Effect of Probiotic Curd on Salivary pH and Streptococcus mutans: A Double Blind Parallel Randomized Controlled Trial

Modulation of the Human Microbiome: Probiotics, Prebiotics, and Microbial Transplants

The balance between health and disease is intrinsically linked to the interactions between microbial communities and the host. This complex environment of antagonism and synergy involves both prokaryotic and eukaryotic cells, whose collaborative metabolic pathways and immunomodulatory elements influence system homeostasis. As with the gut and other niches, the oral microbiome has the capacity to affect distal host sites. The ability to manipulate this environment holds the potential to impact local and systemic disease.With the increasing threat of antimicrobial resistance, novel approaches to reduce the burden of disease are essential. The use of probiotics and prebiotics is one such strategy. Probiotics introduce non-pathogenic bacteria into the environment to compete with pathogens for nutrients and attachment sites, or to produce metabolites that counteract disease aetiologies. Prebiotic compounds enhance the growth of health-associated organisms, offering additional benefits, whilst a conjunctive approach with probiotics potentially holds even greater promise. Though widely studied in the gastrointestinal context, their potential for treating oral diseases, such as dental caries and periodontitis, is less understood. Additionally, the use of microbial transplantations has demonstrated efficacy in other areas, reducing systemic inflammation and recolonising with commensal bacteria. Here we evaluate their use in the oral context and their modulatory impact on overall health.In this chapter, we discuss how pro- and prebiotic strategies seek to modulate both the oral and gut environments to promote oral health and prevent disease. We assess novel approaches for utilising health-associated microorganisms to combat oral disorders, either administered locally in the mouth or imparting influence through immune modulation via the oral-gut axis. By examining available clinical trial data, we aim to further understand the intricacies involved in this discipline. Furthermore, we consider the challenges facing the research community, including optimal candidate organism/compound selection and colonisation retention, as well as considerations for future research.

The oral microbial odyssey influencing chronic metabolic disease

INTRODUCTION

Since the oral cavity is the gateway to the gut, oral microbes likely hold the potential to influence metabolic disease by affecting the gut microbiota.

METHOD

A thorough review of literature has been performed to link the alterations in oral microbiota with chronic metabolic disease by influencing the gut microbiota.

RESULT

A strong correlation exists between abnormalities in oral microbiota and several systemic disorders, such as cardiovascular disease, diabetes, and obesity, which likely initially manifest as oral diseases. Ensuring adequate oral hygiene practices and cultivating diverse oral microflora are crucial for the preservation of general well-being. Oral bacteria have the ability to establish and endure in the gastrointestinal tract, leading to the development of prolonged inflammation and activation of the immune system. Oral microbe-associated prophylactic strategies could be beneficial in mitigating metabolic diseases.

CONCLUSION

Oral microbiota can have a profound impact on the gut microbiota and influence the pathogenesis of metabolic diseases.

The role of Lactobacillus plantarum in oral health: a review of current studies

Background

Oral non-communicable diseases, particularly dental caries and periodontal disease, impose a significant global health burden. The underlying microbial dysbiosis is a prominent factor, driving interest in strategies that promote a balanced oral microbiome. Lactobacillus plantarum, a gram-positive lactic acid bacterium known for its adaptability, has gained attention for its potential to enhance oral health. Recent studies have explored the use of probiotic L. plantarum in managing dental caries, periodontal disease, and apical periodontitis. However, a comprehensive review on its effects in this context is still lacking.

Aims

This narrative review evaluates current literature on L. plantarum's role in promoting oral health and highlights areas for future research.

Content

In general, the utilization of L. plantarum in managing non-communicable biofilm-dependent oral diseases is promising, but additional investigations are warranted. Key areas for future study include: exploring its mechanisms of action, identifying optimal strains or strain combinations of L. plantarum, determining effective delivery methods and dosages, developing commercial antibacterial agents from L. plantarum, and addressing safety considerations related to its use in oral care.

