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

A Three-Month Probiotic (the Streptococcus salivarius M18 Strain) Supplementation Decreases Gingival Bleeding and Plaque Accumulation: A Randomized Clinical Trial

S. salivarius M18 administration has been proven to provide positive effects on periodontal health; however, there is still no consensus on the optimum duration of probiotic administration. This study aimed to evaluate the effect of three months of probiotic supplementation on bleeding on probing, signs of gingival inflammation, and dental biofilm. Sixty-two eligible individuals with gingivitis were enrolled in this placebo-controlled, double-blind trial and randomly allocated to the M18 or control groups. Primary outcomes were changes in gingival condition (gingival index, GI; gingival bleeding index, GBI) after 1, 2, and 3 months of lozenges administration and after a one-month washout. Secondary outcomes included changes in the Quigley-Hein plaque index (modified by Turesky et al.) after 1, 2, and 3 months of lozenges administration and after a washout. In total, 60 individuals completed the study (31 and 29 in the M18 group and the control group, respectively). No severe adverse events were reported. Probiotic supplementation resulted in a significant decrease in gingival bleeding at 1 month (effect size 1.09 [CI95%: 0.55-1.63]), 2 months (effect size 0.78 [CI95%: 0.26-1.30]), and 3 months (effect size 0.67 [CI95%: 0.15-1.18]) and a significant reduction in dental plaque accumulation at 2 months (effect size 0.63 [CI95%: 0.12-1.14]) and 3 months (effect size 0.55 [CI95%: 0.03-1.05]). A three-month supplementation with the probiotic resulted in a significant reduction in gingival bleeding and biofilm accumulation; however, a long-lasting effect is not expected, indicating the need for probiotic intake on a long-term basis.

Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis

We assessed the impact of probiotics on outcomes related to caries in children and/or adolescents without underlying systemic diseases. We performed a comprehensive meta-analysis of randomised controlled trials (RCTs). Searches were performed in Embase, PubMed, Scopus and Web of Science until March 2023 for RCTs assessing probiotics with a minimum intake duration of 0.2 months vs. control (no treatment or placebo) and reporting at least one primary or secondary outcome. Primary outcomes were number of carious, Streptococcus mutans count, and Lactobacillus count; secondary outcomes were bacterial plaque index, gingival index, salivary pH, and bleeding index. We performed meta-analyses with random effects models and the inverse variance method. Effects were described as mean difference (MD) with their 95% confidence intervals (95%CI). The risk of bias was assessed with the RoB 2.0 tool. The GRADE methodology was used to assess the quality of evidence (QoE). Nineteen RCTs were included (n = 2622), with a follow-up range of 0.2 to 108 months. Probiotics had no effect on reduction of dental caries (MD -0.24 carious pieces, 95%CI -0.72 to 0.23; I2 = 52%, low QoE) or Lactobacillus count (MD -0.78 CFU/mL, 95%CI -1.65 to 0.09; I2= 52%, very low QoE) vs. control. However, probiotics probably reduced S. mutans count vs. control (MD -0.40 CFU/mL, 95%CI -0.57 to -0.24; I2 = 11%, moderate QoE). Probiotics had no effect on bacterial plaque index (MD 0.21 units of bacterial plaque, 95%CI -0. 55-0.96; I2 = 80%, very low QoE), gingival index (MD 0.04 units of gingival index, 95%CI -0.18 to 0.27; I2= 0%, low QoE), and salivary pH (MD -0.12 pH units, 95%CI -0.72 to 0.48; I2 = 92%, very low QoE) vs. control. Probiotics were found to likely reduce S. mutans counts. However, no significant effect of probiotics was observed in reducing other outcomes compared to the control group.

Probiotics-containing beverages and dental caries: A systematic review and meta-analysis

The aim was to evaluate the effect of probiotics-containing beverages on dental caries development by a systematic review and meta-analysis (PROSPERO CRD42021258010). PubMed, Embase, and Web of Science databases were assessed (up to October 2023) for randomized placebo-controlled trials that evaluated the consumption of probiotics-containing beverages having dental caries as endpoint. Risk of bias assessment (Cochrane Handbook) was performed for all studies. Risk ratio (RR), standardized mean difference (SMD) and 95% confidence interval (CI), were calculated for caries prevalence and caries increment, respectively. Meta-analysis was performed. Qualitative analysis of more than 2000 individuals aged from 1 to 84 years (9 studies) showed inconsistent effects of these probiotics-containing beverages. Synthesis of more than 1000 children and adolescents did not demonstrate a statistically significant difference in the proportion of individuals with cavitated lesions (RR 0.60 [95 % CI 0.34 to 1.08]; n = 2), but a significantly smaller increment of both cavitated and non-cavitated carious lesions (SMD -0.23 [95 % CI -0.39 to -0.08]; n = 4) was related to the consumption of probiotics-containing beverages. Certainty of evidence for caries prevalence and caries increment were moderate and low, respectively. Current evidence is not substantial to strengthen the impact of these beverages on caries development.

