全新视角透视口腔黏膜组织工程

口腔黏膜组织工程主要应用于修复因肿瘤切除、牙周病、外伤等导致的软组织缺损。以前的组织工程研究主要围绕上皮细胞培养方法的发展以及结缔组织支架材料的研发开展，本文将对121腔黏膜组织工程替代物的培养模式、支架结构、基质功能及临床应用进行综述，展示组织工程的新视角及口腔黏膜组织工程的新应用。     

以胶原膜为支架构建组织工程化人口腔黏膜研究

目的：应用组织工程技术,以胶原膜为支架构建组织工程化人口腔黏膜。方法：体外培养、扩增人口腔黏膜角化细胞,通过细胞形态学及角蛋白免疫组化染色等对细胞进行定性研究,角化细胞接种于胶原膜上液面下培养1周后,升至液-气平面培养1周,光镜、电镜下观察大体组织形态及超微结构。结果：口腔黏膜上皮细胞可在生物支架材料胶原膜上粘附生长,并可形成上皮样组织,但无成熟的桥粒及基底膜样结构。胶原膜降解快,14d左右难以操作。结论：胶原膜与口腔黏膜角化细胞具有良好的生物相容性;由于降解速度和不易操作等特点,胶原膜作为支架材料构建组织工程化口腔黏膜有待深入研究。     

口腔黏膜组织工程的研究

近年来国内外许多学者致力于口腔黏膜组织工程的研究 ,取得了相应的成绩。该文即从口腔黏膜组织工程的支架材料以及临床应用情况进行简要综述     

组织工程化口腔黏膜支架材料的研究进展

随着组织工程技术的发展,近年来国内外许多学者致力于口腔黏膜组织工程的研究,取得了一定的成就,支架材料是黏膜组织工程的一个重要因素,本文对组织工程化口腔黏膜的支架材料研究作一简要综述。     

小肠黏膜下层修复骨组织缺损的研究进展

天然支架材料能够引出宿主组织反应来发动血管形成,促进组织沉积,重塑结构和功能.文章综述了作为组织工程支架材料的小肠黏膜下层修复骨组织缺损的现状,展望了其在口腔领域的应用前景.     

用PGA支架体外构建人口腔黏膜固有层的实验研究

目的:探讨利用可吸收生物材料聚羟基乙酸(polyglycolicacids,PGA)和口腔黏膜成纤维细胞(oralfibroblast,OFC)在体外构建组织工程化口腔黏膜固有层的可能性。方法:取细胞经体外培养,扩增至第3代,与PGA混合培养,形成细胞—生物材料复合物,每2d换液一次。动态观察细胞形态和粘附生长状况,于体外培养1周左右,取组织作电镜观察、组织学和RT-PCR检测。结果:复合物体外培养6d,OFC粘附在生物支架上,沿PGA纤维纵轴方向向两极伸展,细胞分泌基质并形成拉网状结构。HE染色和Masson染色均提示胶原纤维形成,RT-PCR显示胶原成分主要为Ⅰ型胶原。结论:应用PGA支架可以在体外成功构建口腔黏膜固有层组织。     

组织工程化口腔黏膜应用研究进展

目的组织工程是应用细胞生物学和工程学原理,将少量种子细胞经体外扩增后与可降解生物材料复合,用于替代或修复病变、缺损组织,重建生理功能。组织工程化口腔黏膜是目前研究的热点,可用于临床,也可用于体外生物相容性、黏膜刺激物、疾病及口腔生物学的实验研究。本文就组织工程化口腔黏膜的构建和主要应用作一综述。     

以胚鼠脱细胞真皮构建口腔黏膜固有层的实验研究

目的:探讨以胚鼠脱细胞真皮构建组织工程化口腔黏膜固有层的可行性。方法:取胚鼠皮肤制备脱细胞真皮支架,将体外培养的人口腔黏膜成纤维细胞复合入胚鼠脱细胞真皮支架中,分别于接种后的1、4、7 d行HE染色、荧光显微镜及电镜检测。结果:胚鼠脱细胞真皮支架行HE染色显示未见细胞残留,表皮-真皮结合面保存波浪状基底膜样结构,HE、荧光显微镜及电镜检测均显示成纤维细胞复合入胚鼠脱细胞真皮支架后可黏附、生长、增殖。结论:以胚鼠脱细胞真皮体外构建的口腔黏膜固有层具有较好的组织构架,为进一步研究成纤维细胞-上皮细胞相互作用机制和构建全层口腔黏膜提供良好的实验模型。     

