Natural Compounds in Oral Microbiota Modulation and Caries Prevention: A Systematic Review

Background/Objectives: Certain components of natural products help maintain the oral microbiota balance, thereby promoting oral health. This study aimed to identify natural components with anticariogenic properties by analyzing evidence from in vivo studies. Methods: A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was performed across multiple databases and included English-language studies published between 2013 and 2025. The review included intervention and comparative studies that examined the effects of dietary habits involving natural components in participants of any age, with or without dental caries. Results: A total of 77 studies were included in the review, most of which were clinical trials conducted in pediatric populations. To assess the impact of the interventions, most studies measured outcomes such as Streptococcus mutans levels, dental caries incidence, and salivary pH, among other parameters. The most frequently studied components included probiotics, plant extracts, sugar substitutes, propolis, arginine, dairy products, among others. Significant effects were most reported on biological risk factors (72.8%). In addition, 16.9% of the studies reported a statistically significant reduction in clinically diagnosed dental caries. Conclusions: This review identified preliminary evidence suggesting that certain natural compounds may play a role in modulating cariogenic factors. However, further high-quality studies are needed to strengthen the evidence base and confirm these findings. The protocol for this review was registered on the Open Science Framework platform.