A review of dairy food intake for improving health among black children and adolescents in the US

Adequate nutrition during childhood and adolescence is crucial for proper neurological, musculoskeletal, immunological, and cardiometabolic health and development. Yet, disparities among socially underserved racial/ethnic groups in the United States (US) provide significant challenges to achieving adequate nutrition during these years of rapid growth and maturation. For example, Black children and adolescents are at greater risk for having food insecurity, lower-quality diets, obesity, and numerous associated health challenges that result from these disparities compared to their White peers. A growing body of evidence indicates that improving diet quality is critical for improving childhood and adolescent health and well-being, and that the diverse nutritional profile and bioactive compounds found within dairy foods may play multiple roles in promoting proper growth and development during these life stages. Therefore, to support overall health and development among Black youth, greater education and implementation efforts are needed to help this population meet the national dietary recommendations of 2.5 to 3 servings of dairy foods per day. Continuing to fall short of these recommendations puts Black children and adolescents at risk of multiple nutrient inadequacies and health disparities that can have lifelong impacts on disease development, mental health, and quality of life. This review presents the state of knowledge on health disparities and modifiable nutritional strategies involving milk and dairy foods to support the growth and maturation of children and adolescents, with a special focus on Black youth in the US.

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.

The Anti-Inflammatory and Curative Exponent of Probiotics: A Comprehensive and Authentic Ingredient for the Sustained Functioning of Major Human Organs

Several billion microorganisms reside in the gastrointestinal lumen, including viruses, bacteria, fungi, and yeast. Among them, probiotics were primarily used to cure digestive disorders such as intestinal infections and diarrhea; however, with a paradigm shift towards alleviating health through food, their importance is large. Moreover, recent studies have changed the perspective that probiotics prevent numerous ailments in the major organs. Probiotics primarily produce biologically active compounds targeting discommodious pathogens. This review demonstrates the implications of using probiotics from different genres to prevent and alleviate ailments in the primary human organs. The findings reveal that probiotics immediately activate anti-inflammatory mechanisms by producing anti-inflammatory cytokines such as interleukin (IL)-4, IL-10, IL-11, and IL-13, and hindering pro-inflammatory cytokines such as IL-1, IL-6, and TNF-α by involving regulatory T cells (Tregs) and T helper cells (Th cells). Several strains of Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus reuteri, Bifidobacterium longum, and Bifidobacterium breve have been listed among the probiotics that are excellent in alleviating various simple to complex ailments. Therefore, the importance of probiotics necessitates robust research to unveil the implications of probiotics, including the potency of strains, the optimal dosages, the combination of probiotics, their habitat in the host, the host response, and other pertinent factors.

Unlocking the potential of probiotic administration in caries management: a systematic review

BACKGROUND

The use of prebiotics and/or probiotic bacteria with the potential to modulate the oral ecosystem may play an important role in the prevention and management of dental caries. To assess the evidence of the potential of pre/probiotics both in the prevention and treatment of dental caries, we focused on the PICO question "In individuals with caries, after probiotic administration, is there an improvement in outcomes directly related to caries risk and development?".

METHODS

An extensive systematic search was conducted in electronic databases PubMed, Web of Science, Scopus and Cochrane, to identify articles with relevant data. This systematic review included trials performed in Humans; published in English; including the observation of patients with caries, with clear indication of the probiotic used and measuring the outcomes directly involved with the cariogenic process, including the quantification of bacteria with cariogenic potential. To evaluate the methodological quality of the studies, the critical assessment tool from the Joanna Briggs Institute was used.

RESULTS

Eight hundred and fifty articles, potentially relevant, were identified. Following PRISMA guidelines 14 articles were included in this systematic review. Outcomes such as reduction of cariogenic microorganism counts, salivary pH, buffer capacity, and caries activity were assessed. The probiotic most often referred with beneficial results in dental caries outcomes is Lacticaseibacillus rhamnosus. Regarding the most used administration vehicle, in studies with positive effects on the caries management, probiotic supplemented milk could be considered the best administration vehicle.

CONCLUSIONS

Evidence suggests a beneficial effect of probiotic supplemented milk (Lacticaseibacillus rhamnosus) as an adjuvant for caries prevention and management. However, comparable evidence is scarce and better designed and comparable studies are needed.

Bifidobacterium animalis subsp. lactis as adjunct to non-surgical periodontal treatment in periodontitis: a randomized controlled clinical trial

OBJECTIVES

The purpose of this study is to investigate the clinical and microbiological effects of Bifidobacterium animalis subsp. lactis DN-173010 containing yogurt as an adjunct to non-surgical periodontal treatment in periodontitis patients.

MATERIALS AND METHODS

This is a prospective randomized controlled clinical study registered with NCT05408364 under clinical trial registration. Thirty periodontitis patients were divided into 2 groups at random. As adjunctive to supra and subgingival instrumentation, the test group consumed Bifidobacterium animalis subsp. lactis DN-173010 containing yogurt while the control group consumed natural yogurt, once daily for 28 days. The plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL) were recorded at baseline, 28th day, and 3rd month. Microbiological analysis was performed using culture method by obtaining subgingival plaque samples from 2 periodontal sites with 4≤PD≤6 mm at the same time points.