How probiotics, prebiotics, synbiotics, and postbiotics prevent dental caries: an oral microbiota perspective

Dental caries, a highly prevalent oral disease, impacts a significant portion of the global population. Conventional approaches that indiscriminately eradicate microbes disrupt the natural equilibrium of the oral microbiota. In contrast, biointervention strategies aim to restore this balance by introducing beneficial microorganisms or inhibiting cariogenic ones. Over the past three decades, microbial preparations have garnered considerable attention in dental research for the prevention and treatment of dental caries. However, unlike related pathologies in the gastrointestinal, vaginal, and respiratory tracts, dental caries occurs on hard tissues such as tooth enamel and is closely associated with localized acid overproduction facilitated by cariogenic biofilms. Therefore, it is insufficient to rely solely on previous mechanisms to delineate the role of microbial preparations in the oral cavity. A more comprehensive perspective should involve considering the concepts of cariogenic biofilms. This review elucidates the latest research progress, mechanisms of action, challenges, and future research directions regarding probiotics, prebiotics, synbiotics, and postbiotics for the prevention and treatment of dental caries, taking into account the unique pathogenic mechanisms of dental caries. With an enhanced understanding of oral microbiota, personalized microbial therapy will emerge as a critical future research trend.

Manipulating the diseased oral microbiome: the power of probiotics and prebiotics

Dental caries and periodontal disease are amongst the most prevalent global disorders. Their aetiology is rooted in microbial activity within the oral cavity, through the generation of detrimental metabolites and the instigation of potentially adverse host immune responses. Due to the increasing threat of antimicrobial resistance, alternative approaches to readdress the balance are necessary. Advances in sequencing technologies have established relationships between disease and oral dysbiosis, and commercial enterprises seek to identify probiotic and prebiotic formulations to tackle preventable oral disorders through colonisation with, or promotion of, beneficial microbes. It is the metabolic characteristics and immunomodulatory capabilities of resident species which underlie health status. Research emphasis on the metabolic environment of the oral cavity has elucidated relationships between commensal and pathogenic organisms, for example, the sequential metabolism of fermentable carbohydrates deemed central to acid production in cariogenicity. Therefore, a focus on the preservation of an ecological homeostasis in the oral environment may be the most appropriate approach to health conservation. In this review we discuss an ecological approach to the maintenance of a healthy oral environment and debate the potential use of probiotic and prebiotic supplementation, specifically targeted at sustaining oral niches to preserve the delicately balanced microbiome.

Erosive tooth wear and salivary parameters among competitive swimmers and non-swimmers in Egypt: a cross-sectional study

INTRODUCTION

Competitive swimmers spend considerable time practicing their sport. Prolonged exposure to chlorinated water can alter salivary parameters and might compromise oral health. This study aimed to determine erosive tooth wear status and its related risk factors among competitive swimmers as compared to non-swimmers.

MATERIALS AND METHODS

A cross-sectional study consisting of 180 athletes (90 competitive swimmers versus 90 competitive rowers "non-swimmers") was conducted. Participants were interviewed on the common erosion risk factors. The Basic Erosive Wear Examination system was used to assess the status of erosive tooth wear. Stimulated saliva sample was collected before and after a training session and pool pH was evaluated using pH strips for 7 days. Data were analyzed using descriptive statistics and multivariable analysis.

RESULTS

The prevalence of dental erosion was significantly higher among competitive swimmers (60%) with higher BEWE scores compared to non-swimmers (25.6%). The salivary flow rate was reduced significantly after training sessions in both groups while salivary pH increased among swimmers. Evaluation of pool water revealed a continuous reduction in the pH level, reaching a very acidic pH level of 3.24.

CONCLUSION

Erosive tooth wear is more prevalent among competitive swimmers. Years of practice and regular consumption of acidic drinks increase the odds of developing erosive lesions. A high incidence of erosive lesions may be attributed to a reduction in swimming pool pH level. Salivary parameters showed variations between groups after training sessions.

Association of polymicrobial interactions with dental caries development and prevention

Dental caries is a common oral disease. In many cases, disruption of the ecological balance of the oral cavity can result in the occurrence of dental caries. There are many cariogenic microbiota and factors, and their identification allows us to take corresponding prevention and control measures. With the development of microbiology, the caries-causing bacteria have evolved from the traditional single Streptococcus mutans to the discovery of oral symbiotic bacteria. Thus it is necessary to systematically organized the association of polymicrobial interactions with dental caries development. In terms of ecology, caries occurs due to an ecological imbalance of the microbiota, caused by the growth and reproduction of cariogenic microbiota due to external factors or the disruption of homeostasis by one's own factors. To reduce the occurrence of dental caries effectively, and considering the latest scientific viewpoints, caries may be viewed from the perspective of ecology, and preventive measures can be taken; hence, this article systematically summarizes the prevention and treatment of dental caries from the aspects of ecological perspectives, in particular the ecological biofilm formation, bacterial quorum sensing, the main cariogenic microbiota, and preventive measures.

