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Abstract

Dental caries, a widespread global health problem, results from oral microbiome dysbiosis dominated by acidogenic pathogens like Streptococcus mutans. Conventional preventive methods, such as fluoride and antimicrobial rinses, often lack specificity and can disrupt beneficial microbes. Probiotics are live, health-promoting bacteria or yeasts commonly found in foods such as yogurt or in dietary supplements. They help restore microbial balance and have emerged as a promising strategy for caries management. This review explores the mechanisms, efficacy, and clinical applications of probiotics in caries prevention. Specific strains such as Lactobacillus reuteri, Lactobacillus rhamnosus, and Streptococcus salivarius inhibit cariogenic bacteria through competitive exclusion, acidity modulation via arginine metabolism, and production of antimicrobial compounds like reuterin and bacteriocins. Clinical trials show that probiotic lozenges, gums, and dairy products reduce Streptococcus mutans counts and caries incidence in both children and adults. Challenges remain in optimizing strain selection, delivery methods, and ensuring long-term efficacy. Innovations include engineered probiotics with enhanced antimicrobial activity and synbiotics that combine probiotics with prebiotic fibers to improve colonization. While probiotics provide a safe, non-invasive adjunct to traditional approaches, further large-scale, well-designed longitudinal studies are essential to standardize protocols and understand their ecological effects on the oral microbiome. In summary, integrating probiotics into personalized oral care has the potential to revolutionize caries prevention by addressing microbial dysbiosis directly, shifting the focus from pathogen elimination to promoting a balanced microbiome. This highlights the significance of probiotics in supporting oral and dental health and potentially reducing the prevalence of caries worldwide.

Keywords

caries prevention probiotics

Introduction

Dental caries, commonly referred to as tooth decay, is among the most widespread chronic diseases globally, impacting approximately 2.5 billion individuals, including 514 million children with untreated cavities in their primary teeth. Recognized by the World Health Organization as a major global health burden, caries arises from a complex interplay of factors, including cariogenic biofilms, frequent sugar consumption, insufficient fluoride exposure, and compromised salivary function.^1,2 Caries is fundamentally a biofilm-driven disease caused by acid-producing and acid-tolerant bacteria, such as Streptococcus mutans (S. mutans) and Lactobacillus species, which ferment dietary carbohydrates into organic acids. These acids demineralize the enamel and dentin, leading to cavitation, pain, and, if untreated, systemic infections or tooth loss.^3–6 The economic impact is staggering, with global treatment costs exceeding USD 442 billion annually, underscoring the urgent need for effective, accessible prevention strategies.⁷

Traditional approaches to caries prevention have long centered on fluoride, antimicrobial agents, and dietary modifications.⁸ Fluoride,⁹ the cornerstone of caries management, enhances remineralization and inhibits demineralization by forming acid-resistant fluorapatite. However, its efficacy is limited in populations with poor access or high sugar intake, and excessive use risks dental fluorosis. Antimicrobials like chlorhexidine¹⁰ mouth rinses target pathogenic bacteria but lack specificity, indiscriminately disrupting commensal microbes critical for oral homeostasis. Dietary interventions, such as reducing free sugar consumption, face challenges in compliance due to the ubiquity of processed foods and socioeconomic disparities. Crucially, these strategies often fail to address the root cause of caries: dysbiosis in the oral microbiome.¹¹ A healthy oral cavity hosts over 700 microbial species in a balanced ecosystem, but frequent sugar exposure and poor hygiene shift this equilibrium toward acid-producing, acid-tolerant pathogens. This dysbiotic state perpetuates a low-pH environment, favoring enamel dissolution and biofilm maturation. Thus, there is growing recognition that sustainable caries prevention requires therapies that restore microbial harmony rather than merely suppressing symptoms.^12,13

Probiotics consist of live bacteria or yeasts present in certain foods, such as yogurt, and in dietary supplements, which help sustain a healthy microbial balance within the body. When consumed in adequate quantities, these microorganisms confer health benefits to the host. Increasingly, probiotics are recognized as a promising method to reestablish microbial equilibrium and combat dental caries by restoring the natural balance of the oral environment. Originating from the Greek term “pro bios,” meaning “for life,” the concept was first established in gut health research where specific strains like Lactobacillus and Bifidobacterium were shown to enhance digestion and immune function. Building upon this knowledge, probiotics have been applied to oral health to address microbial imbalance (dysbiosis) by introducing beneficial bacteria that inhibit pathogens, regulate oral pH, and produce antimicrobial agents. Common probiotic sources include fermented foods such as kefir, kimchi, and yogurt, along with supplements like gums, lozenges, and powders. This review focuses on the role of probiotics in preventing caries, discussing their underlying mechanisms, clinical effectiveness, challenges, and future directions.^14–17

