Effect of CPP-ACP and APF on Streptococcus mutans biofilm: A laboratory study

Area of Science:

• Biomaterials science
• Microbiology
• Dental research

Background:

• Streptococcus mutans (S. mutans) is a primary cariogenic bacterium.
• Dental caries prevention strategies often involve agents that inhibit bacterial growth and promote remineralization.
• Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and acidulated phosphate fluoride (APF) are commonly used agents in caries management.

Purpose of the Study:

• To evaluate the impact of CPP-ACP and APF on S. mutans viability.
• To assess the effects of these agents on the structural integrity of S. mutans biofilms.
• To analyze elemental changes on hydroxyapatite (HA) surfaces after exposure to CPP-ACP and APF.

Main Methods:

• Hydroxyapatite discs were treated with CPP-ACP, APF, or a combination (CPP-ACP+APF), with uncoated discs serving as controls.
• Treated discs were incubated with human saliva and S. mutans for 24 hours.
• Bacterial growth, biofilm structure (CLSM), and elemental composition of HA surfaces (EDS) were analyzed.

Main Results:

• Both APF and CPP-ACP+APF significantly reduced S. mutans bacterial counts compared to the control group (P<0.05).
• Biofilm structure remained consistent across all tested groups.
• No significant differences in oxygen, fluorine, sodium, phosphorus, or calcium content were found on HA surfaces, though APF-treated surfaces showed higher fluoride levels.

Conclusions:

• APF and CPP-ACP+APF demonstrate antimicrobial efficacy against S. mutans.
• While these agents affect bacterial viability, they do not significantly alter biofilm structure or the elemental composition of hydroxyapatite surfaces under the tested conditions.
• Further research may explore the long-term effects and synergistic interactions of these agents in a more complex oral environment.