Optical Assessment of Caries Lesion Structure and Activity

描述(申请人提供)：这项拟议研究的总体目标是开发用于检测和诊断早期龋齿(龋齿)的近红外(NIR)成像方法。在发育的早期阶段，需要新的、更复杂的诊断工具来检测和描述龋损。如果在空化前足够早地发现龋损，则可以通过氟化物治疗、抗菌治疗、改变饮食或低强度激光照射等非手术方法阻止/再矿化。仅仅检测龋损是不够的，需要用各种方法来评估龋损的活动性，并确定是否需要化学干预。以往的体外和体内研究表明，光学相干层析成像可以无损地成像亚表面病变结构，并测量高度矿化的表面层的厚度。其他研究表明，脱水率可以与病变活动性相关，并且可以用光学方法测量。支持这一建议的中心假设是，由于龋病、停滞性病变和发育缺陷引起的活动性病变之间存在结构上的差异，这些差异可以使用近红外波长的光学成像方法来非破坏性地解决。由于釉质的质地和颜色相似，釉质的停滞性病变和发育缺陷很容易被误认为是活动性的早期龋损。停滞性病变和轻度发育缺陷通常具有坚硬的外层或表层，其矿物质含量高于病变的身体，这降低了病变的通透性。这项建议的总体目标将通过以下具体目标实现：(1)检验可用光学方法评估牙齿冠面和牙根表面病变活动性的假设，(2)检验可用近红外成像方法区分牙齿冠面龋损和因发育缺陷引起的釉质矿化不足的假说。如果这些研究和未来的临床试验取得成功，这种新的成像技术将被用于检测和监测早期龋损，而不使用电离辐射，从而实现保守的非手术干预和保存健康的组织结构。

DESCRIPTION (provided by applicant): The overall objective of this proposed research is to develop near-infrared (NIR) imaging methods for the detection and diagnosis of early dental caries (dental decay). New, more sophisticated diagnostic tools are needed for the detection and characterization of caries lesions in the early stages of development. If carious lesions are detected early enough, before cavitation, then they can be arrested/remineralized by non-surgical means through fluoride therapy, anti-bacterial therapy, dietary changes, or by low intensity laser irradiation. It is not sufficient to simply detect caries lesions, methods are needd to assess the activity of the lesion and determine if chemical intervention is needed. Previous in vitro and in vivo studies have demonstrated that optical coherence tomography can be used to nondestructively image the subsurface lesion structure and measure the thickness of the highly mineralized surface zone. Other studies have demonstrated that the rate of dehydration can be correlated with the lesion activity and that rate can be measured using optical methods. The central hypothesis underlying this proposal is that there are structural differences between active lesions due to caries, arrested lesions and developmental defects, and these differences can be resolved nondestructively using optical imaging methods at NIR wavelengths. Arrested lesions and developmental defects of enamel can be easily mistaken for active early caries lesions due to similar texture and color. Arrested lesions and mild developmental defects typically have a hard outer layer or surface zone of higher mineral content than the body of the lesion which reduces the lesion permeability. The overall objectives of this proposal will be achieved through the following specific aims: (1) To test the hypothesis that optical methods can be used to assess lesion activity on tooth coronal and root surfaces, (2) To test the hypothesis that NIR imaging methods can be used to differentiate caries lesions on tooth coronal surfaces from enamel hypomineralization due to developmental defects. It is likely that if these studies and future clinical trials are a success, this novel imaging technology will be employed for the detection and monitoring of early carious lesions without the use of ionizing radiation, thereby enabling conservative non-surgical intervention and the preservation of healthy tissue structure.