Mechanisms of action

Unlike broad-spectrum antimicrobials, probiotics act through multiple mechanisms: (1) competitive exclusion, where they occupy adhesion sites on teeth and mucosa, blocking pathogen colonization; (2) Acidity (pH) modulation via arginine metabolism which generates ammonia to neutralize acidic plaque; (3) Antimicrobial Compound Production such as reuterin from Lactobacillus reuteri (L. reuteri), which selectively inhibits S. mutans; (4) Biofilm disruption where probiotics degrade pathogenic biofilms through enzymatic activity; and (5) Immunomodulation to improve the host’s defense against pathogens.^18–21 Figure 1 illustrates the mechanism of action of probiotics for the prevention of dental caries.

Figure 1.

Probiotic mechanisms in the prevention of dental caries.

Competitive exclusion

Probiotics prevent dental caries through competitive exclusion, a process where beneficial microbes outcompete cariogenic pathogens like S. mutans for ecological niches and resources.^22,23 In the oral cavity, saliva continuously deposits glycoproteins onto tooth surfaces, promoting microbial adhesion and helping maintain microbial balance by supplying nutrients and antimicrobial factors. Salivary glycoproteins, primarily mucins and proline-rich proteins, form the acquired pellicle by binding to adhesion receptors on tooth surfaces and mucosal tissues. Probiotics can bind to these same receptors, physically blocking pathogens from colonizing and thereby reducing their ability to form acid-producing biofilms.¹⁶ For instance, Lactobacillus strains and S. salivarius M18 occupy the same binding sites as S. mutans, limiting its attachment.^24–29 Additionally, probiotics consume dietary carbohydrates such as sugars that would otherwise fuel acidogenesis by pathogens, further starving harmful bacteria.¹⁶ This dual action of occupying space and sequestering nutrients creates an unfavorable environment for acidogenic microbes, lowering plaque acidity and enamel demineralization. Competitive exclusion thus rebalances the oral microbiome, offering a targeted, ecological strategy to disrupt caries pathogenesis.^30–32

Acidity modulation

Probiotics counteract the acidic environment driving caries by modulating plaque pH through metabolic activity. Certain strains, like Streptococcus salivarius (S. salivarius) M18 and L. reuteri, metabolize arginine, an amino acid in saliva, into ammonia via the arginine deiminase pathway.^26,33–37 Ammonia acts as a base, neutralizing organic acids produced by cariogenic bacteria like S. mutans.³⁸ Other probiotics (i.e. Streptococcus dentisani (S. dentisani), L. reuteri) generate non-acidic byproducts, such as hydrogen peroxide or buffering agents, which help raise the local pH. Hydrogen peroxide can inhibit acid-producing bacteria, reducing overall acid production, while buffering acids neutralize the acids in the environment. Together, these actions contribute to increasing the local pH, creating conditions less favorable for enamel demineralization.^39,40 By maintaining a neutral or alkaline oral environment, probiotics disrupt the cycle of enamel dissolution, inhibit acid-tolerant pathogens, and promote remineralization.^15,32,41,42 This pH modulation not only reduces immediate acid damage but also reshapes the microbial community by suppressing acidogenic and aciduric bacteria, such as S. mutans, while promoting the growth of acid-sensitive commensals like Streptococcus sanguinis (S. sanguinis) and Actinomyces naeslundii (A. naeslundii). Such targeted pH control offers a natural and sustainable strategy to prevent caries without disrupting the overall oral ecology.⁴³

Antimicrobial compound production

Probiotics combat dental caries by producing antimicrobial compounds that selectively inhibit cariogenic pathogens. Strains like L. reuteri synthesize reuterin, which is a broad-spectrum antimicrobial agent that disrupts S. mutans biofilm formation and viability.⁴⁴ Similarly, S. salivarius M18 secretes bacteriocin-like inhibitory substances that specifically target acid-producing bacteria (i.e. S. mutans) while sparing commensal species. These compounds weaken pathogenic biofilms by damaging cell membranes, inhibiting enzyme activity, or interfering with quorum sensing.³⁶ Additionally, some probiotics (i.e. L. reuteri, S. sanguinis) generate hydrogen peroxide or organic acids with selective toxicity, creating an inhospitable environment for acid-tolerant pathogens. By producing targeted antimicrobials, probiotics reduce the dominance of caries-causing microbes without indiscriminately harming beneficial oral flora.⁴⁵ This precision preserves microbial balance, curbs acidogenesis, and supports a healthier oral ecosystem, making antimicrobial production a critical, pathogen-specific strategy in caries prevention.

