Validity of Soprolife camera and Calcivis device in caries lesion activity assessment Noémie Drancourt, 1 Valérie Roger-Leroi, 2 Bruno Pereira, 3 Marie-Laure Munoz-Sanchez, 1 Natacha Linas, 1 Françoise Vendittelli 4 and Sophie Doméjean* 1 Introduction A recent systematic review on the topic of activity assessment of coronal carious lesions (AACCL) in clinical settings reported that four groups of techniques are currently available: 1) systems based on combinations of visual and tactile criteria; and devices based on 2) pH assessment; 3) fluorescence; or 4) bioluminescence. 1,2 The authors concluded that, despite some limitations, the most robust validation studies were related to the systems based on combinations of visual and tactile parameters. 3,4,5 Despite the lack of data regarding the use of those systems in everyday clinical practice, it is postulated that they are rarely used in the context of a busy dental practice; indeed, several parameters and scoring systems might be too complicated to be implemented into a routine for many. Manufacturers and researchers are thus working together on the development of further tools to simplify the AACCL at the dental chair. Te pH assessment was one of the frst methods trialled but is no longer in the professional market. 4 Nowadays, fuorescence and bioluminescence are the two technologies under investigation. Tree fuorescence-based devices have been subject to AACCL validation studies – namely the Soprolife camera, the DIAGNOdent and the Quantitative Light Fluorescence (QLF) – and only one based on bioluminescence: Calcivis. 1 Soprolife is a device that was introduced in 2009 which combines a high-magnifcation intraoral camera and fuorescence technology, aiming to analyse differences in density, structure and/or chemical composition of biological tissue. 6,7 Its indications are, according to the manufacturer, the detection (presence/absence) and the activity assessment (active/inactive) of carious lesions. If several studies have been undertaken to assess its validity in terms of detection, 6,8 data towards activity assessment are lacking. Calcivis Caries Activity Imaging System is an innovative approach for lesion activity assessment (LAA); it is based on the bioluminescence of a photosensitive protein, which is specifc for free calcium ions present at the surface of active carious lesions. 9 Validity of Calcivis in terms of sensitivity (SE), specifcity (SP), area under the receiver-operating curve Caries activity assessment is one of the components of caries diagnosis at the lesion level; it allows better defnition of the appropriate management option lesion by lesion. Manufacturers and researchers are working together on the development of tools/devices to simplify the activity assessment of coronal carious lesions at the dental chair; the latest are based on fuorescence (for example, Soprolife) and bioluminescence (Calcivis). Validation studies are needed to confrm the interest of the newly developed tools/devices. Key points Abstract Aim An ex vivo study was performed to assess (gold standard [GS]: Nyvad criteria) sensitivities (SEs) and specifcities (SPs) of Soprolife (fuorescence) and Calcivis (bioluminescence) – indicated, by the manufacturers, for activity assessment of coronal carious lesions (AACCL). We also calculated the positive and negative predictive values, positive and negative log-likelihoods, inter-examiner and intra-examiner variations, and concordance rates (CRs) of both devices compared to GS and to each other. Materials and methods One hundred and twenty-one extracted posterior teeth were included. Within 48 hours after extraction, ICDAS and Nyvad scores were determined and occlusal photographs (Soprolife and Calcivis captures) were taken. Three examiners were asked to score, independently, twice (T0; T0 + 15 days), the caries activity status (active/ inactive) for each image. Results Both devices showed modest SEs and SPs. The only statistically signifcant diferences between devices were for SE (p = 0.04) in favour of Soprolife (all ICDAS scores combined) and for SP (p = 0.03) in favour of Calcivis (ICDAS 3, 4). There were higher CRs for Soprolife than for Calcivis (compared to GS). Intra- and inter-examiner variations were 76–86.8% and 71.9–85.1% for Soprolife, and 79.3–89.3% and 72.7–86.8% for Calcivis, respectively. Conclusion In light of the results, it seems difcult to confrm the validation of Soprolife and Calcivis for AACCL. 1 Department of Operative Dentistry and Endodontics, Université Clermont Auvergne, UFR d’Odontologie, CROC EA 4847, 2 rue de Braga, 63100 Clermont-Ferrand, France; 2 Department of Oral Biology, Université Clermont Auvergne, UFR d’Odontologie, CROC EA 4847, 2 rue de Braga, 63100 Clermont-Ferrand, France; 3 Direction de la Recherche Clinique et des Innovations, CHU Gabriel Montpied, Rue Montalembert, 63000 Clermont-Ferrand, France; 4 Department of Obstetrics, CHU Estaing, 1 rue Lucie et Raymond Aubrac, 63003 Clermont-Ferrand, France. *Correspondence to: Sophie Doméjean Email address: sophie.domejean@uca.fr Refereed Paper. Accepted 1 June 2020 https://doi.org/10.1038/s41415-020-2316-x BRITISH DENTAL JOURNAL | ONLINE PUBLICATION | NOVEMBER 26 2020 1 RESEARCH © The Author(s), under exclusive licence to British Dental Association 2020