Phosphate Bio-mineral-Ultrafast Laser interaction - a pathway for future hard tissue re-engineering (Novel Tool for Surgical technologies) - LUMIN

尤其是由于摄入食物和饮料造成的酸蚀，以及由于牙列的普遍磨损而造成的牙齿表面损失，是一个全球性的问题。牙齿表面釉质的持续侵蚀和丢失会导致过敏。这种口腔疾病在儿童和社会老龄化人口中都很严重，并可能对生活质量产生重大影响。2011年的人口普查指出，英格兰和北爱尔兰有16.3%的人口年龄在65岁以上(《每日电讯报》2012年7月17日)，这表明遭受酸侵蚀的人数在未来几年可能会继续上升。这意味着更迫切地需要提供一种强大的解决方案来修复丢失的牙釉质，这一问题仍然是临床牙科的难题。为了解决这个问题，我们建议研究一种工程方法，在牙齿上喷洒一层薄的矿物层，然后使用超快激光照射脉冲将其致密并结合到下面的牙齿上。跨学科的Lumin项目将开发和利用任务(A)中的微喷嘴生物矿物输送技术及其随后使用飞秒脉冲(FSP)激光进行烧结的技术，以修复酸蚀的牙釉质。拟议的FSP激光器的工作波长将在近红外(1500-2100纳米)的人眼安全区域内，并将通过设计激光腔在能量/功率传输方面提供灵活性，这是任务(B)的主要目标。正如上文目标部分所述，任务(B)的另一个目标是将任务(A)的微喷嘴生物矿物输送系统与单一平台上的激光相结合，以便在酸蚀的釉质表面上实现沉积的生物矿物层的快速烧结。在这项研究中，将为任务(A)中的微喷嘴输送设计和优化晶体和凝胶形式的新型耐酸釉质矿物替代品。材料输送系统与FSP-激光器的集成将产生同步烧结。因此，这里的工程方法将产生3种不同的平台技术用于未来的开发，这将在利兹组织工程和医疗技术综合知识中心的支持下实现。我们将调查在FSP激光下对凝胶和悬浮液材料使用微喷嘴是否会由于纳米颗粒的产生和释放而造成毒性风险(一些人可能会认为这些颗粒可能会被FSP激光的强光敏化)。因此，在任务(C)中，我们将评估任何纳米颗粒和光诱导的毒性，并进行风险分析。这将符合标准的临床程序，目的是识别并将任何迫在眉睫的风险降至最低。在任务(C)之后，我们在任务(D)中的目标是实施任务(A)和(B)中开发的工程方法，以及任务(C)中的风险缓解策略，以使用原位口腔矫治器试验来测试口腔环境中的FSP激光烧结牙釉质矿物，这是利兹牙科研究所首创的一项技术，旨在将广泛的体内试验中的风险降至最低。在任务(D)中，将利用材料科学、工程和临床牙科领域的学术专业知识，对烧结材料进行酸侵蚀、耐久性、硬度、韧性和弯曲特性的测试。IKC团队将通过Graeme Howling博士的专业知识提供支持，首先通过项目合作伙伴M-Squared Laser、British Glass和Giltec开发技术开发。该项目还旨在与海外学术机构建立学术联系，例如利哈伊的IMI和宾夕法尼亚州立大学的材料科学，以及通过SUPA牵头的EPSRC资助的合作与美国的斯坦福大学和Caltec建立学术联系。工业界和学术界与英国的Photonics KTN的联系也有望在项目过程中得到发展。

Acid erosion due to food and drink intake in particular and tooth surface loss due to general wear of the dentition is a global problem. Continual erosion and loss of the surface enamel of the tooth leads to hypersensitivity. This oral condition is acute in both children and the ageing population of society and can have a significant impact on the quality of life. The 2011 census points out that 16.3% of the population of England and N Ireland is above 65 years old (Daily Telegraph 17 July 2012), which suggests that the number of people suffering from acid erosion may continue to rise in years to come. This means that there is an even more urgent need to provide a robust solution for restoring lost enamel, a problem that remains intractable for clinical dentistry. To address this problem, we propose research into an engineering methodology to spray the tooth with a thin mineral layer that is then densified and bonded to the underlying tooth using an ultrafast laser irradiation pulse. The cross-disciplinary LUMIN project will develop and exploit the technology of micro-nozzle bio-mineral delivery in Task (a) and its subsequent sintering using femto-second pulsed (fsp) lasers for the restoration of acid-eroded enamel. The operating wavelength of the proposed fsp lasers will be in the eye-safe regions of the near-IR (1500-2100 nm) and will offer flexibility in terms of energy/power delivery by engineering the laser cavity, which is the main goal of Task (b). An additional goal of Task (b), as stated in the objective section above, is to integrate the micro-nozzle bio-mineral delivery system from Task (a) with lasers on a single platform for achieving rapid sintering in the deposited bio-mineral layers on to the acid-eroded enamel surface. During this research, novel acid-resistant enamel mineral substitutes, in crystalline and gel forms, will be engineered and optimized for the micro-nozzle delivery in Task (a). The integration of the materials delivery system with the fsp-laser will then yield simultaneous sintering.. The engineering approaches herein will therefore yield 3 different platform technologies for future exploitation, which will be achieved with the support from the Integrated Knowledge Centre on Tissue Engineering and Medical Technologies at Leeds. We will investigate whether the use of a micro-nozzle for gel and suspension materials with an fsp-laser poses a risk of toxicity due to generation and release of nano-scale particulates (some may argue these might be photosensitized by the intense beam of the fsp-laser). In Task (c) we will therefore assess any nano-particle and photo-induced toxicity and perform a risk analysis. This will conform to standard clinical procedures with an aim to thus identify and minimise any imminent risk. Following Task (c), our goal in Task (d) is to implement the engineering approaches, developed in Tasks (a) and (b) together with the risk mitigation strategy in Task (c) for testing fsp-laser sintered enamel minerals in the oral environment using in-situ mouth appliance trials, a technique pioneered at the Leeds Dental Institute to minimising the risks in extensive in-vivo trials. In Task (d) the sintered materials will be characterised for acid erosion, durability, hardness, toughness, and flexural bend with using the assembled academic expertise in materials science and engineering and clinical dentistry.The IKC team will provide support, via Dr. Graeme Howling's expertise, to develop technology exploitation through the project partners, M-Squared Lasers, British Glass, and Giltec in the first instance. The project also aims to establish academic links with overseas academic institutions e.g. the IMI at Lehigh and Penn State in Materials Science, and with Stanford and Caltec in the US via the SUPA led EPSRC funded collaboration. The industry-academia link with the Photonics KTN in the UK is also expected to develop during the course of project.