Biofilm disruption

Probiotics combat dental caries by disrupting pathogenic biofilms, the structured microbial communities driving enamel demineralization. Beneficial strains like S. salivarius K12 and Lactobacillus paracasei (L. paracasei) interfere with biofilm formation through competitive adhesion, occupying binding sites on tooth surfaces to block colonization by cariogenic pathogens such as S. mutans.^46,47 Additionally, probiotics (i.e. S. salivarius K12) secrete enzymes such as dextranase. These enzymes can degrade the extracellular polysaccharide matrix and destabilize biofilm architecture. Some strains produce surfactants or antimicrobial peptides, such as bacteriocins weaken bacterial cell membranes, causing biofilm detachment. By disrupting quorum sensing (a bacterial communication system that regulates virulence, biofilm formation, and acid production), probiotics effectively inhibit communication among pathogens, thereby reducing their virulence and acidogenic activity. Specific strains, such as L. reuteri and Bacillus subtilis, produce quorum-quenching molecules like reuterin and fengycins, which degrade signaling molecules (autoinducers) or block their receptors. This disruption suppresses pathogenic biofilm development, diminishes acid production, and promotes a healthier microbial balance. The multifaceted interference not only reduces biofilm viability but also helps restore a balanced oral microbiome, limiting plaque accumulation and acidogenesis. Such targeted biofilm modulation highlights probiotics as a promising, non-invasive strategy for preventing caries progression.^48–50

Immunomodulation

Probiotics prevent dental caries by modulating host immune responses to enhance oral defense mechanisms. Strains like Lactobacillus rhamnosus (L. rhamnosus) and S. salivarius stimulate mucosal immunity, boosting secretory Immunoglobulin A production to neutralize S. mutans and block its adhesion.^51,52 Probiotics engage with epithelial cells and immune mediators to modulate host immune responses by enhancing the production of anti-inflammatory cytokines such as Interleukin-6 and suppressing pro-inflammatory signals like Tumor Necrosis Factor (TNF) through inhibition of NF-κB signaling and modulation of toll-like receptors (TLRs). This immune regulation reduces chronic inflammation, which can impair salivary gland function and increase permeability of gingival and enamel-adjacent tissues, conditions that weaken enamel and increase susceptibility to acid attack. Certain strains, including L. rhamnosus GG and S. salivarius K12, also upregulate antimicrobial peptides like human β-defensin-2, reinforcing the epithelial barrier and inhibiting pathogens such as S. mutans and P. gingivalis. By balancing immune responses, probiotics help mitigate dysbiosis, inhibit acidogenic biofilm formation, and support tissue repair. This dual mechanism, combining direct antimicrobial activity with immune enhancement, offers a comprehensive, non-invasive approach to maintaining a caries-resistant oral ecosystem.^52–55

Key probiotic strains and evidence

The three common probiotic strains include L. reuteri, S. salivarius, and Bifidobacterium DN-173 010. Table 1 summarizes their antimicrobial mechanisms and research evidence of probiotics in caries prevention.

Table 1.

Antimicrobial mechanisms and research evidence of key probiotics in caries prevention.

Probiotic strains	Antimicrobial mechanism	Research evidence
L. reuteri	Produces reuterin, a broad-spectrum antimicrobial	Daily L. reuteri supplementation in infancy reduced caries and gingivitis at age 9, with 82% caries-free compared to 58% in controls.⁵⁶
S. salivarius M18 (S M18)	Competes with S. mutans and secretes bacteriocins like salivaricin	A 7-day S. salivarius M18 regimen reduced S. mutans levels by increasing salivary pH and buffering capacity, thereby lowering caries risk.⁵⁷
BifidobacteriumDN-173 010	Enhances innate immunity and oral ecology	Yogurt with Bifidobacterium DN-173 010 significantly lowered mutans streptococci levels, reducing caries risk.⁵⁸

