keratinocytes secrete increased amounts of MMP-1 compared to gingival fibroblasts; that the interaction of keratinocytes with fibroblasts decreases the amount of MMP-2 produced by the fibroblasts in 3-D cultures; that skin keratinocytes, but not gingival keratinocytes, interact with fibroblasts to upregulate expression of the active form of MMP-9; and that medium conditioned by gingival 3-D cultures does not contain an inhibitor of MMP-9. CONCLUSION Varying the type of fibroblast beneath the keratinocytes allowed us to determine that skin and gingival keratinocytes differentially regulate the production and activation of MMP-9, but not MMP-2, a finding that could influence the success of tissue grafting after periodontal surgery.
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de Diego Rodríguez E, Villanueva Peña A, Roca Edreira A, Martín García B, Meana Infiesta A, Gómez Llames S, Gómez Román J. [Experimental study about viability of autologous free graft in vitro cultivated urinary epithelium]. Actas Urol Esp 2005; 28:714-31. [PMID: 15666514 DOI: 10.1016/s0210-4806(04)73173-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The purpose of this study is to apply the in vitro keratinocyte culture techniques and the tissue engineering principles to urothelium, to obtain a three-dimensional autologous tissue suitable for grafting. We also showed the viability of free graft cultured urothelium in an experimental model. MATERIAL AND METHODS An animal experimental model was designed to apply the techniques of cellular culture and tissue engineering. Biopsy specimens of bladder mucosa were obtained, in vitro cultured and posteriorly implanted in each animal. We established three groups based on different follow-up periods (7, 14 and 30 days), and made a final histomorphological study to demonstrate the viability of the graft at the end of its respective follow-up period. RESULTS A three-dimensional in vitro tissue was obtained, composed of a bio-artificial submucosa (fibrin gel and fibroblast) where the uroepithelial cells were seeding; a biodegradable polyglycolic acid mesh was used to facilitate the tissue manipulation and implantation. In the morphological study all the implants appeared viable, but the grafts with longer implantations periods were better conformed, showing a tisular structure with multiple cellular layers. CONCLUSIONS In vitro keratinocyte culture techniques could be applied to other epithelial tissues as the urothelium. We obtained a three-dimensional in vitro tissue suitable for grafting in a relatively short time. The histological study demonstrated that free autologous urothelial graft is totally viable, opening future clinics applications.
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Imaizumi F, Asahina I, Moriyama T, Ishii M, Omura K. Cultured mucosal cell sheet with a double layer of keratinocytes and fibroblasts on a collagen membrane. ACTA ACUST UNITED AC 2005; 10:657-64. [PMID: 15265283 DOI: 10.1089/1076327041348329] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of this study was to develop a novel cultured mucosal membrane that was facile to prepare and easy to handle, and that could be applied to mucosal defects in the oral cavity. Human oral keratinocytes and fibroblasts were prepared from the oral mucosa. We made the following two types of cultured mucosal cell sheets: a monolayer sheet of keratinocytes cultured on a collagen membrane (K-S) and a double-layered sheet of keratinocytes and fibroblasts on a collagen membrane (KF-S). A collagen membrane was used as a control. Each type of sheet was transplanted onto dorsal skin defects of nude mice. The wound area was measured for the assessment of wound contraction and a specimen was harvested for histologic evaluation 1 week and 4 weeks after grafting. Wound contraction was minimal with KF-S grafts. Although histologic examination showed normal differentiation of the epithelium in all graft types, the involucrin expression pattern of KFS was most similar to that of normal epithelium. These results indicate that a double-layered sheet of keratinocytes and fibroblasts cultured on a collagen membrane may facilitate epithelial healing and prevent wound contraction.