RESULTS

The inter-group comparisons of PI, GI, and BOP as well as the changes between the measurement time points were statistically significant in favor of the test group. There were no significant differences in terms of PD and CAL changes between the study groups at all times (∆baseline-28 days, ∆baseline-3 months) (p>0.05). The number of patients presenting subgingival Bifidobacterium species was significantly greater in the test group than the control group at the 28th day (p<0.05).

CONCLUSIONS

The administration of probiotics has shown beneficial effects, albeit limited, on clinical and microbiological outcomes in the management of periodontitis patients.

CLINICAL RELEVANCE

Daily consumption of probiotic yogurt may be supportive for supra and subgingival instrumentation.

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.

Effect of synbiotic mouthwash on oral mucositis induced by radiotherapy in oral cancer patients: a double-blind randomized clinical trial

PURPOSE

Considering the complex pathobiology of oral mucositis, especially in oral cancer patients, the prevention and treatment of oral mucositis in patients undergoing radiotherapy remains an essential and clinically crucial unmet need. The present study aims to investigate and compare the effects of synbiotic mouthwash with normal saline mouthwash on the prevention and control of radiotherapy-induced oral mucositis in oral cancer patients.

METHODS

Double-blind, randomized clinical trial (RCT) performed on 64 oral cancer patients who underwent radiotherapy (IRCT20201106049288N1, registration date: 2020-12-23). Patients were divided randomly into the case (32 subjects) and control (32 subjects) groups. All patients underwent intensity-modulated radiotherapy and received 6000 cGY of radiotherapy in 34 fractions. All patients received the usual treatment for mucositis, but in the case group, synbiotic mouthwash was prescribed and in the control group, normal saline mouthwash was prescribed from a day before the start to the end of radiotherapy treatment. Patients were monitored every session for 6 weeks to check the progression, oral involvement severity, and mucositis grade.

RESULTS

The case group showed a significant reduction in the oral mucositis severity. The mucositis grade in the case group from the 7th session of oral examination was significantly lower than the control (p < 0.05), and this significant difference persisted until the last session of oral examination. Incidence rates of severe oral mucositis (grade 3) during the treatment period were 11.59% in the case and 36.45% in control (p < 0.001).

CONCLUSION

Synbiotic mouthwash significantly reduces and prevents oral mucositis intensity in oral cancer patients undergoing radiotherapy.

Malnutrition, nutrition support and dietary intervention: the role of the dietitian supporting patients with head and neck cancer

Malnutrition is prevalent in patients with head and neck cancer (HNC) at diagnosis but can occur at any stage of the treatment pathway. The impact of disease burden and treatment side effects can lead to altered anatomy, compromised quality and quantity of saliva and impaired swallowing function, which can result in deleterious effects on nutritional status. Optimising nutrition status is critical, as malnutrition is adversely associated with treatment tolerance and outcomes, wound healing, morbidity, mortality, quality of life and survival. Dietitians are integral members of the HNC multidisciplinary team and are uniquely qualified in the assessment, management and optimisation of nutritional status across the care pathway. This includes providing informational counselling to patients and carers on the short- and long-term nutritional impact of planned treatments alongside multidisciplinary members. Dietitians lead on the recommendation, provision and monitoring of nutrition support, which can be via the oral, enteral or parenteral route. Oral nutrition support includes dietary counselling, nourishing dietary, food fortification advice and high energy/protein oral nutritional supplements. Enteral nutrition support, or tube feeding, can be required on a short- and/or long-term basis and dietitians support appropriate decision-making for the type of tube and timing of placement across the care pathway.

Effect of a Short-Term Intervention with Lactobacillus salivarius Probiotic on Early Childhood Caries-An Open Label Randomized Controlled Trial

ECC is a significant therapeutic and social problem and a global burden on public health. The aim of this clinical trial was to test whether a 2-week daily consumption of chewing tablets containing thermally inactivated L. salivarius reduces the 12-month caries increment compared to the control group. The investigation was a single-center, randomized, controlled open-label, blinded end-point evaluation trial in two parallel groups. At baseline, 140 generally healthy children between 3 and 6 years of age with or without ECC were randomly assigned to the probiotic test group (n = 70) or to the treatment as the usual control group (n = 70). The primary outcome measure was the 1-year increment in caries incidence and prevalence. Secondary endpoints assessed were the initial, cavitated and obvious dentinal caries increment as well as the measurement of dental plaque accumulation, as an indicator of the ECC risk. Data were collected through the clinical assessment of the children's caries (dmft and ICDAS II) and oral hygiene status (DI-S of OHI-S index). Caries incidence and prevalence were statistically significantly lower in the probiotic group versus the control group (p < 0.001 and p = 0.0075). The initial and final mean OHI-S scores in the probiotic group did not show any significant differences. In conclusion, the regular short-term intake of probiotics may reduce caries development. Our findings suggest that self-administered probiotic therapy may provide a good complement to increase the effectiveness of individual preventive home care in preschool children. This is the first clinical study evaluating the effect of a short-term probiotic intervention on reducing early childhood caries with 12 months of follow-up.

