A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries progression: Positive or Negative impact?

Background: The interaction between Streptococcus mutans (S. mutans) and Veillonella species (Veillonella spp.) is unclear. This study aims to investigate the interaction between S. mutans and Veillonella spp. on caries development using systematic review. Methods: This systematic review was accorded to the guideline of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Three electronic databases, namely PubMed, Embase, and the Cochrane library, were used to conduct a systematic search for eligible studies from their inception until July 18, 2023. PROSPERO registration number was No. CRD42023445968. Results: We initially identified 4,774 articles. After eliminating duplicates and irrelevant articles, 11 studies met the inclusion criteria. The studies revealed important aspects of the relationship between S. mutans and Veillonella spp. in dental caries. One significant finding is that Veillonella spp. can affect the acid production capacity of S. mutans. Some studies indicate that Veillonella spp. can inhibit the acid production by S. mutans, potentially reducing the cariogenic process. Another aspect is the competition for substrates. Veillonella spp. utilize lactic acid, which is a by product of S. mutans metabolism, as a source of carbon. This metabolic interaction may decrease the availability of lactic acid for S. mutans, potentially influencing its cariogenic potential. Conclusions: This systematic review highlights the emerging evidence on the interaction between S. mutans and Veillonella spp. in dental caries. The findings suggest that Veillonella spp. can modulate the acid production, and substrate competition of S. mutans, potentially influencing the cariogenic process.