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Affiliation(s)
- Fumiko Imaizumi
- Oral Surgery, Department of Oral Restitution, Division of Oral Health Sciences, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
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Abstract
Tissue engineering is a field of research with interdisciplinary cooperation between clinicians, cell biologists, and materials research scientists. Many medical specialties apply tissue engineering techniques for the development of artificial replacement tissue. Stages of development extend from basic research and preclinical studies to clinical application. Despite numerous established tissue replacement methods in otorhinolaryngology, head and neck surgery, tissue engineering techniques opens up new ways for cell and tissue repair in this medical field. Autologous cartilage still remains the gold standard in plastic reconstructive surgery of the nose and external ear. The limited amount of patient cartilage obtainable for reconstructive head and neck surgery have rendered cartilage one of the most important targets for tissue engineering in head and neck surgery. Although successful in vitro generation of bioartificial cartilage is possible today, these transplants are affected by resorption after implantation into the patient. Replacement of bone in the facial or cranial region may be necessary after tumor resections, traumas, inflammations or in cases of malformations. Tissue engineering of bone could combine the advantages of autologous bone grafts with a minimal requirement for second interventions. Three different approaches are currently available for treating bone defects with the aid of tissue engineering: (1) matrix-based therapy, (2) factor-based therapy, and (3) cell-based therapy. All three treatment strategies can be used either alone or in combination for reconstruction or regeneration of bone. The use of respiratory epithelium generated in vitro is mainly indicated in reconstructive surgery of the trachea and larynx. Bioartificial respiratory epithelium could be used for functionalizing tracheal prostheses as well as direct epithelial coverage for scar prophylaxis after laser surgery of shorter stenoses. Before clinical application animal experiments have to prove feasability and safety of the different experimental protocols. All diseases accompanied by permanently reduced salivation are possible treatment targets for tissue engineering. Radiogenic xerostomia after radiotherapy of malignant head and neck tumors is of particular importance here due to the high number of affected patients. The number of new diseases is estimated to be over 500,000 cases worldwide. Causal treatment options for radiation-induced salivary gland damage are not yet available; thus, various study groups are currently investigating whether cell therapy concepts can be developed with tissue engineering methods. Tissue engineering opens up new ways to generate vital and functional transplants. Various basic problems have still to be solved before clinically applying in vitro fabricated tissue. Only a fraction of all somatic organ-specific cell types can be grown in sufficient amounts in vitro. The inadequate in vitro oxygen and nutrition supply is another limiting factor for the fabrication of complex tissues or organ systems. Tissue survival is doubtful after implantation, if its supply is not ensured by a capillary network.
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Affiliation(s)
- M Bücheler
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Bonn, Bonn, Germany.
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Izumi K, Feinberg SE, Iida A, Yoshizawa M. Intraoral grafting of an ex vivo produced oral mucosa equivalent: a preliminary report. Int J Oral Maxillofac Surg 2003; 32:188-97. [PMID: 12729781 DOI: 10.1054/ijom.2002.0365] [Citation(s) in RCA: 139] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The objective of this study was to assess the efficacy of the use of an ex vivo produced oral mucosa equivalent (EVPOME) for intraoral grafting procedures. Autogenous keratinocytes were harvested from a punch biopsy 4 weeks prior to surgery, placed in a serum-free culture system and seeded onto a human cadaveric dermal equivalent, AlloDerm. Thirty patients with either a premalignant or cancerous lesion were triaged into two groups, depending on the stage of disease: Group 1: EVPOME or Group 2: AlloDerm, control without an epithelial layer. Clinically, EVPOME grafts were easy to handle and showed excellent compliance on grafting. Both, EVPOME and AlloDerm grafts, showed a 100% take rate. At 6 days post-grafting, the EVPOME clinically showed changes indicating vascular ingrowth and had cytologic evidence of the persistence of grafted cultured keratinocytes on the surface. The EVPOME grafts had enhanced maturation of the underlying submucosal layer associated with rapid epithelial coverage when compared to the AlloDerm grafts at biopsies taken at 28 days post-grafting. In summary, EVPOME appears to be an acceptable oral mucosal substitute for human intraoral grafting procedures and results in a more favorable wound healing response than AlloDerm alone.