不同支架材料对义齿主承托区黏膜表面细菌粘附影响的研究

目的比较3种不同金属支架对口腔黏膜表面细菌粘附的影响。方法选择肯氏Ⅰ类牙列缺损患者50例,BPD支架(13例)、Vitallium 2000支架(15例)、及纯钛支架(22例)修复。进行患者修复前及修复后3个月口腔黏膜表面菌斑的采集,接种和培养,计算菌落数(cfu/m L),统计学分析。结果同一种金属支架修复3个月,口腔黏膜表面G+球菌、G+杆菌、G-球菌及G-杆菌的粘附数量均较支架戴用前明显增加,差异具有统计学意义(P<0.05);BPD支架和Vitallium 2000支架戴用后口腔黏膜表面细菌粘附数量较纯钛支架戴用后多,差异具有统计学意义(P<0.05)。结论 3种金属支架戴用后均易导致口腔黏膜表面细菌附着;与BPD支架、Vitallium 2000支架相比,纯钛金属支架细菌在口腔黏膜表面的粘附少。     

三维组织工程化口腔黏膜体外构建研究

目的　探讨以脱细胞异体真皮基质（acellular dermal matrix,ADM）为生物支架,体外构建三维组织工程化口腔黏膜（tissue-engineered mucosa,TEM）的可行性。方法　选择10例患者第三磨牙拔除时切除的龈瓣,每块大小1.0 cm × 0.5 cm。利用组织块法结合胰蛋白酶消化法体外培养、分离口腔黏膜上皮细胞和成纤维细胞。以ADM为生物支架,先将成纤维细胞按1 × 106个/mL密度接种于支架上,培养1周后再将上皮细胞按同密度接种于支架上,继续培养1周后,将支架移至气-液平面培养1周。HE染色及免疫组化染色观察TEM体外构建情况。结果　     eHE染色显示,构建的TEM含有类上皮层和固有层,其中上皮层细胞分化层次较好,固有层细胞层次不清。免疫组化染色显示,TEM上皮层和固有层中的标志蛋白均呈阳性表达。结论　在体外可以构建出组织结构类似口腔黏膜的三维TEM。     

Tissue-engineered oral mucosa

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.     

In vitro and in vivo cytokeratin patterns of expression in bioengineered human periodontal mucosa

Background and Objective:  Development of human oral mucosa substitutes by tissue engineering may provide new therapeutic tools for the management of periodontal diseases. In this study we evaluated a fibrin–agarose human oral mucosa substitute both in vitro and in vivo .
Material and Methods:  In vitro bioengineered oral mucosa substitutes were developed from irrelevant biopsy samples of human oral gingiva. In vivo evaluation of the constructed tissues was performed by implantation into athymic nude mice. The expression of several epithelial markers was assessed by microarray analysis and immunohistochemistry.
Results:  Bioengineered oral mucosa samples kept in vitro developed a multilayered epithelium that expressed several cytokeratins, including some markers of simple epithelia (cytokeratins 7, 8 and 18), along with markers of stratified epithelia (cytokeratins 5 and 13) and of cell proliferation (proliferating cell nuclear antigen). Bioengineered tissues grafted in vivo onto nude mice exhibited very good biointegration with the host, showing a cytokeratin expression pattern that was very similar to that of normal native oral mucosa controls. Histological analysis of the artificial tissues demonstrated that oral mucosa substitutes evaluated in vivo were structurally mature, showing some typical structures of human native oral mucosa such as rete ridges and chorial papillae, along with numerous blood vessels at the fibrin–agarose stromal substitute. These structures were absent in samples evaluated in vitro .
Conclusion:  The results indicate that this model of human oral mucosa, constructed using fibrin–agarose scaffolds, shows similarities to native oral mucosa controls and imply that bioengineered oral mucosa substitutes could eventually be used clinically.     

口腔黏膜上皮细胞及成纤维细胞与PGA的生物相容性研究

目的：观察口腔黏膜上皮细胞与成纤维细胞在聚羟基乙酸(PGA)上的粘附生长情况，在体外形成活的黏膜样组织的能力。方法：口腔黏膜上皮细胞无血清、无饲养层体外培养、扩增至第二代，与PGA混合培养形成细胞一生物材料复合物；口腔黏膜成纤维细胞体外培养、扩增至第二代，与PGA混合培养形成细胞一生物材料复合物；①光镜、扫描电镜下观察两种细胞分别与PGA的粘附生长情况；②用MTT法检测口腔黏膜上皮细胞及成纤维细胞在PGA上的增殖情况，绘制细胞生长曲线。结果：口腔黏膜上皮细胞与成纤维细胞能够在PGA上粘附生长，其生长增殖能力优于平皿培养。结论：PGA与口腔黏膜上皮细胞或成纤维细胞具有良好的生物相容性，其降解产物无毒。不影响细胞生长及分泌基质。     

Tissue-engineered oral mucosa: a review of the scientific literature

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.     

