Quantifying dental biofilm growth using cross-polarization optical coherence tomography

Lett Appl Microbiol. 2012 Jun;54(6):537-42. doi: 10.1111/j.1472-765X.2012.03243.x. Epub 2012 Apr 10.


Aims: Quantifying the ex vivo growth of complex multispecies dental biofilms using cross-polarization 1310-nm optical coherence tomography (CP-OCT) system was investigated.

Methods and results: Bacterial microcosms, which were derived from plaque samples of paediatric subjects, were incubated in a biofilm reactor system containing discs of different dental materials for 72 h with daily sucrose pulsing (5×). CP-OCT analysis of biofilm mass was validated with crystal violet (CV) assays at various growth stages of these complex biofilms. CP-OCT was able to filter out the back-reflected signals of water layers in the hydrated biofilm and allowed for direct biofilm quantification. The overall depth-resolved scattering intensity of the biofilm showed very strong positive correlation with CV assay quantification (Spearman's ρ = 0.92) during the growth phase of the biofilm.

Conclusion: CP-OCT was able to quantify the mass of the biofilm by measuring the overall depth-resolved scattering of the biofilm.

Significance and impact of the study: CP-OCT has the ability to nondestructively monitor biofilm growth and elucidate the growth characteristics of these microcosms on different dental material compositions.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Bacteria / growth & development*
  • Bacteriological Techniques
  • Biofilms / growth & development*
  • Bioreactors
  • Child
  • Culture Media
  • Dental Plaque / microbiology*
  • Humans
  • Tomography, Optical Coherence / methods*


  • Culture Media