Effect of tablets containing probiotic bacteria (Lactobacillus reuteri) on early caries lesions in adolescents: a pilot study

A comprehensive review of the application of probiotics and postbiotics in oral health

Oral diseases are among the most common diseases around the world that people usually suffer from during their lifetime. Tooth decay is a multifactorial disease, and the composition of oral microbiota is a critical factor in its development. Also, Streptococcus mutans is considered the most important caries-causing species. It is expected that probiotics, as they adjust the intestinal microbiota and reduce the number of pathogenic bacteria in the human intestine, can exert their health-giving effects, especially the anti-pathogenic effect, in the oral cavity, which is part of the human gastrointestinal tract. Therefore, numerous in vitro and in vivo studies have been conducted on the role of probiotics in the prevention of tooth decay. In this review, while investigating the effect of different strains of probiotics Lactobacillus and Bifidobacteria on oral diseases, including dental caries, candida yeast infections, periodontal diseases, and halitosis, we have also discussed postbiotics as novel non-living biological compounds derived from probiotics.

A Cross-Talk between Diet and the Oral Microbiome: Balance of Nutrition on Inflammation and Immune System's Response during Periodontitis

Over the last few decades, studies on the oral microbiome have increased awareness that the balance between the host and the microbial species that coexist in it is essential for oral health at all stages of life. However, this balance is extremely difficult to maintain, and many factors can disrupt it: general eating habits, sugar consumption, tobacco smoking, oral hygiene, and use of antibiotics and other antimicrobials. It is now known that alterations in the oral microbiota are responsible for developing and promoting many oral diseases, including periodontal disease. In this context, diet is an area for further investigation as it has been observed that the intake of particular foods, such as farmed animal meat, dairy products, refined vegetable oils, and processed cereals, affects the composition of the microbiota, leading to an increased representation of acid-producing and acid-tolerant organisms and periodontal pathogens. However, little is known about the influence of diet on the oral microbiome and the creation of a suitable microenvironment for the development of periodontal disease. The aim of the present study is to evaluate current knowledge on the role of diet in the oral dysbiosis underlying periodontal disease.

Efficacy of probiotics against dental caries in children: a systematic review and meta-analysis

Dental caries causes serious consequences and the financial burden of society especially in children with high morbidity rate. Here we carried out a meta-analysis to systematically evaluate the efficacy of probiotics against dental caries in children. Forty-three RCTs were eligible for this meta-analysis after searching the PubMed, Cochrane and Web of Science from the inception through October 2021. Pooled estimates demonstrated that treatment with probiotics significantly reduced noncavitated (dicdas2-6mft) (SMD = -0.18, 95% CI: -0.3 to -0.06, p = 0.002) and cavitated (dicdas5-6mft) carious lesions in children (SMD = -0.32, 95% CI: -0.5 to 0.14, p = 0.0004). Probiotics also reduced prevalence of noncavitated (dicdas2-6mft) carious lesions (RR = 0.8, 95% CI: 0.67 to-0.97, p = 0.02). Salivary Streptococcus mutans was declined after intervention (SMD = -1.17, 95% CI: -1.85 to -0.5, p = 0.0007), while Lactobacillus counts were upregulated (SMD = 1.19, 95% CI: 0.46-1.92, p = 0.001). However, no significant effects in total bacteria counts and salivary pH were observed. Our findings suggest that probiotics especially Lactobacillus could be a promising therapeutic strategy for clinical applications in children dental caries.