Lactobacillus reuteri

Lactobacillus reuteri demonstrates significant potential in caries prevention through multifaceted mechanisms. This probiotic strain inhibits S. mutans, a primary cariogenic pathogen, by producing reuterin, a broad-spectrum antimicrobial compound that disrupts biofilm formation and bacterial viability.⁵⁶ Additionally, L. reuteri metabolizes arginine via the arginine deiminase pathway, generating ammonia to neutralize acidic plaque pH, thus counteracting enamel demineralization.⁵⁹ Its ability to competitively adhere to dental surfaces blocks S. mutans colonization, reducing pathogenic biofilm accumulation. Furthermore, L. reuteri modulates host immune responses by enhancing secretory Immunoglobulin A production, strengthening mucosal defenses against pathogen invasion.⁶⁰ By combining antimicrobial action, acidity (pH) modulation, competitive exclusion, and immunomodulation, L. reuteri rebalances the oral microbiome, curbing acidogenesis and promoting a caries-resistant environment. Clinical studies support its efficacy in reducing S. mutans counts and caries risk, positioning it as a promising probiotic for targeted oral health strategies.^61,62

Streptococcus salivarius

Streptococcus salivarius, particularly strains like M18 and K12, is a promising probiotic for caries prevention due to its multifaceted actions. It produces bacteriocin-like inhibitory substances (BLIS) that selectively target cariogenic pathogens such as S. mutans, disrupting their biofilm formation and acid production.⁵⁷ S. salivarius also metabolizes arginine via the arginine deiminase pathway, generating ammonia that helps neutralize acidic plaque pH and inhibit enamel demineralization.^63,64 Additionally, it competes with harmful bacteria for adhesion sites on tooth surfaces, limiting their ability to colonize.³⁶ Certain strains of S. salivarius produce enzymes such as dextranase that degrade extracellular polysaccharides, disrupting the stability of cariogenic biofilms.⁶⁵ Moreover, S. salivarius enhances oral immunity by stimulating secretory Immunoglobulin A, which blocks pathogen adherence and promotes mucosal defence.⁶⁶ Clinical studies have demonstrated its effectiveness in reducing S. mutans levels and caries risk, positioning it as a natural, targeted strategy to restore microbial balance and promote a caries-resistant oral environment.^36,57

Bifidobacterium DN-173 010

Bifidobacterium DN-173 010, a probiotic strain widely used for gastrointestinal health, shows promising potential in caries prevention. Although direct clinical evidence is limited, it may inhibit S. mutans, a main cariogenic bacterium, by competing for adhesion sites and producing antimicrobial substances.^58,67 Additionally, it can modulate the oral microbiota by reducing acidogenic species and promoting microbial balance, which helps decrease plaque accumulation and acid production, key factors in enamel demineralization.^68,69 This strain’s ability to adhere to oral tissues further limits pathogen colonization.⁷⁰ Its immunomodulatory properties may also reduce oral inflammation and caries risk. While strains like L. rhamnosus have more extensive oral health documentation, Bifidobacterium DN-173 010 remains a promising candidate. Potential delivery systems include dairy products, chewing gums, and oral care formulations, though further clinical trials are necessary to validate their specific role in caries prevention.^71–73

Delivery vehicles and clinical efficacy

The success of probiotics for the prevention of dental caries hinges on two essential factors: delivery systems and clinical validation. Reliable carriers are crucial to ensure that probiotics remain viable, successfully colonize the oral cavity, and exert their intended effects at the target site. Equally important is strong clinical evidence demonstrating their practical benefits. Addressing formulation challenges and establishing standardized protocols are key steps toward realizing the full potential of probiotics as a scalable, microbiome-friendly strategy for caries prevention.