Sponsorship Bias in Clinical Trials in the Dental Application of Probiotics: A Meta-Epidemiological Study

Many experimental and clinical trials have investigated the dental application of probiotics, although the evidence concerning the effects of probiotic supplements is conflicting. We aimed to examine whether sponsorship in trials about dental applications of probiotics is associated with biased estimates of treatment effects. Overall, 13 meta-analyses involving 48 randomized controlled trials (23 with high risk of sponsorship bias, 25 with low risk) with continuous outcomes were included. Effect sizes were calculated from differences in means of first reported continuous outcomes, divided by the pooled standard deviation. For each meta-analysis, the difference in standardized mean differences between high-risk and low-risk trials was estimated by random effects meta-regression. Differences in standardized mean differences (DSMDs) were then calculated via meta-analyses in a random effects meta-analysis model. A combined DSMD of greater than zero indicated that high-risk trials showed more significant treatment effects than low-risk trials. The results show that trials with a high risk of sponsorship bias showed more significant intervention effects than did low-risk trials (combined DSMD, 0.06; 95% confidence interval, 0.3 to 0.9; p < 0.001), with low heterogeneity among meta-analyses (I2 = 0%; between-meta-analyses variance τ2 = 0.00). Based on our study, high-risk clinical trials with continuous outcomes reported more favorable intervention effects than did low-risk trials in general.

The Effect of Probiotics Use on Salivary Cariogenic Bacteria in Orthodontic Patients with Various Caries Risk Status

Background: The purpose of this study was to evaluate the change in intraoral cariogenic bacteria density after probiotic use in patients with orthodontic treatment, and to compare the impact of probiotics in patients with various caries risk status. Methods: Patients that planned to receive orthodontic treatment were recruited according to this study’s inclusion/exclusion criteria. A probiotic prescription (Lactobacteria 3 mg, Glycobacteria 2 mg) was started one month after the initial orthodontic treatment. Saliva sampling and cultures using a CRT kit (caries risk test) were performed at three time points (T0, T1, T2). Mutans streptococci (MS) and Lactobacilli (LB) density were evaluated and scored using the interpretation chart in the CRT kit to evaluate the change in bacteria density at three time points, to define the high and low caries risk prior to orthodontic treatment, and to evaluate if there were differences in probiotics between the high and low caries risk groups. Results: Thirty-three orthodontic patients were enrolled, twenty-two classified as high caries risk and eleven as low caries risk. After undergoing treatment for one month, the densities of MS and LB increased significantly (p = 0.011, p = 0.001); probiotics for one month decreased the density of MS and LB, but the differences were statistically nonsignificant (p = 0.109, p = 0.109). Patients classified as low risk of caries demonstrated an increase in MS and LB density one month after orthodontic treatment (p = 0.024, p = 0.001), probiotic use did not result in a significant reduction in bacteria density (p = 1000, p = 0.933). In patients with high caries risk, there were no statistically significant changes in MS count between the three time points (p = 0.127); a significant change in LB density occurred at T0–T1 (p = 0.011) only. Conclusions: Supplemental use of probiotic oral tablets during orthodontic treatment aimed at reducing cariogenic bacteria count in saliva did not achieve significant differences, regardless of patients’ risk status for caries.

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.

Comparing the prevalence of Helicobacter pylori and virulence factors cagA, vacA, and dupA in supra-gingival dental plaques of children with and without dental caries: a case-control study

BACKGROUND

Helicobacter pylori infection is one of the most common infectious diseases in humans. Dental plaque is considered as a reservoir of this bacterium, which could play an important role in the development of gastrointestinal problems. Our aim was to investigate the prevalence of H. pylori and its virulence factors in dental plaques in children with and without dental caries.

METHODS

Among children aged 6 to 12 years, a total of 72 children were enrolled in the study, including 36 cases with total DMFT/dmft > 3 (case group) and 36 participants with total DMFT/dmft < 1 (control group). After removing supra-gingival plaques from the lower first permanent molar teeth, the samples were examined using PCR method for the presence of H. pylori and some of its virulence factors. Statistical analysis was performed using chi-square, Fisher' exact test, t-tests, and logistic regression.

