[2] [2] Maeng Youjin, Lee Hyungsuk, Lee Eunsong, et al. Noninvasive detection of microleakage in all-ceramic crowns using quantitative light-induced fluorescence technology[J]. Photodiagnosis and Photodynamic Therapy, 2020, 30: 101672.

[3] [3] Brouwer F, Askar H, Paris S, et al. Detecting secondary caries lesions: a systematic review and meta-analysis[J]. J. Dent Res., 2016, 95(2): 143-151.

[4] [4] FAN Shuting, HE Yuezhi, Benjamin S Ung, et al. The growth of biomedical terahertz research[J]. Journal of Physics D: Applied Physics, 2014, 47(37): 374009.

[7] [7] Daniela S Lopes, Wellington S Souza, Renato E de Araujo, et al. Terahertz time-domain spectroscopy of healthy and carious dental tissues[C]//The European Conference on Lasers and Electro-Optics, 2019: 1-1(DOI: 10.1109/CLEOE-EQEC.2019.8871841).

[8] [8] Karagoz B, Kamburoglu K, Altan H. Terahertz pulsed imaging for the monitoring of dental caries: a comparison with X-ray imaging[C]//Proceedings of SPIE, 2017, 10417P( https://doi.org/ 10.1117/ 12.2285991).

[9] [9] Kamburo?lu K?van?, Karag?z Burcu, Altan Hakan, et al. An ex vivo comparative study of occlusal and proximal caries using terahertz and X-ray imaging[J]. Dento Maxillo Facial Radiology, 2019, 48(2): 20180250.

[10] [10] Hampton P, Agathoklis P, Bradley C. A new wave-front reconstruction method for adaptive optics system using wavelets[J]. IEEE Journal of Selected Topics in Signal Processing, 2008, 2(5): 781-792.

[11] [11] Sevcenco I S, Hampton P J, Agathoklis P. Seamless stitching of images based on a Haar wavelet 2D integration method[C]//17th International Conference on Digital Signal Processing (DSP), 2011: 1-6(DOI: 10.1109/ ICDSP.2011.6004934).

[12] [12] Ioana S Sevcenco, Peter J Hampton, Panajotis Agathoklis. A wavelet based method for image reconstruction from gradient data with applications[J]. Multidimensional Systems and Signal Processing, 2015, 26(3): 717-737.

[13] [13] YAN Qing, XU Yi, YANG Xiaokang, et al. Single image super resolution based on gradient profile sharpness[J]. IEEE Transactions on Image Processing, 2015, 24(10): 3187 - 3202.