Table of Contents
Journal of Medical Engineering
Volume 2013, Article ID 161090, 9 pages
Research Article

Spectroscopic Detection of Caries Lesions

1Faculty of Technology, University of Vaasa, P.O. Box 700, 65101 Vaasa, Finland
2Dental Services of the City of Vaasa, Social and Health Administration, P.O. Box 241, 65101 Vaasa, Finland

Received 30 August 2012; Accepted 6 November 2012

Academic Editor: Hengyong Yu

Copyright © 2013 Mika Ruohonen et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Background. A caries lesion causes changes in the optical properties of the affected tissue. Currently a caries lesion can be detected only at a relatively late stage of development. Caries diagnosis also suffers from high interobserver variance. Methods. This is a pilot study to test the suitability of an optical diffuse reflectance spectroscopy for caries diagnosis. Reflectance visible/near-infrared spectroscopy (VIS/NIRS) was used to measure caries lesions and healthy enamel on extracted human teeth. The results were analysed with a computational algorithm in order to find a rule-based classification method to detect caries lesions. Results. The classification indicated that the measured points of enamel could be assigned to one of three classes: healthy enamel, a caries lesion, and stained healthy enamel. The features that enabled this were consistent with theory. Conclusions. It seems that spectroscopic measurements can help to reduce false positives at in vitro setting. However, further research is required to evaluate the strength of the evidence for the method’s performance.