Prevention of Recurrent Childhood Caries with Probiotic Supplements: A Randomized Controlled Trial with a 12-Month Follow-Up

The aim of this study was to evaluate the effect of drops containing probiotic bacteria on the recurrence of dental caries in preschool children. The study employed a randomized, placebo-controlled, double-blinded design with two parallel arms. 38 preschool children were enrolled after comprehensive restorative treatment under general anesthesia or conscious sedation (baseline), and they were followed up after 6 and 12 months. Parents of children in the test group were instructed to give 5 daily drops containing two strains of Limosilactobacillus reuteri (DSM 17938 and ATCC PTA 5289) at bedtime. The placebo drops were identically composed but lacked bacteria. The duration of the intervention was 12 months. The primary endpoint was recurrence of new caries lesions on subject level (yes/no), and secondary endpoints were presence of dental plaque and gingivitis. We found high rate of recurrent moderate and extensive lesions after 12 months (67%) but there were no significant differences between the groups. We observed no beneficial effects on dental plaque or gingival inflammation. The findings were however uncertain and inconclusive due to lack of power, a consequence of the COVID-19 pandemic. ClinTrials.gov Identifier: (NCT04929340), June 18, 2021; retrospectively registered.

Probiotics as an Adjunct Therapy for the Treatment of Halitosis, Dental Caries and Periodontitis

Probiotics and prebiotics are popular among consumers worldwide as natural approaches to prevent gastrointestinal diseases. The effects of their consumption on the gastrointestinal system have been extensively investigated. Recently, the efficacy of probiotics and prebiotics has been evaluated against naturally developing microbiome imbalance in the human body, such as in the oral cavity, skin, female urogenital tract, and respiratory tract. This review examines the scientific data related to the effects of probiotics on the treatment of diseases occurring in the oral cavity. Probiotics can effectively prevent and treat some infectious diseases in the oral cavity, such as halitosis and periodontitis, and can reduce the development of dental caries and the concentration of harmful bacteria, according to clinical studies. The results of this meta-analysis also suggest the use of probiotics to treat halitosis and periodontitis. However, the evidence may be inconclusive due in part to the use of a wide range of probiotics, non-standardized study design, small population size, poor quality reports, and inconsistent data. Therefore, future studies should homogenize terms and definitions for primary and secondary outcomes, increase the number of volunteers/patients in in vitro tests and clinical studies, and include an evaluation of the combined use of pre- and probiotics.

Probiotics, Prebiotics, Synbiotics and Dental Caries. New Perspectives, Suggestions, and Patient Coaching Approach for a Cavity-Free Mouth

Probiotic therapy forms a new strategy for dental caries prevention. Probiotic microorganisms possess the ability to displace cariogenic microorganisms and colonize the oral cavity. They can produce various antimicrobial substances such as bacteriocins, bacteriocin-like peptides, lactic acid, and hydrogen peroxide. Dairy products may be ideal for probiotic administration in dental patients. Many other means have been proposed, primarily for those allergic to dairy components, such as capsules, liquid form, tablets, drops, lozenges, sweetened cakes, and ice creams. The last two forms can be used in a coaching approach for children and elderly patients who find it difficult to avoid sugary beverages in their daily routine and benefit from the suggestion of easy, cheap, and common forms of delicacies. In caries prevention, the concept of the effector strain is already considered an integral part of the contemporary caries cure or prevention strategy in adults. Adults, though, seem not to be favored as much as children at early ages by using probiotics primarily due to their oral microbiome’s stability. In this non-systematic review we describe the modes of action of probiotics, their use in the cariology field, their clinical potential, and propose options to prevent caries through a patient coaching approach for the daily dental practice.

The consumption of milk supplemented with probiotics decreases the occurrence of caries and the salivary concentration of hβD-3 in children

OBJECTIVES

This study evaluated the effect of milk supplemented with Lactobacillus rhamnosus SP1 on the occurrence of caries and the salivary concentration of human β-defensin-3 (hβD-3) in preschool children with high caries risk.

MATERIALS AND METHODS

A sample of 42 children was randomly assigned to two groups; children in the intervention group were given 150 mL of milk supplemented with 10⁷ CFU/mL of Lactobacillus rhamnosus SP1, while children in the control group were given standard milk, for 10 months. The occurrence of dental caries was assessed using the International Caries Detection and Assessment System (ICDAS), and the concentration of hβD-3 was measured in unstimulated saliva using an ELISA test at baseline and after the intervention.