RESULTS

Of 72 participants, 40 cases were male, and 32 cases were female. The minimum and maximum values of total DMFT/dmft indices were zero and ten, respectively, and the mean ± SD value of total DMFT/dmft was 2.78 ± 3.22. Except for vegetable consumption (p = 0.045), there was no significant difference between the two groups regarding gastrointestinal disorders, feeding methods in infancy (p = 0.058), frequency of daily brushing (p = 0.808), frequency of dental visits (p = 0.101), and history of dental scaling (p = 0.246) and professional topical fluoride therapy (p = 0.5). Out of 72 samples, 15 cases were positive for H. pylori DNA (20.8%), and there was no significant association between the presence of this bacterium in dental plaque and dental caries (p = 0.281). The frequency of virulence factors detected in 15 H. pylori cases was as follows: cagA in six cases (40.0%), vacAm1 in three cases (20.0%), and vacAs1 in one case (6.7%). There was no significant difference between the groups regarding the prevalence of virulence factors.

CONCLUSION

Our results indicate the presence of H. pylori along with some virulence factors in dental plaques as a reservoir of this bacterium in children in Iran. Although there was no significant association between this bacterium and the incidence of dental caries, dental health in children needs to be seriously taken into consideration.

Effectiveness of the Lorodent Probiotic Lozenge in Reducing Plaque and Streptococcus mutans Levels in Orthodontic Patients: A Double-Blind Randomized Control Trial

Orthodontic patients are at a significant risk for oral diseases due to increased plaque accumulation and oral bacterial dysbiosis. We aimed to determine the efficacy of the commercially available Lorodent Probiotic Complex at reducing plaque accumulation and Streptococcus mutans bacterial levels in adolescent orthodontic patients. Sixty adolescents undergoing fixed orthodontic treatment for a minimum of 6 months were recruited in a randomized, double-blind, parallel-group, placebo-controlled trial. They received either Lorodent probiotic lozenge (intervention, n = 30) or placebo lozenge (control, n = 30) orally every day for a 28-day administration period. Participants were assessed at four appointments (T1–T4) over a total of 56 days. Compliance and lozenge satisfaction were monitored. Saliva samples and supragingival plaques were collected for evaluation of S. mutans levels. Clinical assessment using a Plaque Index (PI) was used. Compliance with lozenge intake of all participants was over 90%. There was no significant change in the PI and composite PI scores in both placebo and probiotic groups at each time frame (all p &gt; 0.05) or the relative S. mutans DNA levels in the saliva and plaque between the probiotic and placebo groups. The findings of high compliance and satisfaction with the probiotic lozenges combined with the study's rigorous design offer a baseline for subsequent testing of further potential probiotics (of varying formulations, concentrations), especially in adolescents.

Yogurt product intake and reduction of tooth loss risk in a Japanese community

Aim

To evaluate the longitudinal association between yogurt product intake and oral health in a population‐based study.

Materials and Methods

This study included 1967 Japanese residents aged 40–79 years who underwent dental examinations in 2012. Among them, 1469 participants were followed up in 2017 for the incidence of tooth loss, which was defined as two or more teeth lost over 5 years. The intake of yogurt products, defined as yogurt and lactic acid beverages, was estimated using a semi‐quantitative food frequency questionnaire. The composition of the salivary microbiota was evaluated.

Results

The Poisson regression model showed that a higher intake of yogurt products was negatively associated with the incidence of tooth loss (p for trend = .020), adjusted for potential confounding factors. Mediation analysis confirmed that periodontal condition partly mediated the effect of yogurt product intake on tooth loss, while dental caries experience did not. Additionally, we confirmed the association of a high intake of yogurt products with a low percentage of the salivary microbiota pattern, which was associated with poor oral health.

Conclusion

These findings suggest that the intake of yogurt products is associated with a lower risk of tooth loss resulting from periodontal disease, probably via modulation of the oral microbiome composition.

The Effect of Oral Probiotics (Streptococcus Salivarius k12) on the Salivary Level of Secretory Immunoglobulin A, Salivation Rate, and Oral Biofilm: A Pilot Randomized Clinical Trial

We aimed to assess the effect of oral probiotics containing the Streptococcus salivarius K12 strain on the salivary level of secretory immunoglobulin A, salivation rate, and oral biofilm. Thirty-one consenting patients meeting the inclusion criteria were recruited in this double-blind, placebo-controlled, two-arm, parallel-group study and randomly divided into probiotic (n = 15) and placebo (n = 16) groups. Unstimulated salivation rate, concentration of salivary secretory immunoglobulin A, Turesky index, and Papillary-Marginal-Attached index were assessed after 4 weeks of intervention and 2 weeks of washout. Thirty patients completed the entire study protocol. We found no increase in salivary secretory immunoglobulin A levels and salivary flow rates in the probiotic group compared with placebo. Baseline and outcome salivary secretory immunoglobulin A concentrations (mg/L) were 226 ± 130 and 200 ± 113 for the probiotic group and 205 ± 92 and 191 ± 97 for the placebo group, respectively. A significant decrease in plaque accumulation was observed in the probiotic group at 4 and 6 weeks. Within the limitations of the present study, it may be concluded that probiotic intake (Streptococcus salivarius K12) does not affect salivation rates and secretory immunoglobulin A salivary levels but exhibits a positive effect on plaque accumulation. Trial registration NCT05039320. Funding: none.

