Jiangfeng Ding1, Weixiang Liu2, Alireza Sadr3, Yonghong He4, Arata Ebihara5, Yifan Li6. 1. Department of Stomatology, Shenzhen Nanshan People's Hospital and the Affiliated Shenzhen Sixth Hospital of Guangdong Medical University, Guangdong Province, China; Central Laboratory, Shenzhen Nanshan People's Hospital and the Affiliated Shenzhen Sixth Hospital of Guangdong Medical University, Guangdong Province, China. 2. School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen, Guangdong, China. 3. Department of Restorative Dentistry, University of Washington School of Dentistry, Seattle, Washington. 4. Institute of Optical Imaging and Sensing, Shenzhen Key Laboratory for Minimal Invasive Medical Technologies, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China. 5. Division of Oral Health Sciences, Medical and Dental Sciences Track, Department of Pulp Biology and Endodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan. Electronic address: a.ebihara.endo@tmd.ac.jp. 6. Central Laboratory, Shenzhen Nanshan People's Hospital and the Affiliated Shenzhen Sixth Hospital of Guangdong Medical University, Guangdong Province, China. Electronic address: liyifan2005@yahoo.com.
Abstract
INTRODUCTION: The accurate detection of periradicular lesions located under a nonperforated cortical plate poses a challenge in endodontic microsurgery. Optical coherence tomography (OCT) is a noninvasive imaging method that has been successfully used in many dental applications. In this study, we investigated if spectral-domain OCT (SD-OCT) could be used to determine simulated periradicular lesions. METHODS: Twenty-eight cavities with different depths were prepared on bone plates obtained from 5 porcine mandibles. Both 3-dimensional SD-OCT imaging and micro-computed tomographic (micro-CT) imaging were used to image the bottom of the air-filled cavity and the cavity filled with soft tissue for comparison. The residual bone thickness under the cavity was measured by SD-OCT and micro-CT imaging and compared using the Pearson correlation. RESULTS: The air-filled lesions were readily detected; yet, filling of the cavity with soft tissue diminished the appearance of the lesion boundaries in the SD-OCT images. The optical values of residual bone thickness obtained from SD-OCT ranged from 0.14-2.11 mm, which corresponded to the range of 0.26-1.18 mm from micro-CT imaging. A strong correlation was found between the 2 imaging modalities (r = 0.96; range, 0.94-0.98). The slope (1.56) of the linear regression matched the bulk refractive index of bone tissues. CONCLUSIONS: SD-OCT allows for visualization of the lesion boundaries via intact bone surfaces and may be a promising, practical, and nonirradiating adjunct tool for chairside localization of periradicular lesions in bone.
INTRODUCTION: The accurate detection of periradicular lesions located under a nonperforated cortical plate poses a challenge in endodontic microsurgery. Optical coherence tomography (OCT) is a noninvasive imaging method that has been successfully used in many dental applications. In this study, we investigated if spectral-domain OCT (SD-OCT) could be used to determine simulated periradicular lesions. METHODS: Twenty-eight cavities with different depths were prepared on bone plates obtained from 5 porcine mandibles. Both 3-dimensional SD-OCT imaging and micro-computed tomographic (micro-CT) imaging were used to image the bottom of the air-filled cavity and the cavity filled with soft tissue for comparison. The residual bone thickness under the cavity was measured by SD-OCT and micro-CT imaging and compared using the Pearson correlation. RESULTS: The air-filled lesions were readily detected; yet, filling of the cavity with soft tissue diminished the appearance of the lesion boundaries in the SD-OCT images. The optical values of residual bone thickness obtained from SD-OCT ranged from 0.14-2.11 mm, which corresponded to the range of 0.26-1.18 mm from micro-CT imaging. A strong correlation was found between the 2 imaging modalities (r = 0.96; range, 0.94-0.98). The slope (1.56) of the linear regression matched the bulk refractive index of bone tissues. CONCLUSIONS:SD-OCT allows for visualization of the lesion boundaries via intact bone surfaces and may be a promising, practical, and nonirradiating adjunct tool for chairside localization of periradicular lesions in bone.