RESULTS

There was an increase in the number of teeth with carious lesions (d_ICDAS2-6 mft) in the control group, and this increase was statistically significant (p = 0.0489). The concentration of hβD-3 in saliva from the intervention group decreased from 597.91 to 126.29 pg/mL (p = 0.0061), unlike in the control group, where no change in hβD-3 salivary concentration was found.

CONCLUSIONS

These findings showed that regular intake of probiotic-supplemented milk in preschool children with high caries risk decreased the occurrence of caries and the salivary levels of hβD-3.

CLINICAL RELEVANCE

Our results suggest the need for developing and implementing probiotic supplementation, as adjuvants to the conventional treatments for caries and allow to considerate the salivary levels of hβD-3 as markers of oral tissue homeostasis.

Effect of probiotic bacteria on oral Candida in head- and neck-radiotherapy patients: A randomized clinical trial

Objective

The aim of the study is to assess the effect of probiotic bacteria on oral Candida counts in cancer patients who are undergoing head- and neck-radiotherapy in a tertiary care center.

Study Design

The study was a randomized clinical trial including 90 patients who just completed head- and neck-radiotherapy.

Materials and Methods

Participants were randomly allocated into three equal sized groups, i.e., probiotics group, candid group, and combination groups. Oral rinse samples of the patients were collected before and after the intervention for the identification of Candida. The samples were incubated on Sabouraud's Dextrose Agar with Chloramphenicol at 37°C for 48 h, to assess the counts of colony-forming units/milliliter (CFU/ml) of Candida in saliva, and further on chrome agar plates to identify the Candida spp. Data were analyzed using mixed ANOVA to compare mean CFU/ml of Candida among three groups before and after the intervention.

Results

A total of 86 patients were included in the final analysis and there was a statistically significant reduction in mean Candida spp. Counts (CFU/ml) after intervention in all the three groups (P = 0.000) and significant reductions identified in both probiotic and combination therapy groups. Apart from reduction in Candida albicans, significant decrease in Candida glabrata and Candida tropicalis was observed after probiotics usage compared to other groups.

Conclusions

The present study suggests that probiotic bacteria were effective in reducing oral Candida spp which can be recommended alone or in combination with traditional antifungal agents for effective reduction in oral Candida in head- and neck-radiotherapy patients.

Enterococcus faecalis Is a Better Competitor Than Other Lactic Acid Bacteria in the Initial Colonization of Colon of Healthy Newborn Babies at First Week of Their Life

Initial colonization of human gut by bacteria is an important step in controlling its microbiota and health status. This study followed the initial colonization by lactic acid bacteria (LAB) in colon of new born babies through following its occurrence in their stool at first week of their life. The LAB occurrence in the neonates' stool was followed on MRS agar medium. The isolated LAB from male and female newborn babies of normal birth and cesarean section surgical delivery were molecular biologically identified by phylogenetic analysis of 16S rRNA gene sequence. From the 24 investigated newborn babies, three LAB taxa, Lactobacillaceae, Enterococcus, and Streptococcus, were detected in their stool at first week of their life. Lactobacillaceae represented 20.8% of total colonized LAB in newborn babies in the culture-dependent approach used in this study and included three species namely Limosilactobacillus reuteri (previously known as Lactobacillus reuteri), Lacticaseibacillus rhamnosus (previously known as Lactobacillus rhamnosus) and Ligilactobacillus agilis (previously known as Lactobacillus agilis). Enterococcus faecalis and E. faecium were detected where E. faecalis was the highest dominant, representing 62.5% of total LAB colonizing newborn babies. This result suggests that this bacterium has high potency for colonization and might be important for controlling the initial settlement of microbiota in healthy newborn babies. Only one species of Streptococcus namely Streptococcus agalactiae was detected in 8.33% total of the investigated newborn babies indicating high competency by other LAB for colonization and that this bacteria, in spite of its pathogenicity, is commensal in its low existence in healthy babies. The explored potency of natural initial colonization of the LAB species E. faecalis, E. faecium, L. reuteri, L. rhamnosus, and L. agilis of which many health beneficial strains were previously reported, would be important for future applications. Despite the controversy in evaluating its health benefits, E. faecalis as a potent competitor to other LAB refers to its importance in initial colonization of healthy babies colon at first week of their life. Further future studies, with more number of samples and characterization, would be of importance for evaluating the potential use of beneficial Enterococcus strains which could improve intestinal ecosystem.

