Early Caries Detection with Near-IR Light

描述（由申请人提供）：拟议研究的总体目标是开发用于早期龋齿（蛀牙）检测和诊断的非侵入性光学设备。需要新的、更复杂的诊断工具来检测和表征早期发展阶段的龋齿病变。如果及早发现龋齿，可以通过氟治疗、抗菌治疗、饮食改变或低强度激光照射等非手术手段阻止或逆转龋齿。在400-700纳米可见光范围内，限制通过牙釉质进行光学成像的主要因素是光散射。在可见光范围内，光在健全的牙釉质和牙本质中的散射足够强，从而掩盖了通过牙齿的光传输。光在牙釉质中的散射强度随波长的增加而明显减小。因此，我们假设在1310纳米的近红外区域，由于声音牙齿硬组织的弱散射和吸收，为新的光学成像模式提供了最大的潜力。在较长的波长下，组织中对水的吸收显著增加，减少了红外光的穿透。本应用的总体目标将通过以下具体目的来实现：1)验证近红外偏振敏感光学相干断层扫描（PS-OCT）可以用于准确评估体内自然咬合病变的深度和严重程度的假设。2)验证1310-nm近红外（NIR）成像系统在体内获得近端间和咬合龋齿病变高对比度图像的假设。如果这些研究和未来的临床试验取得成功，这些牙齿硬组织成像的新技术很可能被用于检测和监测早期龋齿病变，而不使用电离辐射，从而使保守的非手术干预和健康组织结构的保存成为可能。此外，这种提出的成像技术很可能使临床医生能够检测和量化由于周围良好组织结构而无法用常规x线摄影解决的咬合病变的严重程度。

DESCRIPTION (provided by applicant): The overall objective of the proposed research is to develop non-invasive optical devices 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, they can be arrested/reversed by non-surgical means through fluoride therapy, anti- bacterial therapy, dietary changes, or by low intensity laser irradiation. The principal factor limiting optical imaging through the enamel of the tooth in the visible range of 400-700-nm is light scattering. Light scattering in sound enamel and dentin is sufficiently strong in the visible range to obscure light transmission through the tooth. The magnitude of light scattering in Dental enamel decreases markedly with increasing wavelength. Therefore, we posit that the near-IR region at 1310-nm offers the greatest potential for new optical imaging modalities due to the weak scattering and absorption in sound Dental hard tissue. At longer wavelengths, absorption of water in the tissue increases markedly reducing the penetration of IR light. The overall objective of this application will be achieved through the following Specific Aims: 1) to test the hypothesis that near-IR polarization-sensitive optical coherence tomography (PS-OCT) can be used for the accurate assessment of the depth and severity of natural occlusal lesions in vivo. 2) To test the hypothesis that a near-IR (NIR) imaging system operating at 1310-nm can be used to acquire high-contrast images of interproximal and occlusal caries lesions in vivo. It is likely that if these studies and future clinical trials are a success, that these novel technologies for imaging Dental hard tissue 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. Moreover, it is probable that this proposed imaging technology would enable the clinician to detect and quantify the severity of occlusal lesions that are not resolvable with conventional radiography due to the surrounding sound tissue structure.