title: Detection of non-cavitated occlusal caries with impedance spectroscopy and laser fluorescence: an in vitro study.
abstract: OBJECTIVE
  To evaluate the performance of an impedance spectroscopy technology for detecting non-cavitated occlusal caries lesions in permanent teeth in vitro. The method was compared with a commonly used laser fluorescence device and validated against histology.
  
  
  METHODS
  A non-cavitated sample of 100 extracted posterior teeth was randomly selected and assessed for caries on enamel and dentin level with aid of CarioScan PRO (ACIS) and DIAGNOdent pen (LF pen) by three examiners. After the measurements, the extension of the lesion was histologically determined as gold standard. Sensitivity, specificity, accuracy and receiver-operating curves were calculated. Intra- and inter-examiner reproducibility was expressed by intra class correlation coefficients.
  
  
  RESULTS
  The histological caries prevalence was 99% and 41% exhibited dentin caries. The ACIS technique displayed high specificities but almost negligible sensitivities at readings >50. A similar pattern was noted for the LF pen at readings >30. The intra- and inter-examiner reproducibility varied between 0.47 and 0.98 and the values were generally lower for the ACIS technique than for the LF pen. The inter-examiner agreement reached excellent levels with both methods.
  
  
  CONCLUSIONS
  In vitro,the ACIS technique showed a low ability to disclose occlusal caries lesions in the enamel and/or dentin of non-cavitated permanent molars. However, further in vivo studies of permanent occlusal surfaces are needed to mirror the clinical situation.
authors.affiliation: Department of Odontology, Section for Cariology & Endodontics and Pediatric Dentistry & Clinical Genetics, Faculty of Health Sciences, University of Copenhagen, Denmark.
authors.forename: Diana
authors.initials: D
authors.lastname: Mortensen
authors.affiliation: Department of Odontology, Section of Oral Rehabilitation, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
authors.forename: Katrine
authors.initials: K
authors.lastname: Dannemand
authors.affiliation: Department of Odontology, Section for Cariology & Endodontics and Pediatric Dentistry & Clinical Genetics, Faculty of Health Sciences, University of Copenhagen, Denmark.
authors.forename: Svante
authors.initials: S
authors.lastname: Twetman
authors.affiliation: Department of Odontology, Section for Cariology & Endodontics and Pediatric Dentistry & Clinical Genetics, Faculty of Health Sciences, University of Copenhagen, Denmark.
authors.forename: Mette Kirstine
authors.initials: MK
authors.lastname: Keller
keywords: Caries detection; impedance spectroscopy; laser fluorescence; molar teeth.