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Updated: Mar 13, 2026
09:44
Oral Biofilm Analysis of Palatal Expanders by Fluorescence In-Situ Hybridization and Confocal Laser Scanning Microscopy
Published on: October 20, 2011
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A Critical Role for Extracellular DNA in Dental Plaque Formation
N Rostami1, R C Shields1, S A Yassin1
11 School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK.
Journal of Dental Research
|October 23, 2016
Summary
Extracellular DNA (eDNA) is a key structural component in natural oral biofilms like dental plaque. Degrading eDNA with NucB enzyme inhibits biofilm formation and reduces bacterial diversity, suggesting eDNA is a promising target for oral health interventions.
Area of Science:
- Microbiology
- Oral Biology
- Biotechnology
Background:
- Extracellular DNA (eDNA) stabilizes monospecies biofilms in vitro.
- Its role in natural, mixed-species oral biofilms remains less understood.
Purpose of the Study:
- To investigate the presence and significance of eDNA in natural oral biofilms.
- To assess the impact of eDNA degradation on oral biofilm formation and composition.
Main Methods:
- Developed fluorescent staining techniques for eDNA visualization using antibodies and YOYO-1 dye.
- Created in vitro oral biofilm microcosms using human saliva.
- Treated biofilms with the DNA-degrading enzyme NucB from Bacillus licheniformis.
Main Results:
- Detected eDNA distributed throughout microcosm biofilms, particularly near cells.
- Confirmed eDNA presence in patient-derived dental plaque and implant biofilms.
- NucB treatment significantly inhibited biofilm accumulation and reduced bacterial species diversity, especially anaerobic proteolytic bacteria.
- NucB showed less effect on preformed biofilms.
Conclusions:
- eDNA is a common and important component of natural oral biofilms, including dental plaque and implant-associated biofilms.
- eDNA plays a crucial role in the early stages of oral biofilm development.
- Targeting eDNA with enzymes like NucB presents a potential strategy for controlling oral biofilm formation and associated diseases.
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