Virulence of Lactobacillus spp. misidentified as Enterococcus faecalis from children's carious dentine

Objective: This study aimed to search for Enterococcus faecalis in children's deep carious dentine and characterize their virulence traits.Material and Methods: Eight isolates from 15 carious molars identified by 16S rDNA species-specific PCR as E. faecalis were included. These eight isolates were subject to identification by MALDI-TOF and characterized regarding: (i) bacterial aggregation and biofilm formation on polystyrene and glass, with/without saliva, as single or dual-species (associated to Streptococcus mutans); (ii) environmental pH measurement before and after 24 h incubation; (iii) acidogenicity; (iv) gelatinase production; (v) macrophage adherence; and (vi) toxicity towards Caenorhabditis elegans. Statistical analyses were performed using two-way ANOVA/Tukey or Fisher's exact tests.Results: All isolates initially identified as E. faecalis by PCR were correctly identified as Lactobacillus by MALDI-TOF, being designated as Lactobacillus misidentified as Enterococcus (LME). These isolates produced biofilm in the presence of saliva and in the dual-species assays. Bacterial aggregation was only observed in the dual-species model. After 24 h, environmental pH dropped from 7.5 to 4.5 for seven of eight isolates, and to 4.0 in all dual-species models. LME isolates were acidogenic, none of them produced gelatinase or adhered to macrophages, but all presented toxicity towards C. elegans.Conclusions: No E. faecalis were identified in the children's caries lesions. All LME isolates presented important virulence traits, including biofilm formation and high acidogenicity, which cause enamel demineralization, that might increase the risk of dental caries in children carrying LME. Thus, the correct identification and in-depth virulence characterization of microorganisms isolated from dental caries are important to understand the dynamics of this disease.

Effectiveness and safety of Bifidobacterium in preventing dental caries: a systematic review and meta-analysis

OBJECTIVES

The effectiveness and safety of Bifidobacterium in dental caries prevention are controversial. Thus, we performed this systematic review and meta-analysis to explore the preventive value of Bifidobacterium.

METHODS

Eligible studies were identified from several databases, including PubMed, the Cochrane Library, Embase, Web of Science, and Scopus. Hand searches were also conducted in relevant bibliographies. We then extracted and pooled standardized mean difference (SMD) and risk ratio (RR) to analyze the anti-caries effect of Bifidobacterium with Stata 16.0 software. If the data obtained was not suitable for meta-analysis, qualitative descriptions were performed.

RESULTS

Compared with the placebo control group, there was no statistically significant reduction in Streptococcus mutans and Lactobacilli counts in saliva in the test group. Also, there were no significant differences in Streptococcus mutans and Lactobacillus counts in dental plaque and no significant difference in caries incidence in deciduous teeth. There was no significant difference in the incidence of adverse events between the Bifidobacterium and control groups.

CONCLUSIONS

Available evidence demonstrates that Bifidobacterium is neither effective in reducing Streptococcus mutans and Lactobacillus counts in the saliva or dental plaque nor in reducing the occurrence of caries in deciduous teeth. Evaluation of its safety requires further investigations. Therefore, Bifidobacterium is not a competent probiotic candidate to prevent dental caries.

Tapioca Starch Modulates Cellular Events in Oral Probiotic Streptococcus salivarius Strains

Considering the implications of microbiota in health, scientists are in search of microbiota-oriented strategies for the effective prevention and/or treatment of a wide variety of serious diseases. A microbiota comprises diverse microorganisms with either probiotic or pathogenic properties. The fermentation of prebiotic carbohydrates by probiotic bacteria can affect host metabolism. Therefore, understanding the prebiotic-mediated metabolic modulations in probiotics is crucial to develop functional foods for the improvement of disturbed microbiota. Studies have emphasized the importance of prebiotics in probiotic therapies for mucosal diseases and highlighted the need for extensive research on oral bacteria. In the present study, the cellular events have been studied in batch cultures of probiotic Streptococcus salivarius exposed to the natural prebiotic, tapioca starch (TS). TS modulated the keystone metabolic events in Streptococcus salivarius in a dose-dependent manner. Besides increasing the live cell counts and altering the colony morphologies, TS affected the protein metabolism in terms of cellular expression and conformational changes in protein secondary structures. After treatment with TS, the nucleic acid synthesis increased and B-DNA was more than A- and Z-DNA, together with the diminished fatty acids and increased polysaccharide synthesis. The study results can be considered for the assessment of functional foods and probiotics in oral health.