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Affiliation(s)
- K Izumi
- Department of Oral and Maxillofacial Surgery, Course for Oral Life Science, Niigata University Postgraduate School of Medical and Dental Sciences, Japan.
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Castro LNMD, Serricella P, Rodrigues AAF, Takiya CM, Silva ALD, Borojevic R. Uso da cultura de mucosa escamosa humana no tratamento de lesões jugais pré-cancerosas extensas. Rev Col Bras Cir 2002. [DOI: 10.1590/s0100-69912002000600005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJETIVO: Os autores propõem uma nova abordagem no tratamento de lesões extensas de natureza pré-cancerosa da mucosa jugal, utilizando enxerto de mucosa escamosa autógena cultivada em laboratório. MÉTODO: O enxerto é aplicado no mesmo tempo cirúrgico da ressecção da lesão original. Foram operados cinco pacientes, os quais receberam acompanhamento pós-operatório, sendo submetidos à biopsia de controle no 90º dia. A avaliação da integração do enxerto com o leito receptor foi realizada utilizando-se critérios clínicos e morfológicos, incluindo microscopia óptica e eletrônica. RESULTADOS: O estudo anatomopatológico com microscopia óptica e eletrônica dos cinco pacientes mostrou haver integração do enxerto da mucosa cultivada com o leito receptor. As células da mucosa cultivada formam camadas que se organizam e se diferenciam à semelhança da zona doadora. À microscopia eletrônica a mucosa enxertada apresentava lâmina basal com descontinuidades focais, presença de hemidesmosomas e fibrilas de ancoragem. CONCLUSÕES: Os resultados demonstraram que a técnica é oportuna e viável para o tratamento de lesões pré-cancerosas, outrora consideradas irressecáveis pela extensão e pode ser considerada uma possibilidade real para o tratamento cirúrgico definitivo das mesmas.
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Butler CE, Navarro FA, Park CS, Orgill DP. Regeneration of neomucosa using cell-seeded collagen-GAG matrices in athymic mice. Ann Plast Surg 2002; 48:298-304. [PMID: 11862036 DOI: 10.1097/00000637-200203000-00012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Tissue engineering of oral mucosa could allow improved reconstructive options for intraoral tissue defects. Porous collagen-glycosaminoglycan (CG) matrices coated with a silicone elastomer were seeded by centrifugation with cultured human oral mucosal epithelial cells (strain OKG4 gingival keratinocytes) at a density of 250,000 cells per square centimeter. Full-thickness dorsal wounds (1.5 x 1.5 cm) were created surgically on each athymic mouse and were treated with either a seeded matrix or an unseeded matrix, or they were left open as a control. The CG matrices reduced the degree of wound contraction at day 14 compared with open wounds. The epithelial thickness of seeded matrices at day 14 was significantly greater (p = 0.0001) than that of unseeded matrices. Seeded matrices had more rapid degradation at 14 days compared with unseeded matrices. Human oral mucosal cells seeded into CG matrices contribute to form a stratified and differentiated epithelial layer during revascularization, cellular infiltration, and degradation of the CG matrix.