Delivery vehicles

Common delivery vehicles included dairy products,⁷⁴ lozenges/gums,^75,76 and bioactive films.⁷⁷ Dairy products include yogurt and milk. They remain popular but may contain sugars that counteract benefits. Lozenges and gums provide prolonged oral retention; acidity-stable formulations improve probiotic viability. Bioactive Films are edible films with probiotics and prebiotics like xylitol to enhance targeted delivery.^78,79

Clinical efficacy

A meta-analysis of 19 randomized controlled trials evaluated the effects of probiotics on dental caries-related outcomes in children and adolescents. While probiotics likely reduced S. mutans counts (moderate-quality evidence), they did not significantly impact dental caries rates, Lactobacillus levels, plaque index, gingival index, or salivary acidity (pH), indicating their benefits may be mostly limited to lowering S. mutans.⁸⁰ In contrast, a randomized, double-blind, placebo-controlled study evaluated the effects of Lactobacillus rhamnosus GG (LGG) delivered through milk on dental caries in 594 children aged 1 to 6 years over 7 months. Children who consumed LGG milk showed significantly fewer caries and lower mutans streptococci counts, especially those aged 3 to 4 years. LGG consumption was linked to a reduced risk of caries (OR = 0.56, p = 0.01), indicating a promising benefit for children’s oral health.⁸¹ However, heterogeneity in probiotic strains, dosages, and study lengths make direct comparisons difficult, and the transient nature of colonization often necessitates continuous supplementation.

Interplay between delivery and efficacy

Probiotics have demonstrated the ability to reduce S. mutans, a crucial contributor to dental caries, yet their effectiveness can vary depending on the delivery method. Studies comparing probiotic lozenges, sachets, and beverages have shown that all forms can significantly decrease S. mutans levels, with lozenges often providing the greatest reduction due to better retention and targeted release.^82,83 Furthermore, synbiotic combinations of prebiotics and probiotics have emerged as a promising approach for oral health. Certain prebiotics, such as arabinose, xylose, and xylitol, promote the growth and activity of beneficial Lactobacillus strains, which have been shown to inhibit pathogenic oral microbes like Candida albicans, S. mutans, and Porphyromonas gingivalis.^84,85 Overall, these findings suggest that optimizing the formulation and delivery of probiotics, particularly when combined with effective prebiotics, is essential to maximize their therapeutic credibility of the prevention of dental caries and the management of oral infections.

Application of probiotics in caries prevention and their limitations

The utilization of probiotics for dental caries prevention represents a paradigm shift in oral health strategies, targeting microbial dysbiosis through ecological modulation rather than broad-spectrum antimicrobial action. Probiotics such as L. reuteri, L. rhamnosus, and S. salivarius have demonstrated efficacy in clinical trials, primarily by competitively inhibiting cariogenic pathogens like S. mutans, modulating oral pH via arginine metabolism, and secreting antimicrobial agents (e.g. reuterin, bacteriocins). These mechanisms collectively reduce acidogenicity, a critical factor in enamel demineralization.^16,86 Delivery vehicles such as lozenges, gums, and dairy products enhance localized colonization, with studies reporting significant reductions in S. mutans counts and caries incidence in both pediatric and adult populations.¹⁸ For instance, trials using L. rhamnosus GG-fortified milk in children showed a significant reduction in caries risk, underscoring their potential as adjunctive therapies.⁸¹ However, the application of probiotics is not without contraindications. Immunocompromised individuals, including those undergoing chemotherapy or with HIV/AIDS, may face risks of bacteraemia or systemic infections due to bacterial translocation from oral or gut microbiota, albeit rare.⁸⁷ Strain specificity is critical, as certain Lactobacillus species, such as Lactobacillus acidophilus (L. acidophilus), possess acidogenic traits that could inadvertently exacerbate caries. Furthermore, dairy-based probiotics pose allergy risks for lactose-intolerant individuals, necessitating non-dairy alternatives like lozenges. Long-term safety remains underexplored, particularly in vulnerable groups such as pregnant women or infants, where microbial colonization dynamics are complex. Overuse of probiotics might theoretically disrupt niche oral ecosystems, though current evidence suggests they are more selective than traditional antimicrobials.^88–90

Challenges persist in optimizing strain selection, delivery systems, and sustainability. Engineered probiotics with enhanced antimicrobial properties and synbiotics (combining probiotics with prebiotics) represent promising innovations to improve colonization and efficacy. Yet, heterogeneity in trial designs, varying strains, dosages, and durations complicates protocol standardization. While probiotics are generally safe, their integration into mainstream care requires addressing these gaps through large-scale longitudinal studies. Clinicians must weigh benefits against contraindications, ensuring strain suitability and patient-specific factors are considered. In summary, probiotics offer a microbiome-friendly alternative to conventional caries prevention, aligning with personalized medicine trends. However, their safe and effective use demands rigorous strain validation, tailored delivery methods, and heightened awareness of contraindications. Future research should prioritize ecological impact assessments and standardized guidelines to maximize therapeutic potential while mitigating risks.