Can probiotic supplements prevent early childhood caries? A systematic review and meta-analysis

The aim of this study was to explore the preventive effect of probiotic supplements on the development of early childhood caries (ECC). We searched the PubMed, Google Scholar and Cochrane databases up to January 15, 2021. The authors screened the hits independently for relevance, extracted outcome data and assessed the risk of bias. We performed a random effects meta-analysis to pool and compare the incidence of ECC in children assigned to test or placebo groups, respectively. The authors included nine randomised controlled trials published between 2001 and 2021, involving 2,363 preschool children. We assessed two publications with a moderate risk of bias and seven with high risk of bias. The median caries incidence in the probiotic test groups was 8.5% compared with 17.5% in the placebo groups and this difference was statistically significant (P<0.001). A pooled random effects meta-analysis on caries incidence on subject level showed a small but statistically significant risk difference in favour of the probiotic intervention (-0.05, 95% confidence interval (CI) -0.10, -0.00; P<0.05). The mean difference in caries increment on tooth/surface level was -0.57, (95% CI -0.91, -0.23; P<0.01). In conclusion, we demonstrated a small but statistically significant preventive effect of probiotic supplements on ECC. However, the certainty of this finding was low due to the risk of bias, heterogeneity and inconsistencies across the studies. Further long-term randomised controlled trials with low risk of bias are required in order to answer the research question with a higher certainty.

Global Review of Dairy Recommendations in Food-Based Dietary Guidelines

At present, there are ~100 countries with national food-based dietary guidelines. While the intent of these guidelines is to inform national-level dietary recommendations, they also tie into global health and sustainable development initiatives, since diet and nutrition are linked to outcomes for all 17 United Nations Sustainable Development Goals. Therefore, key messaging in food-based dietary guidelines plays an important role in both national and global health efforts. However, this type of national-level dietary guidance is not standardized and varies considerably from country to country, and from food group to food group. The main objective of this review is to provide a novel look at dairy food group messaging within global food-based dietary guidelines, focusing specifically on nutrient-based and health-based messaging. Dairy-based messaging from 94 national food-based dietary guidelines was reviewed and grouped by region, with an emphasis on messaging regarding dairy's contribution to nutrients of public health concern for both underconsumption and overconsumption. The results showed that most nutrient-based dairy messaging relating to underconsumption was focused on calcium, followed by vitamin D, iodine, potassium, and protein; whereas messaging related to overconsumption was focused on saturated fat, added sugars, and salt. Health-based messaging specific to dairy food intake typically coalesced around three types of health outcomes: (1) bone, teeth, and muscle, (2) cardiometabolic, and (3) gut and immune. Although a fundamental concept of food-based dietary guidelines is to provide dietary guidance in a manner that is both “food-based,” and in the context of “dietary” patterns, most food-based dietary guidelines still express the health value of dairy foods (and potentially other foods groups) solely in terms of their nutrient content – and often times only in the context of a single nutrient (e.g., calcium).

Probiotic fermented milks: Children's emotional responses using a product-specific emoji list

This study aimed to develop and validate a product-specific emoji list and use this list to analyse children's emotional responses associated with the consumption of probiotic fermented milks prepared with different probiotic strains. Furthermore, the overall liking of the products was studied during a sensory test. Six formulations were studied: Bifidobacterium BB12 (BB), Lactobacillus acidophilus L3 (LA3), Lactobacillus acidophilus LA 05 (LA5), Lactobacillus delbrueckii subsp. lactis (LL), Lacticaseibacillus casei 01 (LC), and Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus (CONV). A total of 132 children (7-14 years old) participated in two study phases: development (n = 32) and validation (n = 100) of the list. Fifteen emoji were selected to be included in the product-specific list, which had a high frequency of citations in the first phase. The formulations with the highest overall liking (LL, BB, LC and CONV) were correlated with positive emoji, while the least-liked formulations (LA3 and LA5) were associated with negative emoji. Furthermore, the utilisation of emoji enabled the differentiation among formulations with similar overall liking. Therefore, this study developed and validated an emoji list to be used in the evaluation of fermented milks by children. The results suggest that the type of probiotic culture impacted the sensory characteristics of fermented milks, supporting the use of Bifidobacterium, L. lactis or L. casei in these products.

Efficacy of Probiotic Milk for Caries Regression in Preschool Children: A Multicenter Randomized Controlled Trial

This multicenter double-blind randomized controlled trial aimed to determine the efficacy of daily or triweekly consumption of reconstituted milk powder, containing <i>Lactobacillus paracasei</i>SD1, in preschool children for caries prevention. A 6-month intervention was conducted in 487 children (aged 37.6 ± 9.2 months) with ≤4 decayed teeth from 8 childcare centers. Using stratified block randomization, participants were randomly allocated into 3 groups, comprising: (1) daily probiotic, receiving probiotic milk once daily, (2) triweekly probiotic, randomly receiving probiotic milk 3 days a week and the placebo milk for the remaining 4 days, and (3) placebo, receiving milk without probiotics. Each tooth surface was assessed for caries status using the modified Nyvad criteria at baseline (T0), 6 (T6) and 12 (T12) months after T0. Study outcomes were caries transition, including caries progression and regression during the T0–T6, T6–T12 and T0–T12 periods. Negative binomial regression with a generalized linear model was used to estimate the caries outcomes, which were reported as incidence rate ratios (IRRs) and 95% confidence intervals (CIs). At baseline, caries prevalence and mean decayed surfaces were 81.9% and 7.29 ± 7.60, respectively. Three groups were balanced at baseline with an overall dropout rate of 25.2%. After adjusting for age, sex, and the number of noncavitated and cavitated caries at baseline, a decreased caries risk during T0–T6 was shown in both the daily and triweekly probiotic groups (adjusted IRR 0.83, 95% CI 0.72–0.96 in both groups) and during T0–T12 (adjusted IRR 0.84, 95% CI 0.76–0.94, and adjusted IRR 0.86, 95% CI 0.76–0.96, respectively) compared to the placebo group. In contrast, significantly increased regressive surfaces were demonstrated during T0–T6 by adjusted IRR 1.76 (95% CI 1.25–2.48) and 2.01 (95% CI 1.42–2.85) and during T0–T12 by adjusted IRR 1.98 (95% CI 1.50–2.61) and 1.92 (95% CI 1.45–2.55) for the daily and triweekly groups, respectively. In conclusion, probiotic milk consumption either daily or triweekly can modestly prevent new caries, but considerably reverse carious lesions, suggesting that a daily or triweekly dose interval is sufficient to reverse carious lesions.

