Clinical performance of a laser ¯uorescence device for detection of occlusal caries lesions Lussi A, Megert B, Longbottom C, Reich E, Francescut P. Clinical performance of a laser ¯uorescence device for detection of occlusal caries lesions. Eur J Oral Sci 2001; 109: 14±19. # Eur J Oral Sci, 2001 Children and adolescents must be examined often for occlusal caries. Diagnosis of ®ssure caries is dif®cult especially when the tooth surface appears seemingly intact. It has been shown that using traditional clinical methods, as little as 20% of teeth with ®ssure caries under intact surfaces were correctly recognised as such. Therefore, new methods for increasing the accuracy of diagnosis have been sought for years. Recently, a new device, based on ¯uorescence measurements, was introduced. The purpose of this study was to test the device under in vivo conditions in order to provide recommendations for its use in the dental of®ce. Seven general dental practitioners examined a total of 332 occlusal surfaces in 240 patients. Caries extent was determined for each site after operative interven- tion ( =`gold standard'). Clinical inspection and analysis of bitewing radio- graphs exhibited statistically signi®cant lower sensitivities (31±63%) than did the DIAGNOdent device (sensitivity §92%). It is recommended that the laser device is used in the decision-making process in relation to the diagnosis of occlusal caries as a second opinion in cases of doubt after visual inspection. A. Lussi 1 , B. Megert 1 , C. Longbottom 2 , E. Reich 3 , P. Francescut 1 1 Department of Operative, Preventive and Paediatric Dentistry, School of Dental Medicine University of Bern, Switzerland, 2 Dental Health Services Research Unit and Dental School, University of Dundee, UK, 3 Department of Periodontology and Conservative Dentistry, University of Saarland, Homburg, Germany A. Lussi, Klinik fu È r Zahnerhaltung, Freiburgstrasse 7, CH-3010 Bern, Switzerland Telefax: +41±31±6329875 E-mail: adrian.lussi@zmk.unibe.ch Key words: caries detection; caries diagnosis; radiography; DIAGNOdent; occlusal caries; laser ¯uorescence Accepted for publication November 2000 Today's commonly used diagnostic methods for ®ssure caries detection exhibit high speci®city but low sensitiv- ity. In most studies, the speci®city, that is the correct recognition of sound teeth, appears to be greater than 80% for all traditional methods (1±10). This means that only a few sound teeth (i.e. without dentinal ®ssure caries) are diagnosed wrongly as having dentinal caries and are therefore erroneously treated by operative intervention. In view of today's relatively low caries incidence, this particular characteristic of a test method is important: teeth which can be kept unrestored for many years with adequate prevention should not be treated with restorations (11). The sensitivity of conventional diagnostic methods, i.e. the ability to correctly recognise decayed teeth (i.e. with dentinal caries), has been shown to be between 62% and 90% for teeth with visible cavities in ®ssures (12). No statistical differences were found between the various diagnostic methods. The correct clinical diagnosis of teeth with dentinal caries under macroscopically intact surfaces (often called hidden caries), however, has been shown to be signi®cantly lower, with reported sensitivities as low as 12% (1, 2, 4, 6, 10). The ®rst two investigations also found that additional probing with an explorer did not improve the diagnostic performance. Regular prob- ing with commonly applied force may, in fact, disturb areas of demineralised enamel to the point of disrupting the surface, which, in turn, may lead to more rapid progression of the carious process (13±16). Sensitivity of visual inspection can be improved when bitewing radio- graphs are used (2, 4, 6, 8, 10, 12). In this context, it is important to note that radiographs will aid the detection of occlusal caries only if the disease has already pro- gressed into dentine. A carious lesion visible on a radio- graph is signi®cantly more infected with lactobacilli and Streptococcus mutans than a non-X-ray-detectable lesion. If bacterial infection should prompt operative interven- tion, radiographic appearance on bitewing radiographs is an important aid to treatment planning (17). Recently, a new diagnostic method and device for intact (occlusal) surfaces was presented. It is based on ¯uorescence measurements and produced promising results in vitro (18, 19). High sensitivity was observed for teeth with hidden caries, and the reproducibility of the results was such that monitoring of the course of the carious process may be possible for occlusal lesions. The aim of this study was to test the method and device under ®eld conditions in the dental of®ce and compare the results with those of clinical inspection and of analysis of bitewing radiographs in order to provide recom- mendations in relation to the clinical utility, as well as the limitations of the method. Material and methods The investigation was carried out by seven practising dentists in Switzerland and Germany. It comprised 240 patients of a mean age of 19.8t8.4 yr. A total of 332 Eur J Oral Sci 2001; 109: 14±19 Printed in UK. All rights reserved Copyright # Eur J Oral Sci 2001 European Journal of Oral Sciences ISSN 0909-8836