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Affiliation(s)
- Charles E Butler
- Department of Plastic Surgery, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA
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Schlenz I, Korak KJ, Kunstfeld R, Vinzenz K, Plenk H, Holle J. The dermis-prelaminated scapula flap for reconstructions of the hard palate and the alveolar ridge: a clinical and histologic evaluation. Plast Reconstr Surg 2001; 108:1519-24; discussion 1525-6. [PMID: 11711921 DOI: 10.1097/00006534-200111000-00012] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Ideal reconstructions of complex defects in the midface require the restitution not only of bone and soft tissue, but also of a thin and durable lining of the oral cavity. So far, split-thickness skin grafts, intestinal grafts, and in vitro cultured mucosal grafts have been used for the reconstruction of the oral lining. The use of skin as a substitute for oral mucosa is controversial because contraction, hair growth, maceration, and dysplastic changes can occur. This clinical and histologic study was performed to evaluate the suitability of dermis as a substitute for oral lining. Twelve complex defects of the midface were reconstructed with dermis-prelaminated scapula flaps. A bony flap from the lateral border of the scapula was prepared, and osseointegrated implants were placed. The bone flap was then prelaminated with dermis and covered with a Gore-Tex membrane to prevent adhesions. The composite flap was transferred to the midface 2 to 3 months later. The oral lining of the flap was evaluated clinically and histologically at 2, 4, and 6 weeks and at 3 to 41 months after the reconstruction. In all patients, the reconstructed bone was covered with a thin and lubricated surface without hair growth. None of the patients showed any signs of maceration. Histologically, these findings corresponded to a keratinized stratified squamous epithelium with highly developed connective-tissue papillae. These features closely resemble those of the normal mucosa of the hard palate and the gingiva. Thus, dermis prelamination is an effective method for reconstructing the mucosa of the alveolar ridge and the hard palate.
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Affiliation(s)
- I Schlenz
- Department of Plastic and Reconstructive Surgery, Wilhelminenspital, Vienna, Austria.
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van Laarhoven CJ, Andriesse GI, Back WA, Schipper ME, Akkermans LM, van Vroonhoven TJ, Gooszen HG. The ileo neorectal anastomosis: an experimental study on development of the surgical technique and theoretical background. Colorectal Dis 2001; 3:82-94. [PMID: 12791000 DOI: 10.1046/j.1463-1318.2001.00179.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE The keystones of surgical treatment of ulcerative colitis and familial adenomatous polyposis are resection of the diseased colon with either an ileostomy or restoration of oro-anal continuity with an ileo-anal pouch. The ileo pouch anal anastomosis however, has a 15-35% pouch-related complication rate, 10% failure rate and is accompanied by an unpredictable functional outcome. In order to reduce these unfavourable rates and to improve functional results an alternative surgical technique, the ileo neorectal anastomosis (INRA), was developed experimentally. MATERIALS AND METHODS In an experimental study 12 Yorkshire-Dutch landpigs had a subtotal colectomy and rectal mucosectomy. Subsequently a vascularized ileal mucosa sling was created and transposed on to the denuded rectal muscular cuff in eight. In another four animals a non-vascularized mucosa sling was transposed. The covering ileostomy was closed after 3 weeks. Repeated endoscopies, histological examinations of mucosal biopsies and rectal compliance measurements were carried out to evaluate the functional result of the neorectum. RESULTS The surgical procedure of the INRA was technically successful in this animal study. Repeated endoscopy and histology showed complete ileal mucosa ingrowth in the neorectum without severe fibrosis in the group of animals with a vascularized sling. At follow up after 1 year no colonic metaplasia had occurred. Measurements of the neorectal reservoirs in the group of animals with a vascularized INRA procedure showed a median 'maximum tolerated volume' of 338 ml (range 300-410 ml). CONCLUSION The INRA is technically feasible and reproducible. The histologically proven survival of the vascularized ileal mucosa and development of a compliant neorectal reservoir make the INRA an interesting alternative restorative procedure. Avoidance of the pouch-related complications of the ileo pouch anal anastomosis by this procedure might herald a new era of restorative surgery.
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Affiliation(s)
- C J van Laarhoven
- Department of Surgery, University Medical Centre Utrecht, The Netherlands.