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.

Lactobacillus acidophilus novel strain, MJCD175, as a potential probiotic for oral health in dogs

The oral cavity is the second-largest habitat for microorganisms, and a well-balanced oral microbiome contributes to preventing dental disorders caused by pathogenic bacteria. Since humans and dogs have different lifestyles and oral microbiome structures, the present study aimed to develop novel probiotics for dogs. A total 53 Lactobacillus spp. were isolated from healthy dogs, and nine isolates were identified as Lactobacillus acidophilus according to 16S rRNA gene sequencing. According to the high antimicrobial activity against the dental caries-causing bacterium Streptococcus mutans, single or three mixed strains were orally administered to dogs for 4 weeks with concentration of 10⁸-10⁹ CFU/day. Intraoral swab samples were collected before and after the administration, and changes of oral pathogen were analyzed using quantitative PCR. Among them, Porphyromonas gingivalis, a critical factor of periodontitis, was significantly reduced in the single-strain administered group. Based on the acid and bile salts tolerance characteristics of isolates, systemic effects were also analyzed by comparing serum immunoglobulin and reproductive ability before and after the administration. However, no significant changes were observed in the serum IgG level and sperm quality. Overall, these in vitro and in vivo results suggest that L. acidophilus isolates from dogs, especially L. acidophilus MJCD175, could be promising probiotic candidates to support oral health without systemic adverse effects in dogs.

Evaluation of the Effect of Probiotic Yogurt Consumption on Salivary pH, Buffering Capacity and Calcium Level in 6-12-year-old Children: An In Vivo Study

Introduction

Dental caries is a preventable disease that can be prevented by suppressing any one of the factors of the Keyes triad.

Aim and objective

To investigate the effect of probiotic yogurt on salivary pH, calcium level, and buffering capacity.

Materials and methods

A total of 60 children were randomly selected and were divided into 2 groups. The test group consumed 200 mL of probiotic yogurt and the control group consumed 200 mL of regular curd everyday for 30 days. A base-line nonstimulated salivary sample (2 mL) was collected. The salivary pH, buffering capacity, and calcium level was assessed at baseline, after 15 and 30 days. The data were statistically analyzed.

Result

The mean pH levels of the probiotic group were 7.03 and salivary buffering capacity was found to be 2.000. Salivary calcium levels increased with the use of probiotic yogurt at the end of 30 days (mean of 4.79) compared to the control group.

Conclusion

Consumption of probiotic yogurt for a short period of time can prevent dental caries by increasing salivary calcium level.

How to cite this article

Malavalli PL, Shetty SB, Thimmaiah C, et al. Evaluation of the Effect of Probiotic Yogurt Consumption on Salivary pH, Buffering Capacity and Calcium Level in 6-12-year-old Children: An In Vivo Study. Int J Clin Pediatr Dent 2022;15(2):194-198.

Assessing the drug resistance profiles of oral probiotic lozenges

Background

Probiotic lozenges have been developed to harvest the benefits of probiotics for oral health, but their long-term consumption may encourage the transfer of resistance genes from probiotics to commensals, and eventually to disease-causing bacteria.

Aim

To screen commercial probiotic lozenges for resistance to antibiotics, characterize the resistance determinants, and examine their transferability in vitro.

