title: A preliminary investigation of a spectroscopic technique for the diagnosis of natural caries lesions.
abstract: OBJECTIVE
  To report the use of spectroscopic analysis of dental fluorescence excited with a blue InGaN laser diode operating at 405 nm.
  
  
  METHODS
  The spectra resulting from three classifications of smooth surface non-cavitated caries lesions (dull, shiny, brown) with 20 samples in each group were examined using the ratio of integrated fluorescence intensity in two spectral bands.
  
  
  RESULTS
  All lesions demonstrated spectra which were significantly different from sound tooth structure. As expected, the 'brown' lesions demonstrated a significantly different spectral profile from the two white spot lesion classifications. Dull and shiny lesions had significantly different spectral measurements when examining the ratio of the integrated fluorescence in spectral bands between 480-500 and 620-640 nm.
  
  
  CONCLUSIONS
  This method has application for detection of dental caries as well as demonstrating potential application to evaluate lesions which may represent different degrees of caries activity.
authors.affiliation: Departmento de Endodontia, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Adriana
authors.initials: A
authors.lastname: Ribeiro
authors.forename: Christel
authors.initials: C
authors.lastname: Rousseau
authors.forename: John
authors.initials: J
authors.lastname: Girkin
authors.forename: Andrew
authors.initials: A
authors.lastname: Hall
authors.forename: Ronald
authors.initials: R
authors.lastname: Strang
authors.forename: C
authors.initials: C
authors.lastname: John Whitters
authors.forename: Stephen
authors.initials: S
authors.lastname: Creanor
authors.forename: Anderson S L
authors.initials: AS
authors.lastname: Gomes
mesh_terms: D000704:Analysis of Variance; D003731:Dental Caries / Q000175:diagnosis*; D003732:Dental Caries Activity Tests; D003936:Diagnosis, Computer-Assisted; D005453:Fluorescence; D006801:Humans; D007834:Lasers; D012815:Signal Processing, Computer-Assisted; D013050:Spectrometry, Fluorescence