Non-epithelial oral mucosal progenitor cell populations

This review considers the potential existence and role of stem or progenitor cell populations within the non-epithelial tissues of the oral mucosa. Currently, there is little published evidence supporting this hypothesis; however, because of the similarities in structure and function of the oral mucosa and skin, findings within the dermis of the skin may potentially reflect the situation within the oral mucosa. Over recent years, the identification of the skin as a local reservoir of adult stem cell populations and the idea that multipotent cell populations exist within the dermal tissues of skin has gained increasing credibility. Indeed, numerous multipotent progenitor cells have been identified within the dermis and resident appendages, all capable of differentiating into multiple cell lineages. Furthermore, a number of these cell populations have been implicated in the repair of these tissues following injury. There is increasing evidence suggesting that such populations of progenitor cells may also reside within the lamina propria. In this respect, the ability to isolate large numbers of multipotent progenitor cells from a tissue which when biopsied heals without a scar would be of great interest scientifically and commercially, particularly with respect to future therapeutic applications and the developing discipline of tissue engineering.     

Tissue engineering: state of the art in oral rehabilitation

Summary  More than 85% of the global population requires repair or replacement of a craniofacial structure. These defects range from simple tooth decay to radical oncologic craniofacial resection. Regeneration of oral and craniofacial tissues presents a formidable challenge that requires synthesis of basic science, clinical science and engineering technology. Identification of appropriate scaffolds, cell sources and spatial and temporal signals (the tissue engineering triad) is necessary to optimize development of a single tissue, hybrid organ or interface. Furthermore, combining the understanding of the interactions between molecules of the extracellular matrix and attached cells with an understanding of the gene expression needed to induce differentiation and tissue growth will provide the design basis for translating basic science into rationally developed components of this tissue engineering triad. Dental tissue engineers are interested in regeneration of teeth, oral mucosa, salivary glands, bone and periodontium. Many of these oral structures are hybrid tissues. For example, engineering the periodontium requires growth of alveolar bone, cementum and the periodontal ligament. Recapitulation of biological development of hybrid tissues and interfaces presents a challenge that exceeds that of engineering just a single tissue. Advances made in dental interface engineering will allow these tissues to serve as model systems for engineering other tissues or organs of the body. This review will begin by covering basic tissue engineering principles and strategic design of functional biomaterials. We will then explore the impact of biomaterials design on the status of craniofacial tissue engineering and current challenges and opportunities in dental tissue engineering.     

Tissue engineering for periodontal regeneration

As a result of periodontal regeneration research, a series of clinical techniques have emerged that permit tissue engineering to be performed for more efficient regeneration and repair of periodontal defects and improved implant site development. Historically, periodontal regeneration research has focused on a quest for "magic filler" material. This search has led to the development of techniques utilizing autologous bone and bone marrow, allografts, xenografts, and various man-made bone substitutes. Though these techniques have had limited success, the desire for a more effective regenerative approach has resulted in the development of tissue engineering techniques. Tissue engineering is a relatively new field of reconstructive biology which utilizes mechanical, cellular, or biologic mediators to facilitate reconstruction/regeneration of a particular tissue. In periodontology, the concept of tissue engineering had its beginnings with guided tissue regeneration, a mechanical approach utilizing nonresorbable membranes to obtain regeneration in defects. In dental implantology, guided bone regeneration membranes +/- mechanical support are used for bone augmentation of proposed implant placement sites. With the availability of partially purified protein mixture from developing teeth and growth factors from recombinant technology, a new era of tissue engineering whereby biologic mediators can be used for periodontal regeneration. The advantage of recombinant growth factors is this tissue engineering device is consistent in its regenerative capacity, and variations in regenerative response are due to individual healing response and/or poor surgical techniques. In this article, the authors review how tissue engineering has advanced and discuss its impact on the clinical management of both periodontal and osseous defects in preparation for implant placement. An understanding of these new tissue engineering techniques is essential for comprehending today's ever-expanding oral plastic surgery procedures.