Results

Probiotics of all lozenges were resistant to glycopeptide, sulfonamide, and penicillin antibiotics, while some were resistant to aminoglycosides and cephalosporins. High minimum inhibitory concentrations (MICs) were detected for streptomycin (>128 µg/mL) and chloramphenicol (> 512 µg/mL) for all probiotics but only one was resistant to piperacillin (MIC = 32 µg/mL). PCR analysis detected erythromycin (erm(T), ermB or mefA) and fluoroquinolone (parC or gyr(A)) resistance genes in some lozenges although there were no resistant phenotypes. The dfrD, cat-TC, vatE, aadE, vanX, and aph(3")-III or ant(2")-I genes conferring resistance to trimethoprim, chloramphenicol, quinupristin/dalfopristin, vancomycin, and streptomycin, respectively, were detected in resistant probiotics. The rifampicin resistance gene rpoB was also present. We found no conjugal transfer of streptomycin resistance genes in our co-incubation experiments.

Conclusion

Our study represents the first antibiotic resistance profiling of probiotics from oral lozenges, thus highlighting the health risk especially in the prevailing threat of drug resistance globally.

Comparison of Antibacterial Effect of Probiotic Yogurt and Xylitol-Containing Chewing Gum in Geriatric Patients: A Randomized Controlled Clinical Trial

Objectives

To evaluate the effect of probiotic bacteria in yogurt on Streptococcus mutans (MS) count, plaque adherence and salivary pH compared to xylitol-containing chewing gum in geriatric patients.

Materials and methods

Total number of 96 high caries risk geriatric patients were randomized into two equal groups (n=48). Group 1 (intervention group) received probiotic yogurt (Activia, Danone) once per day, and group 2 (control group) received xylitol chewing gum (Trident original) three times per day. The primary outcome was salivary Streptococcus mutans count and secondary outcomes were interdental plaque Streptococcus mutans count, salivary pH and bacterial adherence.

Results

For Streptococcus mutans count in saliva and plaque, a statistically significant reduction in the level of MS over all the examined follow up periods of the study in probiotic yogurt group as well as xylitol gum group was found. An intergroup comparison for salivary MS count showed statistically significant difference between the two materials in a two week and a three month period of time and there was no statistically significant difference between both materials at one month time period. Salivary pH results showed statistically significant increase in pH in both groups along the follow-up periods. Bacterial adherence results showed statistically significant reduction in both groups.

Conclusions

Probiotic yogurt is an effective antibacterial agent against salivary and plaque bacteria in geriatric patients.

Effectiveness of probiotic lozenges and Chlorhexidine mouthwash on plaque index, salivary pH, and Streptococcus mutans count among school children in Makkah, Saudi Arabia

Purpose

To compare the effect of the probiotic lozenges and chlorhexidine (CHX) mouthwash on plaque index (PI) , salivary pH and Streptococcus mutans (S. mutans) 3 count among groups of Saudi children.

Methods

A total of 54 participants aged 8-12 years were randomly allocated into three groups, 18 children in each group. Children in the probiotic group consumed one probiotic lozenge (Biogaia prodentis) daily, while children in the CHX group were instructed to use CHX mouthwash twice daily. The control group was only instructed to follow regular oral hygiene measures. Saliva samples were taken at baseline, 15th and 30th days. PI scores, salivary pH values and S. mutans count were evaluated. Data were statistically analyzed using the ANOVA and the Tukey post-hoc test.

Results

Probiotic lozenges and CHX mouthwash significantly reduced PI and S. mutans count and increased the salivary pH values. However, there were no statistical differences between the effect of probiotic lozenges and CHX mouthwash on PI (p-value= 800) and pH values (p-value= 0.927) on the 30th day. Conversely a significant difference was reported among their effects on S. mutans count (p-value=0.014) on the 30th day. Greater acceptance and compliance of children to probiotic lozenges were reported.

Conclusions

Probiotic lozenges could be an alternative to CHX mouthwash and encouraged to be included with the daily oral hygiene measures.

Comparative Evaluation of Efficacy of Kefir Milk Probiotic Curd and Probiotic Drink on Streptococcus mutans in 8-12-year-old Children: An In Vivo Study

AIM AND OBJECTIVE

To compare the effect of probiotic products in reducing the levels of salivary Streptococcus mutans before and after their consumption.

MATERIALS AND METHODS

Eighty school children with initial carious lesions in the age group of 8-12 years were selected and divided into four groups. Children in group I (control) were undergone with restorations without supplementation of probiotics. Children in group II (kefir milk), group III (probiotic curd), and group IV (probiotic drink) supplemented 100 mL of their respective probiotics for 1 month. Assessment of saliva sample was done at baseline, 1 hour after administration of probiotics followed by weekly intervals till 1 month.

