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Background and Objective A safer alternative method to radiographic imaging is needed. We present a multispectral near‐infrared scanning fiber endoscope (nirSFE) for dental imaging which is designed to be the smallest imaging probe with near‐infrared (NIR) imaging (1200–2000 nm). Materials and Methods The prototype nirSFE is designed for wide‐field forward viewing of scanned laser illumination at 1310, 1460, or 1550 nm. Artificial lesions with varying sizes and locations were prepared on proximal surfaces of extracted human teeth to examine capability and limitation of this new dental imaging modality. Nineteen artificial interproximal lesions and several natural occlusal lesions on extracted teeth were imaged with nirSFE, OCT, and microCT. Results Our nirSFE system has a flexible shaft as well as a probe tip with diameter of 1.6 mm and a rigid length of 9 mm. The small form factor and multispectral NIR imaging capability enables multiple viewing angles and reliable detection of lesions that can extend into the dentin. Among nineteen artificial interproximal lesions, the nirSFE reflectance imaging operating at 1460‐nm and OCT operating at 1310‐nm scanned illumination exhibited high sensitivity for interproximal lesions that were closer to occlusal surface. Diagnosis from a non‐blinded trained user by looking at real‐time occlusal‐side nirSFE videos indicate true positive rate of 78.9%. There were no false positives. Conclusions This study demonstrates that nirSFE may be used for detecting occlusal lesions and interproximal lesions located less than 4 mm under the occlusal surface. Major advantages of this imaging system include multiple viewing angles due to flexibility and small form factor, as well as the ability to capture real‐time video. The multispectral nirSFE has the potential to be employed as a low‐cost dental camera for detecting dental lesions without exposure to ionizing radiation.
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Near-Infrared Imaging of Artificial Enamel Caries Lesions with a Scanning Fiber Endoscope
Several studies have shown that near-infrared imaging has great potential for the detection of dental caries lesions. A miniature scanning fiber endoscope (SFE) operating at near-infrared (NIR) wavelengths was developed and used in this study to test whether the device could be used to discriminate demineralized enamel from sound enamel. Varying depths of artificial enamel caries lesions were prepared on 20 bovine blocks with smooth enamel surfaces. Samples were imaged with a SFE operating in the reflectance mode at 1310-nm and 1460-nm in both wet and dry conditions. The measurements acquired by the SFE operating at 1460-nm show significant difference between the sound and the demineralized enamel. There was a moderate positive correlation between the SFE measurements and micro-CT measurements, and the NIR SFE was able to detect the presence of demineralization with high sensitivity (0.96) and specificity (0.85). This study demonstrates that the NIR SFE can be used to detect early demineralization from sound enamel. In addition, the NIR SFE can differentiate varying severities of demineralization. With its very small form factor and maneuverability, the NIR SFE should allow clinicians to easily image teeth from multiple viewing angles in real-time.
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- Award ID(s):
- 1631146
- PAR ID:
- 10088936
- Date Published:
- Journal Name:
- Sensors
- Volume:
- 19
- Issue:
- 6
- ISSN:
- 1424-8220
- Page Range / eLocation ID:
- 1419
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/s19061419