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Lauer G, Schimming R. Tissue-engineered mucosa graft for reconstruction of the intraoral lining after freeing of the tongue: a clinical and immunohistologic study. J Oral Maxillofac Surg 2001; 59:169-75; discussion 175-7. [PMID: 11213985 DOI: 10.1053/joms.2001.20489] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE This article describes the use of tissue-engineered mucosal grafts instead of split-thickness skin grafts after freeing of the tongue in patients who had previous resection of an oral squamous cell carcinoma and initial primary wound closure. PATIENTS AND METHODS Tissue-engineered mucosal grafts, up to 75 cm2 in size, were cultured from biopsy specimens of the hard palate in 6 patients, starting 3 to 4 weeks before the operation. After freeing of the tongue, the engineered mucosa was implanted on the wound surface by using vaseline gauze as carrier and fixed with an intraoral gauze wound dressing. RESULTS A good glossoalveolar sulcus was formed in 5 patients, resulting in good mobility of the tongue and a satisfactory denture-bearing surface. In 1 patient, there was a disturbance of wound healing, leading to severe shrinkage of the glossoalveolar sulcus and very limited improvement in tongue mobility. Preoperative bromodeoxyuridine (BrdU) labeling of the graft and postoperative immunohistochemical staining of biopsy specimens from the grafted areas with anti-BrdU showed that the cultured cells are integrated into the newly formed mucosal epithelium. Postoperative histologic investigations showed a differentiation process in the grafted mucosal epithelium, with a change in the expression of cytokeratins. At 6 months postoperatively, the typical pattern of normal nongrafted mucosa was regained. CONCLUSIONS This investigation provides evidence that tissue-engineered mucosal cells can serve as a graft for large intraoral wounds. Complete intraoral lining is quickly reestablished, and normal epithelial differentiation is seen in the graft area within a 6-month postoperative period.
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Affiliation(s)
- G Lauer
- Department of Oral and Maxillofacial Surgery, University of Freiburg, Germany.
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Izumi K, Terashi H, Marcelo CL, Feinberg SE. Development and characterization of a tissue-engineered human oral mucosa equivalent produced in a serum-free culture system. J Dent Res 2000; 79:798-805. [PMID: 10765951 DOI: 10.1177/00220345000790030301] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A problem maxillofacial surgeons face is a lack of sufficient autogenous oral mucosa for reconstruction of the oral cavity. Split-thickness or oral mucosa grafts require more than one surgical procedure and can result in donor site morbidity. Skin has disadvantages of adnexal structures and a different keratinization pattern than oral mucosa. In this study, we successfully assembled, ex vivo, a human oral mucosa equivalent, consisting of epidermal and dermal components, in a defined, essential-fatty-acid-deficient, serum-free culture medium without a feeder layer, that could be used for intra-oral grafting in humans. Autogenous oral keratinocytes were seeded onto a cadaveric dermis, AlloDerm. The oral mucosa equivalent was cultured at an air-liquid interface for 2 wks. The resulting equivalent had a well-stratified parakeratinized epithelial layer similar to native oral keratinized mucosa. Expression of differentiation markers, filaggrin and cytokeratin 10/13, suggested a premature keratinized state. The presence of proliferation markers, proliferating cell nuclear antigen (PCNA) and Ki-67, suggested a state of hyperproliferation. Fatty acid composition of the equivalent was similar to that of in vitro cultured oral keratinocytes but differed from the that of in vivo native tissue, showing a lower content of 18:2 and 20:4, and a higher content of 16:1 and 18:1 fatty acids, respectively. The keratinocytes of the equivalent appeared to be in a more active and proliferative state than native keratinized mucosa. The dynamic nature of the cell population on the oral mucosa equivalent may be beneficial for intra-oral grafting procedures and for transfection of the keratinocytes.
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Affiliation(s)
- K Izumi
- Dept. of Oral and Maxillofacial Surgery, University of Michigan School of Dentistry, Medical Center, Ann Arbor 48109-0018, USA
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Cho KH, Ahn HT, Park KC, Chung JH, Kim SW, Sung MW, Kim KH, Chung PH, Eun HC, Youn JI. Reconstruction of human hard-palate mucosal epithelium on de-epidermized dermis. J Dermatol Sci 2000; 22:117-24. [PMID: 10674825 DOI: 10.1016/s0923-1811(99)00056-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Artificial hard-palate mucosa equivalents were reconstructed using keratinocytes derived from normal human hard-palate and de-epidermized dermis. Reconstructed hard-palate mucosal epithelium formed in three-dimensional culture was compared to native hard-palate mucosal epithelium and reconstructed oral buccal mucosal epithelium with regard to keratin expression. Artificial hard-palate mucosal epithelium reconstructed in medium with delipidized serum showed a differentiation pattern similar to that of hard-palate epithelium in vivo. The present study also confirmed that keratinocytes derived from hard-palate mucosa are intrinsically different from those of nonkeratinizing oral surfaces.