Critical Appraisal of Oral Pre- and Probiotics for Caries Prevention and Care

In recent years, the concept of preventing caries-related microbial dysbiosis by enhancing the growth and survival of health-associated oral microbiota has emerged. In this article, the current evidence for the role of oral pre- and probiotics in caries prevention and caries management is discussed. Prebiotics are defined as "substrates that are selectively utilized by host microorganisms conferring a health benefit." With regard to caries, this would include alkali-generating substances such as urea and arginine, which are metabolized by some oral bacteria, resulting in ammonia production and increase in pH. While there is no evidence that urea added to chewing gums or mouth rinses significantly contributes to caries inhibition, multiple studies have shown that arginine in consumer products can exert an inhibitory effect on the caries process. Probiotics are "live microorganisms which when administrated in adequate amounts confer a health benefit on the host." Clinical trials have suggested that school-based programs with milk supplemented with probiotics and probiotic lozenges can reduce caries development in preschool children and in schoolchildren with high caries risk. Due to issues with research ethics (prebiotics) and risk of bias (prebiotics, probiotics), the confidence in the effect estimate is however limited. Further long-term clinical studies are needed with orally derived probiotic candidates, including the health-economic perspectives. In particular, the development and evaluation of oral synbiotic products, containing both prebiotics and a probiotic, would be of interest in the future management of dental caries.

Role of Lactobacillus reuteri in Human Health and Diseases

Lactobacillus reuteri (L. reuteri) is a well-studied probiotic bacterium that can colonize a large number of mammals. In humans, L. reuteri is found in different body sites, including the gastrointestinal tract, urinary tract, skin, and breast milk. The abundance of L. reuteri varies among different individuals. Several beneficial effects of L. reuteri have been noted. First, L. reuteri can produce antimicrobial molecules, such as organic acids, ethanol, and reuterin. Due to its antimicrobial activity, L. reuteri is able to inhibit the colonization of pathogenic microbes and remodel the commensal microbiota composition in the host. Second, L. reuteri can benefit the host immune system. For instance, some L. reuteri strains can reduce the production of pro-inflammatory cytokines while promoting regulatory T cell development and function. Third, bearing the ability to strengthen the intestinal barrier, the colonization of L. reuteri may decrease the microbial translocation from the gut lumen to the tissues. Microbial translocation across the intestinal epithelium has been hypothesized as an initiator of inflammation. Therefore, inflammatory diseases, including those located in the gut as well as in remote tissues, may be ameliorated by increasing the colonization of L. reuteri. Notably, the decrease in the abundance of L. reuteri in humans in the past decades is correlated with an increase in the incidences of inflammatory diseases over the same period of time. Direct supplementation or prebiotic modulation of L. reuteri may be an attractive preventive and/or therapeutic avenue against inflammatory diseases.