RESULTS

The study showed a marked reduction in colony-forming units (CFUs) at a 1-hour time interval in all four groups when compared to baseline. On the 30th-day, children in group II and group III have shown an equal reduction of CFUs when compared to group IV and group I.

CONCLUSION

Probiotic products like kefir milk and probiotic curd have shown an equal and marked decrease in CFUs when compared to the probiotic drink group.

CLINICAL SIGNIFICANCE

The administration of probiotics along with dairy products can be used as an adjuvant to routine preventive treatment procedures in the prevention of dental caries along with the remineralization of the demineralized tooth structure.

HOW TO CITE THIS ARTICLE

Reddy S, Madhu V, Punithavathy R, et al. Comparative Evaluation of Efficacy of Kefir Milk Probiotic Curd and Probiotic Drink on Streptococcus mutans in 8-12-year-old Children: An In Vivo Study. Int J Clin Pediatr Dent 2021;14(1):120-127.

A Comparative Study to Evaluate the Effects of Probiotic Curd on Streptococcus mutans, Bifidobacterium dentium, and pH of Saliva in Caries-free Children: An In Vivo Study

BACKGROUND

Dental caries is one of the commonest oral diseases that require early stages of prevention and intervention. The primary organisms related to dental caries are streptococcus mutans and lactobacilli. In the past decades, some of the non-pathogenic bacteria called probiotics have been added to the food products for the beneficial effect of human health. Intake of probiotic food products has been shown to have beneficial effects on the oral tissues. Hence the present study aimed to compare the levels of salivary pH, S. mutans, B. dentium counts in children consuming probiotic and non-probiotic curd.

METHODS AND MATERIAL

40 healthy caries free children were randomly allocated into two groups. First baseline salivary samples were collected from all the participants and tested for salivary pH, salivary B. dentium and S. mutans count. After collecting the baseline values test group of children were provided with probiotic curd whereas the control group were provided with non probiotic curd for 15 days. After 15 days of consumption of these dairy products, salivary samples were collected again and tested for salivary pH, salivary B. dentium and S. mutans count.

RESULTS

Probiotic curd was found to be more effective in reducing the colony counts of B.dentium and S.mutans. There was a marginal decrease in pH in both the groups but was well above the critical pH.

CONCLUSIONS

Probiotic curd showed considerable level of decrease in colony counts of B.dentium, S.mutans and salivary pH when compared to normal curd.

Are dairy products containing probiotics beneficial for oral health? A systematic review and meta-analysis

OBJECTIVES

To evaluate the effect of probiotic containing in dairy products on oral and salivary parameters.

MATERIAL AND METHODS

Electronic searches were performed based on the PICO criteria. Randomized controlled trials in adults/children (P) in which dairy products containing probiotics (I) were compared to controls (C) for establishment of oral health (O) were included. Risk of bias and data extraction were performed. The meta-analysis evaluated the influence of probiotics on Streptococcus mutans (SM), Lactobacillus spp. (LB), and yeast counts, plaque index, and salivary pH. Random or fixed effect models were used, and heterogeneity was tested.

RESULTS

Thirty-two studies were included in the qualitative synthesis, and 24 in the meta-analysis. For dichotomous results, individuals who consumed probiotics exhibited decreased scores in SM concentrations (RD 0.15 [0.02, 0.28] p = 0.03, I² = 70%), but no change was observed for LB (RD 0.10 [- 0.03, 0.23] p = 0.13, I² = 94%), or yeast levels (RD 0.05 [- 0.02, 0.12] p = 0.7, I² = 48%). For continuous analysis, both probiotic and control groups presented similar results for SM and LB (MD - 0.55 [- 1.16, 0.07] p = 0.08, I² = 62%, and RD 0.10 [- 0.03, 0.23] p = 0.13, I² = 94%, respectively). The consumption of probiotics increased salivary pH (MD 0.20 [0.04, 0.35] p = 0.01, I² = 46%) and plaque index (MD 0.38 [0.11, 0.65] p = 0.005, I² = 0%). The probiotic milk reduced SM (MD - 0.59 [- 0.96, - 0.22] p = 0.002, I² = 0%), and the probiotic yogurt decreased LB counts (RD 0.35 [0.19, 0.51] p < 0.0001, I² = 0%).