Challenges and future research

Despite this promise, probiotics face challenges that hinder widespread adoption. Effects are strain-specific, and poorly formulated products may lack viability or fail to colonize the oral niche. For example, some Lactobacillus strains, such as L. acidophilus, may paradoxically exacerbate caries by producing excess lactic acid. Delivery vehicles also impose challenges use of probiotics for caries prevention.⁹¹ Dairy-based probiotics risk cariogenicity if sweetened, while lozenges and gums are designed to ensure prolonged oral retention. Long-term ecological impacts remain understudied, as continuous probiotic use could theoretically reduce microbial diversity. Safety concerns, though rare, include bacteremia in immunocompromised individuals.^92,93 Regulatory gaps further complicate standardization, with commercial products often mislabeled or containing insufficient viable cells.^94,95 Table 2 summarizes the challenges and precautions of probiotics use for caries prevention.

Table 2.

Challenges and precautions of probiotics use for caries prevention.

Challenges	Precautions
Strain specificity ^96,97	Benefits are strain-dependent; L. acidophilus may exacerbate caries risk by producing excess acid.
Ecological impact ⁹⁸	Long-term use may alter oral microbiota diversity; monitoring the ecological impact of probiotics is essential.
Safety issues ⁹⁹	Lack of standardized guidelines for probiotic dosing and quality control. Rare risks include bacteremia in immunocompromised individuals.

Advancements in synthetic biology and personalized medicine offer promising strategies for probiotic-based caries prevention. These include CRISPR-engineered probiotics with enhanced antimicrobial activity, synbiotics with prebiotics like xylitol, and personalized formulations tailored to individual microbiome profiles. Biofilm engineering is also progressing, with modified probiotic strains producing targeted peptides (e.g. nisin)¹⁰⁰ to selectively disrupt cariogenic biofilms and support oral health (Table 3).

Table 3.

Research and innovations of probiotics use for caries prevention.

Research	Innovations
Engineered probiotics ¹⁰¹	Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-edited S. salivarius strains with enhanced bacteriocin production target S. mutans selectively.
Synbiotics ¹⁰²	Probiotics, prebiotics, and synbiotics are promising antibiotic alternatives in livestock, enhancing growth, health, and gut microbiota balance.
Personalized probiotics ¹⁰³	Personalized probiotics outperformed commercial ones in reducing inflammation and colonic damage in a mouse colitis model.
Biofilm engineering ¹⁰⁴	Nanofiber-embedded probiotics provide sustained release and effectively inhibit periodontal pathogens for local treatment.

Conclusion

Probiotics represent a paradigm shift in caries prevention by targeting microbial ecology rather than solely suppressing pathogens. While clinical evidence supports their efficacy, challenges related to strain optimization, delivery methods, and long-term safety remain. Monitoring the ecological impact of probiotic use is essential to ensure that introduced strains do not disrupt the natural oral microbiome or trigger unintended microbial shifts. Emerging evidence highlights that personalized probiotics, tailored to an individual’s unique microbial and inflammatory profile, may outperform generic commercial formulations in restoring microbial balance and reducing dysbiosis. By selectively inhibiting acidogenic pathogens and fostering a less acidic environment, probiotics promote the growth of acid-sensitive commensals, such as S. sanguinis, thereby supporting a healthier and more stable oral ecosystem. Future research should prioritize engineered strains, personalized regimens, and ecological monitoring to fully harness the potential of probiotics. Integrating these advances with traditional preventive strategies could pave the way for holistic, microbiome-centered oral care, ultimately reducing the global burden of dental caries.

Footnotes

ORCID iDs

Mohammed Zahedul Islam Nizami

Chun Hung Chu

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

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Probiotics for caries prevention: A narrative review

Abstract

Keywords

Introduction

Mechanisms of action

Competitive exclusion

Acidity modulation

Antimicrobial compound production

Biofilm disruption

Immunomodulation

Key probiotic strains and evidence

Lactobacillus reuteri

Streptococcus salivarius

Bifidobacterium DN-173 010

Delivery vehicles and clinical efficacy

Delivery vehicles

Clinical efficacy

Interplay between delivery and efficacy

Application of probiotics in caries prevention and their limitations

Challenges and future research

Conclusion

Footnotes

ORCID iDs

Funding

Declaration of conflicting interests

References