Bone Tissue Engineering for Tempero Mandibular Joint Application

颞下颌关节(TMJ)是一个铰链状的关节，连接着下颌骨和颅骨的颞骨。TMJ由两部分组成：软组织和骨组织。颞下颌关节紊乱病(TMD‘s)是指影响整个或部分关节的与TMJ有关的问题或状况。TMD影响了全球约1050万成年人，占英国总人口的25%。目前的外科手术包括：关节穿刺术(将针插入上颌腔，注入溶液以疏松关节，冲洗掉任何微小颗粒)、关节镜术(在耳朵前面做一个小切口，使用器械移除任何炎症组织或重新调整颌骨)、开放关节手术(修复、调整或移除关节盘)和全关节置换术。骨组织工程是一个涉及生物材料和细胞治疗的过程，它们共同作用于再生因各种原因(如受伤或疾病)而丢失的骨和组织。水凝胶是一种三维聚合物网络，它被交联以产生具有较大水分含量的基质。除了水凝胶，生物活性玻璃也被认为是一种合适的支架材料，由二氧化硅、钠、钙和磷氧化物组成。以前在这一领域的研究主要基于关节盘的再生，因为这是由于关节盘移位和退行性变的高比率而导致的大多数颞下颌关节紊乱症的常见成分。TMJ的骨组织工程在临床上是有必要的，因为目前的技术成本效益不高，最重要的是不能长期使用。由于TMJ是无血管性质的，骨和组织再生以替代的目的是在这一研究领域使用的最可靠的技术。该项目旨在通过使用新技术的骨组织工程来再生这个复杂的骨软骨关节(下颌骨)，这在更广泛的临床范围内可能会将手术风险降至最低，限制停机时间-使其对患者来说是一种更安全的体验。在选择生物材料时，将仔细考虑以下重要因素：执行所需任务的合适细胞类型、正确的环境(通过仔细选择水凝胶/生物活性玻璃)、适合生长因子的生物分子以及影响细胞发育的适当物理和机械力。3D发现进化将被用于生物打印。这是一种新的设备，以前没有在任何与TMJ再生有关的研究中使用过。这款机器提供了模块化、灵活性和定制化，这些都是重要的因素。

The temporomandibular joint (TMJ) is a hinge like joint that connects the mandible to the temporal bone of the skull. The TMJ consists of two components; soft and bony tissue. Temporomandibular disorders (TMD's) refer to problems or conditions related to the TMJ which affect the whole or part of the joint. TMD's affect around 10.5 million adults worldwide and 25% of the overall UK population. Surgical procedures currently include: arthrocentesis (needles inserted into upper jaw cavity and a solution is injected to loosen up the joint and wash out any microscopic particles), arthroscopy (a small incision is made in front of the ear and an instrument is used to remove any inflamed tissue or to realign the jaw), open joint surgery (repairs, realigns or removes articular disc) and total joint replacement. Bone tissue engineering is a process which involves biomaterials and cell therapy which work together to regenerate bone and tissue that is lost due to various reasons such as injury or disease. Hydrogels are three-dimensional polymer networks that are crosslinked to create matrices with large water content. As well as hydrogels, bioactive glasses are also considered as a suitable material for scaffolds and are composed of silica, sodium, calcium and phosphate oxides. Previous studies in this area have heavily been based on the regeneration of the articular disc as this is the component that is commonly associated with the majority of temporomandibular disorders due to high rates of disc displacement and degeneration. There is a clinical need for bone tissue engineering of the TMJ as current techniques are not cost efficient and most importantly not successful for long term purposes. As the TMJ is of an avascular nature, bone and tissue regeneration for replacement purposes is the most credible technique to use in this research area. This project aims to regenerate this complex osteochondral joint (lower mandible) through bone tissue engineering using novel techniques, which on a wider clinical scope could potentially minimise the surgical risks, limit the downtime-making it a safer experience for the patient. The following important factors will be carefully considered when selecting the biomaterials: the suitable cell type to carry out the required task, the correct environment (through careful selection of the hydrogel/bioactive glass), the right biomolecules for growth factors and the suitable physical and mechanical forces to influence the development of cells. The 3D Discovery Evolution will be used for bio-printing. This is a novel piece of equipment that has not been used in any previous studies relating to the regeneration of the TMJ. The machine offers modularity, flexibility and customisation which are all important factors.