The overall objective of this proposed research is to develop methods for the clinical assessment of lesion structure and activity. Improved imaging technologies employing non-ionizing radiation will significantly improve caries diagnosis and management. It is not sufficient to simply detect carious lesions, methods are needed to assess the activity of the lesion and determine if chemical intervention is needed. 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 quantified using optical imaging methods. There is a transparent highly mineralized outer surface zone presented on arrested lesions formed due to remineralization, which leads to decreased permeability to fluids including water and plaque generated acids. Previous studies have shown that the thickness of this surface zone can be measured nondestructively using polarization sensitive optical coherence tomography (PS-OCT), and have demonstrated that near-IR (NIR) reflectance and thermal imaging coupled with dehydration can be used to measure changes in the permeability of lesions in enamel and dentin. The overall objective of this proposal will be achieved through the following specific aims: (1) To test the hypothesis that the thickness of the highly mineralized transparent surface zone formed during remineralization correlates with the lesion permeability and activity; (2) To test the hypothesis that thermal and NIR reflectance dehydration methods can be used to measure the activity of secondary carious lesions around composite restorations; (3) To test the hypothesis that compact thermal and NIR reflectance probes for lesion activity assessment can be fabricated that are suitable for in vivo use. This project will allow us to determine the structural changes needed to arrest active lesions and provide methods for assessing the activity of lesions in a single examination to avoid unnecessary treatment and cavity preparations.

Public Health Relevance

Dental caries is one of the most prevalent chronic diseases affecting populations worldwide. Non-ionizing optical imaging technologies can be utilized for earlier detection and more accurate diagnosis of lesion severity and depth to avoid unnecessary surgical intervention and to allow safe routine monitoring of dental caries without radiation exposure. Furthermore, these technologies are suitable for the production of portable handheld instruments that can be used to detect and monitor decay without x-rays and to increase dental outreach globally.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Individual Predoctoral NRSA for M.D./Ph.D. Fellowships (ADAMHA) (F30)
Project #
5F30DE027264-04
Application #
9978807
Study Section
NIDR Special Grants Review Committee (DSR)
Program Officer
Frieden, Leslie A
Project Start
2017-09-01
Project End
2022-08-31
Budget Start
2020-09-01
Budget End
2021-08-31
Support Year
4
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of California San Francisco
Department
Dentistry
Type
Schools of Dentistry/Oral Hygn
DUNS #
094878337
City
San Francisco
State
CA
Country
United States
Zip Code
94118
Chang, Nai-Yuan N; Jew, Jamison M; Fried, Daniel (2018) Lesion Dehydration Rate Changes with the Surface Layer Thickness during Enamel Remineralization. Proc SPIE Int Soc Opt Eng 10473:
Chang, Nai-Yuan N; Jew, Jamison M; Simon, Jacob C et al. (2017) Influence of multi-wavelength laser irradiation of enamel and dentin surfaces at 0.355, 2.94, and 9.4??m on surface morphology, permeability, and acid resistance. Lasers Surg Med 49:913-927