CONCLUSIONS

In general, dairy probiotics were effective in reducing SM, increasing salivary pH, and promoting a higher plaque index. Liquid matrices, such as milk and yogurt, seem to be more effective in reducing SM and LB levels.

CLINICAL RELEVANCE

Consumption of dairy products containing probiotics could be a supporting method in caries prevention.

Efficacy of probiotics: clinical and microbial parameters of halitosis

BACKGROUND & AIM

Halitosis is defined as an offensive breath odour of whatever source and therefore may affect a person's social interactions. Intra-oral halitosis is a result of bacterial activity. Therefore, probiotics may offer an appropriate and biological solution as a part of the therapy of intra-oral halitosis. The aim of this systematic review was to study the effect of the administration of probiotics alone or as an adjunct to other treatments on the level of halitosis as measured by volatile sulphur compound (VSC) levels, organoleptic scores (ORG) or hydrogen sulphide, methyl mercaptan and dimethyl sulphide levels. In addition, the effect of probiotic usage on oral microbial composition was summarised.

METHODS

The MEDLINE-PubMed and Embase databases were searched up to September 2017 with language restricted to English. Eligible papers were selected according to pre-set criteria; the data was extracted and analysed descriptively.

RESULTS

The search resulted in 1104 original research articles and a final six were selected as being eligible including 129 subjects. These studies used different detection methods and combinations thereof to measure halitosis. Five studies were randomised placebo-controlled clinical trials of which two studies reported a significant reduction in ORG between probiotic and placebo groups, and two studies on the basis of total VSC levels. The two studies reporting a significant improvement in ORG did not find an improvement in total VSC levels. Three studies included a microbiological assessment. In these three studies, the probiotic strain was detected at the end of the treatment period, but no detailed data was reported on the abundance of the strain before and after the treatment period.

CONCLUSIONS

Probiotics may be beneficial in treating intra-oral halitosis. However, due to limited data and the heterogeneity of the studies, the efficacy of probiotics remains unclear. Studies with more subjects and standardised protocols need to be designed.

Ecological Therapeutic Opportunities for Oral Diseases

The three main oral diseases of humans, that is, caries, periodontal diseases, and oral candidiasis, are associated with microbiome shifts initiated by changes in the oral environment and/or decreased effectiveness of mucosal immune surveillance. In this review, we discuss the role that microbial-based therapies may have in the control of these conditions. Most investigations on the use of microorganisms for management of oral disease have been conducted with probiotic strains with some positive but very discrete clinical outcomes. Other strategies such as whole oral microbiome transplantation or modification of community function by enrichment with health-promoting indigenous oral strains may offer more promise, but research in this field is still in its infancy. Any microbial-based therapeutics for oral conditions, however, are likely to be only one component within a holistic preventive strategy that should also aim at modification of the environmental influences responsible for the initiation and perpetuation of microbiome shifts associated with oral dysbiosis.

Effect of Short-term Consumption of Amul Probiotic Yogurt Containing Lactobacillus acidophilus La5 and Bifidobacterium Lactis Bb12 on Salivary Streptococcus mutans Count in High Caries Risk Individuals

Aim

This study aims to study the effect of short-term consumption of probiotic yogurt containing Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 on salivary Streptococcus mutans count in high caries risk individuals.

Materials and Methods

A double-blind randomized control trial was conducted, and 70 high caries risk individuals with a salivary S. mutans count of more than 10⁶ CFU/ml of saliva were followed for 4 weeks. Participants ingested 100 g yogurt containing L. acidophilus La5 and Bifidobacterium lactis Bb12 or yogurt without the two probiotic bacteria once daily at the end of meals for initial 2 weeks. Salivary S. mutans were enumerated in the laboratory by selective culture media.

Results

A statistically significant reduction (P < 0.05) of salivary S. mutans was recorded after probiotic yogurt consumption with minimal residual effect, which was in contrast to the controls.

Conclusion

L. acidophilus La5 and Bifidobacterium lactis Bb12 present in the yogurt were effective in reducing the S. mutans levels in saliva.