 Original Contribution DIAGNOSTIC PERFORMANCE OF ICDAS II, FLUORECAM AND ULTRASOUND FOR FLAT SURFACE CARIES WITH DIFFERENT DEPTHS TAGGEDPFUNDA YANIKOGLU,* HILAL AVCI, y ZEYNEP CEREN CELIK, y and DILEK TAGTEKIN y TAGGEDEND * Department of Restorative Dentistry, Faculty of Dentistry, Kent University, Istanbul, Turkey; and y Department of Restorative Dentistry, Faculty of Dentistry, Marmara University, Istanbul, Turkey (Received 30 October 2018; revised 5 March 2020; in final from 10 March 2020) ABSTRACT—The use of ultrasound for the diagnosis of natural caries lesions with different depths on flat surfa- ces of permanent molar teeth was studied. A total of 200 freshly extracted permanent molar teeth with natural caries lesions were included. After evaluation with International Caries and Detection Assessment System II (ICDAS II), mineral loss and lesions in the teeth were detected with a fluorescence device, FluoreCam and lesion depths were measured using ultrasound. The teeth were sectioned and examined histologically using a micro- scope. The intraclass correlation coefficient was 0.97 for the ultrasound system, 0.65 for the ICDAS II classifica- tion and 0.59 for FluoreCam (p < 0.001 for all). With an increase in ICDAS II scores, mean ultrasound values, FluoreCamSize and microscope measurements increased numerically, while FluoreCamIntensity and Fluore- CamImpact measurements inversely decreased (p < 0.001). There was a high level of agreement between histo- logic diagnosis and ultrasound. Ultrasound and FluoreCam can be used to detect enamel caries on flat surfaces. (E-mail: dt.zcerencelik@gmail.com) © 2020 World Federation for Ultrasound in Medicine & Biology. All rights reserved. Keywords: Caries detection, Ultrasound, Fluorescence, International Caries, Detection Assessment System. INTRODUCTION Dental caries is a disease of the dental hard tissue caused by decalcification of the inorganic parts of the tooth. It is caused by disruption of the physiologic balance between the oral microbial biofilm layer and the minerals in the tooth structure. Early diagnosis of caries is essential for preventing any tooth tissue loss and planning appropriate non-invasive treatment. Practitioners utilize several tools to diagnose caries, such as X-rays, visible light, laser, electron flow and ultrasound (Mital et al. 2014). In daily practice, the diagnosis of caries is based mainly on clini- cal observation using dental mirrors, sound and radiogra- phy. However, the use of sharp sounds and ionizing radiation is invasive (Ekstrand et al. 1998). The ideal diagnostic method must be reliable and sensitive enough to distinguish initial lesions, be able to identify lesion activity and be easily understandable, feasible and repeatable by clinicians and researchers, as well as non- invasive, painless and harmless (Pitts 1997, 2004). This study’s hypothesis was that ultrasound, a non- invasive, painless and repeatable method, may detect pre- cavitated lesions precisely and quantitatively. Therefore, the aim of this study was to diagnose natural caries lesions of different depths using ultrasound and compare the results with those for International Caries and Detection Assessment System II (ICDAS II), a fluorescence device (FluoreCam) and a light microscope as the gold standard method. ICDAS II ICDAS II was first introduced as a clinical scoring system for the identification and evaluation of caries in accordance with the stage and determination of lesion changes over time. It can be easily monitored and stan- dardized for in vitro and in vivo studies (Pitts 1997; Ismail et al. 2007; Selwitz et al. 2007). The ICDAS II criteria were developed for the evaluation of all phases of caries development from the initial stages of deminer- alization to the cavitation stage (Pitts 2004). FluoreCam Dental hard tissue has its own natural fluorescence called autofluorescence. The fluorescence property of the Address correspondence to: Zeynep Ceren Celik, Marmara Uni- versity Faculty of Dentistry, Department of Restorative Dentistry, Basibuyuk 9/3 Maltepe- Istanbul, Turkey. E-mail: dt.zcerencelik@gmail.com 1 ARTICLE IN PRESS Ultrasound in Med. & Biol., Vol. 00, No. 00, 11754, 2020 Copyright © 2020 World Federation for Ultrasound in Medicine & Biology. All rights reserved. Printed in the USA. All rights reserved. 0301-5629/$ - see front matter https://doi.org/10.1016/j.ultrasmedbio.2020.03.007