Demineralization-remineralization dynamics in teeth and bone

Biomineralization is a dynamic, complex, lifelong process by which living organisms control precipitations of inorganic nanocrystals within organic matrices to form unique hybrid biological tissues, for example, enamel, dentin, cementum, and bone. Understanding the process of mineral deposition is important for the development of treatments for mineralization-related diseases and also for the innovation and development of scaffolds. This review provides a thorough overview of the up-to-date information on the theories describing the possible mechanisms and the factors implicated as agonists and antagonists of mineralization. Then, the role of calcium and phosphate ions in the maintenance of teeth and bone health is described. Throughout the life, teeth and bone are at risk of demineralization, with particular emphasis on teeth, due to their anatomical arrangement and location. Teeth are exposed to food, drink, and the microbiota of the mouth; therefore, they have developed a high resistance to localized demineralization that is unmatched by bone. The mechanisms by which demineralization-remineralization process occurs in both teeth and bone and the new therapies/technologies that reverse demineralization or boost remineralization are also scrupulously discussed. Technologies discussed include composites with nano- and micron-sized inorganic minerals that can mimic mechanical properties of the tooth and bone in addition to promoting more natural repair of surrounding tissues. Turning these new technologies to products and practices would improve health care worldwide.

Bifidobacteria inhibit the growth of Porphyromonas gingivalis but not of Streptococcus mutans in an in vitro biofilm model

There is growing interest in the use of probiotic bifidobacteria for enhancement of the therapy, and in the prevention, of oral microbial diseases. However, the results of clinical studies assessing the effects of bifidobacteria on the oral microbiota are controversial, and the mechanisms of actions of probiotics in the oral cavity remain largely unknown. In addition, very little is known about the role of commensal bifidobacteria in oral health. Our aim was to study the integration of the probiotic Bifidobacterium animalis subsp. lactis Bb12 and of oral Bifidobacterium dentium and Bifidobacterium longum isolates in supragingival and subgingival biofilm models and their effects on other bacteria in biofilms in vitro using two different in vitro biofilms and agar-overlay assays. All bifidobacteria integrated well into the subgingival biofilms composed of Porphyromonas gingivalis, Actinomyces naeslundii, and Fusobacterium nucleatum and decreased significantly only the number of P. gingivalis in the biofilms. The integration of bifidobacteria into the supragingival biofilms containing Streptococcus mutans and A. naeslundii was less efficient, and bifidobacteria did not affect the number of S. mutans in biofilms. Therefore, our results suggest that bifidobacteria may have a positive effect on subgingival biofilm and thereby potential in enhancing gingival health; however, their effect on supragingival biofilm may be limited.

Effect of probiotic chewing tablets on early childhood caries--a randomized controlled trial

Background

To evaluate the effect of probiotic chewing tablets on early childhood caries development in preschool children living in a low socioeconomic multicultural area.

Methods

The investigation employed a randomized double-blind placebo-controlled design. The study group consisted of 138 healthy 2-3-year-old children that were consecutively recruited after informed parental consent. After enrollment, they were randomized to a test or a placebo group. The parents of the test group were instructed to give their child one chewing tablet per day containing three strains of live probiotic bacteria (ProBiora3®) and the placebo group got identical tablets without bacteria. The duration was one year and the prevalence and increment of initial and manifest caries lesions was examined at baseline and follow-up. All parents were thoroughly instructed to brush the teeth of their off-springs twice daily with fluoride toothpaste.

Results

The groups were balanced at baseline and the attrition rate was 20 %. Around 2/3 of the children in both groups reported an acceptable compliance. The caries increment (Δds) was significantly lower in the test group when compared with the placebo group, 0.2 vs. 0.8 (p < 0.05). The risk reduction was 0.47 (95 % CI 0.24–0.98) and the number needed to treat close to five. No differences were displayed between the groups concerning presence of visible plaque or bleeding-on-brushing. No side effects were reported.

Conclusions

The results suggested that early childhood caries development could be reduced through administration of these probiotic chewing tablets as adjunct to daily use of fluoride toothpaste in preschool children. Further studies on a possible dose–response relationship seem justified

Trial registration

ClinicalTrials.gov Identifier: NCT01720771. First received: October 31, 2012.

Electronic supplementary material

The online version of this article (doi:10.1186/s12903-015-0096-5) contains supplementary material, which is available to authorized users.

