LASER EFFECTS ON DENTAL HARD TISSUES

激光对牙齿硬组织的影响

• 批准号: 6927843
• 负责人: JOHN D FEATHERSTONE
• 金额: $ 33.06万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6927843
• 关键词: X ray crystallography; adolescence (12-20); animal tissue; atomic force microscopy; clinical research; clinical trials; computer simulation; dental caries; dental caries inhibitor; dental pulp; dentin; hardness; human subject; human therapy evaluation; laser therapy; longitudinal human study; preventive dentistry; radiation therapy dosage; radiobiology; restorative dentistry; scanning electron microscopy; therapy design /development; thermostability; tooth enamel; tooth root

DESCRIPTION (provided by applicant): The concept of using specific laser treatment to prevent the progression of dental caries in enamel is close to becoming an exciting clinical reality. The overall objective of the studies is to develop an in-depth understanding of the interactions of laser light with dental hard tissues (enamel and dentin) and to establish a scientific basis for the safe and effective use of lasers on these tissues. The underlying hypothesis to be tested in the present proposal is that efficient conversion of light to heat results in changes in crystal composition and structure which increase the resistance of dental mineral (enamel and dentin) to dissolution by acid. Specific Aims: (1) To conduct a pilot scale clinical study of caries inhibition in living teeth in humans using caries in enamel around orthodontic brackets as a model system. (2) To test the hypothesis that laser irradiation conditions that provide caries inhibition for enamel and dentin will not have undesirable effects on the mechanical properties of the tissues. (3) To test the hypothesis that the addition of a highly absorbing layer of water to the surface of dental enamel during ablation by IR laser irradiation eliminates secondary non-apatite phases of calcium phosphate and allows the laser irradiation to markedly reduce the acid solubility of the enamel. (4) To test the hypothesis that the specific sets of laser irradiation conditions previously shown to most effectively interact with enamel to induce resistance to dental caries can be modified for caries inhibition in dentin. The proposed studies will provide information that will lead to an improved method for treating pit and fissure caries, the caries form that is most prevalent today. Further, the treatment of dentinal and root caries may be possible by the use of lasers. Additionally, the studies are expected to lead to the identification of laser irradiation conditions that can be used not only for caries prevention, but also for removal of carious lesions. The development of economical, physically manageable, low energy lasers for caries prevention and removal in the dental office, that operate at specifically designed wavelength, pulse duration, and fluence conditions, is a real and exciting possibility for the future.

描述(由申请人提供)：使用特定的激光治疗来防止牙釉质中的龋齿进展的概念即将成为令人兴奋的临床现实。研究的总体目标是深入了解激光与牙齿硬组织(牙釉质和牙本质)的相互作用，并为在这些组织上安全有效地使用激光奠定科学基础。本提案要检验的基本假设是，光到热的有效转换会导致晶体成分和结构的变化，从而增加牙科矿物(牙釉质和牙本质)对酸溶解的抵抗力。具体目的：(1)以正畸托槽周围牙釉质中的龋病为模型系统，开展活体牙齿抑龋性的中试临床研究。(2)验证激光照射条件对牙釉质和牙本质的抑龋性不会对组织的力学性能产生不良影响的假设。(3)通过在牙釉质表面加一层高吸水层，消除了磷酸钙的次生非磷灰石相，从而显著降低了牙釉质的酸溶度，从而验证了红外激光消融牙釉质的假设。(4)验证这样一种假设，即以前被证明最有效地与牙釉质相互作用以诱导抗龋性的特定激光照射条件组可以被修改以抑制牙本质中的龋病。拟议中的研究将提供信息，从而改进治疗窝沟龋齿的方法，窝沟龋齿是当今最普遍的一种龋齿形式。此外，使用激光治疗牙本质和根面龋齿是可能的。此外，这些研究有望确定激光照射条件，这些条件不仅可以用于预防龋齿，还可以用于去除龋损。在牙科诊所开发经济的、物理上可管理的、低能量的激光用于预防和去除龋齿，它在特定设计的波长、脉冲持续时间和通量条件下运行，在未来是一个真实而令人兴奋的可能性。