New Preventive Strategy against Oral Biofilm Formation in Caries-Active Children: An In Vitro Study

Area of Science:

• Microbiology
• Oral Health
• Bacterial Communication

Background:

• Quorum sensing (QS) regulates bacterial biofilm formation, crucial in cariogenic dental plaque.
• Quorum quenching (QQ) inhibits QS, but its impact on oral biofilm taxonomy is understudied.
• Understanding QQ's effect on polymicrobial oral biofilms is vital for developing new therapeutic strategies.

Purpose of the Study:

• To investigate the effect of the quorum quenching lactonase Aii20J on the biomass and taxonomic composition of in vitro oral biofilms.
• To assess whether Aii20J treatment alters the bacterial community structure in oral biofilms.
• To explore the potential of QQ as a strategy to modulate oral biofilm homeostasis.

Main Methods:

• Collected supragingival plaque from caries-free and caries-active children.
• Cultured in vitro oral polymicrobial biofilms.
• Applied the quorum quenching lactonase Aii20J to treated biofilms.
• Quantified biomass using crystal violet assays.
• Analyzed taxonomic composition via 16S rRNA gene amplicon sequencing.

Main Results:

• Aii20J treatment significantly reduced oral biofilm biomass.
• No significant changes in bacterial composition were observed at the genus level.
• Aii20J treatment increased the relative abundance of Streptococcus cristatus and Streptococcus salivarius at the species level.
• These increased species possess pH-buffering enzymes, suggesting a potential mechanism for counteracting cariogenic conditions.

Conclusions:

• Quorum quenching using Aii20J demonstrates biofilm-modulating capabilities in oral polymicrobial communities.
• QQ treatment can selectively promote the growth of beneficial oral bacteria.
• QQ offers a promising avenue for developing novel strategies to restore homeostasis in dysbiotic oral ecosystems and combat dental caries.