Oral Microbiota Shift after 12-Week Supplementation with Lactobacillus reuteri DSM 17938 and PTA 5289; A Randomized Control Trial

Background

Lactobacillus spp. potentially contribute to health by modulating bacterial biofilm formation, but their effects on the overall oral microbiota remain unclear.

Methods and Findings

Oral microbiota was characterized via 454-pyrosequencing of the 16S rDNA hypervariable region V3-V4 after 12 weeks of daily Lactobacillus reuteri DSM 17938 and PTA 5289 consumption. Forty-four adults were assigned to a test group (n = 22) that received lactobacilli lozenges (10⁸ CFU of each strain/lozenge) or a control group that received placebo (n = 22). Presence of L. reuteri was confirmed by cultivation and species specific PCR. Tooth biofilm samples from 16 adults before, during, and after exposure were analyzed by pyrosequencing. A total of 1,310,292 sequences were quality filtered. After removing single reads, 257 species or phylotypes were identified at 98.5% identity in the Human Oral Microbiome Database. Firmicutes, Bacteroidetes, Fusobacteria, Proteobacteria, and Actinobacteria were the most abundant phyla. Streptococcus was the most common genus and the S. oralis/S. mitis/S. mitis bv2/S. infantis group comprised the dominant species. The number of observed species was unaffected by L. reuteri exposure. However, subjects who had consumed L. reuteri were clustered in a principal coordinates analysis relative to scattering at baseline, and multivariate modeling of pyrosequencing microbiota, and culture and PCR detected L. reuteri separated baseline from 12-week samples in test subjects. L. reuteri intake correlated with increased S. oralis/S. mitis/S. mitis bv2/S. infantis group and Campylobacter concisus, Granulicatella adiacens, Bergeyella sp. HOT322, Neisseria subflava, and SR1 [G-1] sp. HOT874 detection and reduced S. mutans, S. anginosus, N. mucosa, Fusobacterium periodicum, F. nucleatum ss vincentii, and Prevotella maculosa detection. This effect had disappeared 1 month after exposure was terminated.

Conclusions

L. reuteri consumption did not affect species richness but induced a shift in the oral microbiota composition. The biological relevance of this remains to be elucidated.

Trial Registration

ClinicalTrials.gov NCT02311218

Effect of Probiotic Containing Ice-cream on Salivary Mutans Streptococci (SMS) Levels in Children of 6-12 Years of Age: A Randomized Controlled Double Blind Study with Six-months Follow Up

INTRODUCTION

To evaluate the caries risk based on the salivary levels of streptococcus mutans in children of 6-12 years of age group before and after consuming probiotic ice-cream containing Bifidobacterium lactis Bb-12 and Lactobacillus acidophilus La-5.

MATERIALS AND METHODS

A double blind, placebo controlled trial was carried out in 60 children aged between 6 to 12 years with zero decayed, missing, and filled teeth (DMFT). They were randomly divided into two equal groups. Saliva sample were collected before the consumption of ice-cream and Streptococcus mutans count was calculated and recorded as baseline data. For the next seven days both the groups were given ice creams marked as A and B. Saliva samples were collected after ice-cream consumption at the end of study period and also after a washout period of 30 days and again after six months. Samples were inoculated and colonies were counted.

RESULTS

On statistical evaluation by students paired t-test, probiotic ice-cream brought significant reduction in the Streptococcus mutans count after seven days of ice-cream ingestion (p<0.001) and also after 30 d of washout period (p<0.001). There was no significant reduction (p=0.076) by normal ice-cream consumption. After six months of the study period in both the groups the salivary levels of Streptococcus mutans was similar to the baseline.

CONCLUSION

Probiotic ice-cream containing Bifidobacterium lactis Bb-12 and Lactobacillus acidophilus La-5 can cause reduction in caries causative organism. The dosage of the probiotic organisms for the long term or synergetic effect on the oral health are still needed to be explored.