11 European Archives of Paediatric Dentistry // 10 (Suppl. 1). 2009 Key words: caries detection, laser fluorescence, primary molars Postal address: Dr. K. Kavvadia, Dept of Paediatric Dentistry, Dental School, University of Athens, 2 Thivon St., Goudi, 115 27 Athens, Greece. Email: kavad@dent.uoa.gr D. Apostolopoulou, P. Lagouvardos, K. Kavvadia, L. Papagiannoulis. Dept. Paediatric Dentistry, School of Dentistry, University of Athens, Greece Histological validation of a laser fluorescence device for occlusal caries detection in primary molars Abstract AIM: This was to validate in vitro a laser fluorescence de- vice, DIAGNOdent TM 2095 – DD, on the detection of occlusal caries in primary molars using the histological examination as the gold standard and to compare the laser fluorescence findings to the results of the conventionally used diagnostic methods. STUDY DESIGN AND METHODS: 111 occlusal pits in 24 extracted primary molars were examined for caries by one trained operator (Intra-examiner Reliability K>0.83), using direct visual (DV), indirect visual (IDV), radiographic (XR) and fluorescence (DD) examinations and then the extent of caries was determined histologically. Sensitivity, specifi- city, accuracy and the area under the ROC curve – AUC were calculated for all methods, using the histological evaluation as the gold standard. STATISTICS: Differences between examination methods were estimated by pair-wise compari- son of their respective AUC. RESULTS: DD’s sensitivity for enamel and for dentine lesions respectively was 0.90 and 0.36, its specificity 0.36 and 0.91 and its accuracy 0.61 and 0.65. The DD device exhibited better sensitivity than specifi- city for enamel lesions and better specificity than sensitivity for lesions into dentine. The DD device was found to have the highest sensitivity for lesions into enamel, specificity and accuracy and as well as the largest AUC compared with all other methods. For lesions into dentine however, according to AUC values the DD was not statistically significant dif- ferent from the other methods. CONCLUSION: Compared with the other methods, the DD had the highest validity for enamel caries while its validity for caries into dentine was not statistical different from the other methods. Introduction Laser fluorescence was first used for the detection of early carious lesions in the 1980’s, as a non-invasive and non- harmful method [Bjelkhagen et al., 1982]. In order to make such a method applicable for the every day clinical use, a portable device DIAGNOdent TM 2095 (KaVo 1998, Bibber- ach, Germany) has been introduced, in which fluorescence alterations of carious dental tissues are expressed as read- ings on a scale from 0 to 99 [KaVo, 2002]. This device has been used in the detection of occlusal caries in permanent teeth both in vitro and in vivo. The results of many clinical and experimental studies in the permanent dentition have shown that laser fluorescence caries detection when com- pared with visual examination was more sensitive but less specific for the detection of dentine caries and less sensi- tive but more specific for enamel caries [Bader and Shugars, 2004; Lussi et al., 2004; Burin et al., 2005; Olmez et al., 2006; Reis et al., 2006]. Several studies have been published for primary teeth test- ing the validity of the DIAGNOdent TM device (DD) by compar- ing it with conventional diagnostic methods, however results have varied [Attrill and Ashley, 2001; Antonnen et al., 2003; Lussi and Francescut, 2003; Rocha et al., 2003; Bengtson et al., 2005; Mendes et al., 2006; Costa et al., 2007; Braga et al., 2008; Kavvadia and Lagouvardos, 2008; Rodrigues et al., 2008]. In the in vivo studies validation was based on histological examination of retrieved teeth after exfoliation [Rocha et al., 2003], on direct visual examination [Antonnen et al., 2003] or on pit and fissure opening [Costa et al., 2007; Kavvadia and Lagouvardos, 2008]. These studies found DD to have sensitivity from 0.43 to 0.60 for enamel caries and 0.73 to 0.77 for caries into dentine while specificity ranged from 0.88 to 0.90 for enamel caries and from 0.62 to 0.95 for caries into dentine. The cut-off limits used in these studies for caries into dentine ranged from 21 to 31. In the in vitro studies for the primary dentition, the DD was validated by using the histological examination as the gold standard [At- trill and Ashley, 2001; Lussi and Francescut, 2003; Mendes et al., 2006; Braga et al., 2008; Rodrigues et al., 2008]. These studies found sensitivity of DD from 0.24 to 0.75 for enamel caries and from 0.20 to 0.82 for caries into dentine while specificity ranged from 0.68 to 0.93 for enamel caries and 0.85 to 0.93 for caries into dentine. The cut-off limits used for dentine involvement, 11 to 17, were lower than those re- ported in vivo. When the DD was compared with direct visual examination for caries into dentine, it was found to have higher sensi- tivity but lower specificity [Attrill and Ashley, 2001; Mendes et al., 2006; Braga et al., 2008] while for enamel caries, it was less sensitive but more specific [Rodrigues et al., 2008]. In another study, however, its diagnostic performance was found to be better than visual examination both for enamel and dentine caries [Lussi and Francescut, 2003]. A wide variation exists among studies regarding the sen- sitivity and specificity of DD for enamel and dentine caries detection and the relevant cut off limits used. Accordingly,