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Affiliation(s)
- K H Cho
- Department of Dermatology, Seoul National University College of Medicine, Seoul National University Hospital, South Korea.
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Izumi K, Takacs G, Terashi H, Feinberg SE. Ex vivo development of a composite human oral mucosal equivalent. J Oral Maxillofac Surg 1999; 57:571-7; discussion 577-8. [PMID: 10319831 DOI: 10.1016/s0278-2391(99)90077-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE The aim of this study was the ex vivo development of a composite oral mucosal equivalent composed of a continuous stratified layer of human oral keratinocytes grown on a cadaveric human dermal matrix in a defined medium without a feeder layer. MATERIALS AND METHODS Enzymatically dissociated human oral keratinocytes from keratinized oral mucosa were cultured, submerged in a serum-free, low-calcium (0.15 mmol/L) supplemented medium, and expanded through several passages. Once a sufficient population of keratinocytes was reached, they were seeded on 1-cm2 pieces of AlloDerm (LifeCell Co, Woodlands, TX), an acellular nonimmunogenic cadaveric human dermis, at cell densities of 2.5 X 10(4), 5.0 X 10(4), 1.25 X 10(5), or 2.5 X 10(5). The oral keratinocyte-AlloDerm composites were cultured while submerged in a high-calcium (1.8 mmol/L) medium for 4 days. After 4 days, the composites were raised to an air-liquid interface. Samples of the composites were taken for histologic examination at 4, 11, and 18 days postseeding of the keratinocytes on the AlloDerm. RESULTS At day 4, only the seeded cell density of 2.5 X 10(5) cells/cm2 formed a continuous monolayer on the AlloDerm. At day 11, a continuous stratified epithelium was seen, and at day 18 a well-differentiated, confluent parakeratotic epithelial layer was developed at cell densities of 5.0 X 10(4), 1.25 X 10(5), and 2.5 X 10(5)cells/cm2. CONCLUSION With the method used, it was possible to successfully develop an ex vivo composite oral mucosal equivalent that consisted of a stratified epidermis on a dermal matrix.
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Affiliation(s)
- K Izumi
- Section of Oral and Maxillofacial Surgery, University of Michigan School of Dentistry, Ann Arbor, USA
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20
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Omura S, Mizuki N, Horimoto S, Kawabe R, Fujita K. A newly developed collagen/silicone bilayer membrane as a mucosal substitute: a preliminary report. Br J Oral Maxillofac Surg 1997; 35:85-91. [PMID: 9146864 DOI: 10.1016/s0266-4356(97)90681-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A new bilayer membrane proved effective as a mucosal substitute. The membrane is composed of an outer layer of silicone and an inner layer of dehydrothermally cross linked composites of fibrillar and denatured collagen sponge. The membrane was placed on oral mucosal defects of five patients after operations for cancer. Ten to 14 days after application the outer silicone sheet was removed, leaving only the inner collagen sponge layer into which cellular tufts of fibroblasts and capillaries had infiltrated. The infiltrated collagen matrix became a new connective tissue that epithelialised rapidly by migration of peripheral epithelium 4-5 weeks after application. In all cases the postoperative course was unremarkable and the repair was effective.
