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Red fluorescent biofilm: the thick, the old, and the cariogenic.

ABSTRACT: BACKGROUND:Some dental plaque fluoresces red. The factors involved in this fluorescence are yet unknown. OBJECTIVE:The aim of this study was to assess systematically the effect of age, thickness, and cariogenicity on the extent of red fluorescence produced by in vitro microcosm biofilms. DESIGN:The effects of biofilm age and thickness on red fluorescence were tested in a constant depth film fermentor (CDFF) by growing biofilms of variable thicknesses that received a constant supply of defined mucin medium (DMM) and eight pulses of sucrose/day. The influence of cariogenicity on red fluorescence was tested by growing biofilm on dentin disks receiving DMM, supplemented with three or eight pulses of sucrose/day. The biofilms were analyzed at different time points after inoculation, up to 24 days. Emission spectra were measured using a fluorescence spectrophotometer (?exc405 nm) and the biofilms were photographed with a fluorescence camera. The composition of the biofilms was assessed using 454-pyrosequecing of the 16S rDNA gene. RESULTS:From day 7 onward, the biofilms emitted increasing intensities of red fluorescence as evidenced by the combined red fluorescence peaks. The red fluorescence intensity correlated with biofilm thickness but not in a linear way. Biofilm fluorescence also correlated with the imposed cariogenicity, evidenced by the induced dentin mineral loss. Increasing the biofilm age or increasing the sucrose pulsing frequency led to a shift in the microbial composition. These shifts in composition were accompanied by an increase in red fluorescence. CONCLUSIONS:The current study shows that a thicker, older, or more cariogenic biofilm results in a higher intensity of red fluorescence.

SUBMITTER: Volgenant CM

PROVIDER: S-EPMC4826460 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Red fluorescent biofilm: the thick, the old, and the cariogenic.

Volgenant Catherine M C CM Hoogenkamp Michel A MA Buijs Mark J MJ Zaura Egija E Ten Cate Jacob M JM van der Veen Monique H MH

Journal of oral microbiology 20160407

<h4>Background</h4>Some dental plaque fluoresces red. The factors involved in this fluorescence are yet unknown.<h4>Objective</h4>The aim of this study was to assess systematically the effect of age, thickness, and cariogenicity on the extent of red fluorescence produced by in vitro microcosm biofilms.<h4>Design</h4>The effects of biofilm age and thickness on red fluorescence were tested in a constant depth film fermentor (CDFF) by growing biofilms of variable thicknesses that received a constan ...[more]

PMID: 27060056

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Red fluorescent biofilm: the thick, the old, and the cariogenic.

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Red fluorescent biofilm: the thick, the old, and the cariogenic.

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