LASER EFFECTS ON DENTAL HARD TISSUES

激光对牙齿硬组织的影响

• 批准号: 6818517
• 负责人: JOHN D FEATHERSTONE
• 金额: $ 36.74万
• 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/6818517
• 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）：使用特定激光治疗来防止釉质中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建立科学基础。在本提议中要测试的基本假设是，光到热的有效转换导致晶体组成和结构的变化，这增加了牙齿矿物（釉质和牙本质）对酸溶解的抵抗力。具体目标：（1）以正畸托槽周围牙釉质龋为模型系统，进行人类活体牙龋抑制的中试临床研究。(2)旨在检验为釉质和牙本质提供龋齿抑制的激光照射条件不会对组织的机械性能产生不良影响的假设。(3)为了检验以下假设：在通过IR激光照射的消融过程中，在牙釉质表面添加高度吸收的水层消除了磷酸钙的二次非磷灰石相，并允许激光照射显著降低牙釉质的酸溶解度。(4)为了检验以下假设，即先前显示的与釉质最有效相互作用以诱导对龋齿的抵抗的特定激光照射条件组可以被修改以抑制牙本质中的龋齿。拟议的研究将提供信息，将导致一个改进的方法来治疗窝沟龋，龋齿的形式是今天最普遍的。此外，牙本质和牙根龋的治疗可以通过使用激光来实现。此外，这些研究预计将导致识别激光照射条件，不仅可用于龋齿预防，而且可用于去除龋齿病变。经济、物理可管理、低能量激光器用于牙科诊所的龋齿预防和去除，在专门设计的波长、脉冲持续时间和能量密度条件下工作，是未来真实的和令人兴奋的可能性。