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Affiliation(s)
- S Omura
- Department of Oral and Maxillofacial Surgery, School of Medicine Yokohama City University, Japan
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21
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Ross UH, Wittmann G. Living epithelial-mesenchymal compounds formed in vitro suitable for autografting. Eur Arch Otorhinolaryngol 1997; 254 Suppl 1:S12-7. [PMID: 9065616 DOI: 10.1007/bf02439712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Three different, human epithelial-mesenchymal compounds (EMC) were generated in vitro for prospective grafting in epithelial defects. All compounds consisted of a fibroblast-populated collagen lattice as a mesenchymal component seeded with different types of cultured epithelial cells isolated from biopsies of healthy skin, oral mucosa and respiratory mucosa. Maturation of the epithelial cells was enabled by the presence of a high calcium concentration (1.8 mM) when cultures were lifted to the air-liquid interface. Light and electron microscopy revealed moderate differentiation of the multilayered epithelium in all compounds as well as basement membrane development at the epithelial-mesenchymal junction after 2-3 weeks. A coherent, tissue-like consistency of the collagen lattice and the presence of a basement membrane preventing detachment of the epithelium permitted easy handling and even loose suturing of the compounds produced.
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Affiliation(s)
- U H Ross
- Department of Oto-Rhino-Laryngology, University of Freiburg, Germany
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22
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Sugimura Y, Hata K, Torii S, Ueda M. Transplantation of cultured mucosal epithelium: an experimental study. J Craniomaxillofac Surg 1996; 24:352-9. [PMID: 9032603 DOI: 10.1016/s1010-5182(96)80036-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We investigated morphological changes after transplantation of cultured mucosal epithelium using a modified Barrandon's method (1988). Serially cultivated human mucosal epithelium was transplanted onto the reverse side of rectangular dorsal skin flaps in hairless mice. The morphological changes in the epithelium were studied using paraffin sections. The modified Barrandon's method used in this study has advantages such as minimum external trauma and less chance of infection. The cultured epithelium was taken within 1 week and gradually increased its epithelial thickness. Keratinized epithelium arises after 3 weeks. At 4 weeks after grafting, the grafted epithelium comprised 7-10 cell layers. The structure of transplanted tissue, in conjunction with surrounding connective tissues, showed dermis-like features at day 7 after transplantation. From these results, it was confirmed that cultured mucosal epithelium could be successfully transplanted and its morphology was similar to that of normal mucosal tissue.
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Affiliation(s)
- Y Sugimura
- Department of Oral Surgery, Nagoya University, School of Medicine, Japan
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Formanek M, Millesi W, Willheim M, Scheiner O, Kornfehl J. Optimized growth medium for primary culture of human oral keratinocytes. Int J Oral Maxillofac Surg 1996; 25:157-60. [PMID: 8727592 DOI: 10.1016/s0901-5027(96)80064-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The effect of different media additives in defining optimal growth conditions for primary cultures of human oral keratinocytes was studied. A cocultivation technique with irradiated Swiss-3T3-fibroblasts in 96-well plates enables the comparison of additives for primary keratinocyte cultures derived from one patient. 3H-labeled thymidine uptake showed no growth or growth inhibition with adenine, choleratoxin or transferrin compared to basal medium (Dulbecco's modified Eagle's medium (DMEM) and 10% fetal calf serum). Among single additives, 5 micrograms/ml hydrocortisone, 5 micrograms/ml insulin, 10 ng/ml EGF, 2 micrograms/ml bovine pituitary extract, and 10(-9) M triiodothyronine showed the greatest capacity to promote keratinocyte growth. With all possible combinations of additives, maximum stimulation was found with a combination of EGF (10 ng/ml), insulin (5 micrograms/ml), and hydrocortisone (5 micrograms/ml); none of the other combinations were more effective. Our data indicate that in short-term cultures (up to 5 days) various media additives described in the literature are not necessarily required in this system of primary culture of human oral keratinocytes.
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Affiliation(s)
- M Formanek
- Department of Otorhinolaryngology, General Hospital, University of Vienna, Austria
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Kuroyanagi Y. Materials preparation and artificial skin graft. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 1994. [DOI: 10.1016/0928-4931(94)90044-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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