Reliability of MALDI-TOF mass spectrometry to identify oral isolates of Streptococcus salivarius and Lactobacillus spp

OBJECTIVE

The aim of this study is to evaluate the performance of MALDI-TOF mass spectrometry in identifying bacteria isolated in the oral cavity known to be of probiotic interest.

DESIGN

We evaluated Bruker MALDI Biotyper for the identification of 92 clinical oral isolates of probiotic interest (31 Streptococcus salivarius and 61 Lactobacillus spp.) by comparing direct colony method with on-plate formic acid extraction. Isolates were previously identified by use of biochemical methods and molecular biology.

RESULTS

Using the manufacturer's suggested genus and species level cutoff scores, the direct colony method identified 42 (45.7%) isolates at the genus level and 35 (38%) at the species level while the on-plate extraction method correctly identified 90 (97.8%) isolates at the genus level and 82 (89.1%) at the species level. The difference between the two methods was statistically significant at the genus and species levels (P ≤ 0.0001). After dividing the isolates into two subgroups, the analysis was repeated. The direct colony method identified correctly all isolates of Streptococcus salivarius at the species level. In contrast, the direct colony method allowed the identification of only 11 (18%) lactobacilli at the genus level and 4 (6.6%) at the species level. The on-plate extraction method was statistically (P ≤ 0.0001) more efficient since 59 (96.7%) lactobacilli were identified at the genus level and 51 (83.6%) at the species level.

CONCLUSIONS

MALDI Biotyper can efficiently identify Streptococcus salivarius regardless of the preparative method but on-plate extraction is superior to direct colony method for the identification of lactobacilli.

The stability of children's salivary peptidome profiles in response to short-term beverage consumption

BACKGROUND

Salivary peptidome profiling analysis has advantages of simplicity and non-invasiveness and great potentiality for screening, monitoring or primary diagnosis of diseases, but may be subjected to change against interferences like diet.

METHODS

We conducted a 5-day study to investigate the influence of 3 kinds of beverages (orange juice, sugar-free tea, and sugar-free liquid yoghurt; water as control) on children's salivary peptidome using mass spectrometry techniques.

RESULTS

All the groups shared a relatively stable pattern in heatmaps during the experimental days. Principal component analysis plot presented slight shifts in all the intervention groups between the baseline and intervention period while samples were not distinctly separated by date. The numbers of significantly changed peptides after short-term orange juice and tea intervention were four and three, respectively, while no changes occurred in the yoghurt group and control. Four of these peptides were identified as histatin-3, collagen alpha-1(IV) chain, zinc finger protein 805, and quinolinate synthase A.

CONCLUSIONS

Salivary peptidome has its own stability against beverage intervention, confirming the feasibility and validity of using it as a potential reference for the healthy state of the body, with diet habits recorded and considered as a confounder if necessary.

Do probiotics promote oral health during orthodontic treatment with fixed appliances? A systematic review

BACKGROUND

Treatment with fixed orthodontic appliances has been associated with significant biofilm accumulation, thus putting patients at a higher risk of oral health deterioration. The use of probiotics has been proposed to be useful in the prevention or treatment of oral pathologies such as caries and diseases of periodontal tissues. Our aim was to investigate the effects of probiotic use on inflammation of the gingival tissues and the decalcification of the enamel in patients being treated with fixed orthodontic appliances.

METHODS

We searched without restrictions 8 databases and performed hand searching until September 2019. We searched for randomized controlled trials (RCTs) evaluating whether individuals with fixed orthodontic appliances benefit from probiotic treatment in terms of the inflammation of the gingivae and decalcification of the enamel. Following the selection of studies and the extraction of pertinent data, we appraised the risk of bias and the confidence in the observed effects based on established methodologies.

RESULTS

From the final qualifying studies, three did not show any statistically significant effect on gingival inflammation after probiotic administration of up to 1 month. Similarly, non-significant differences were noted in another study regarding white spot lesions development (mean administration for 17 months). No adverse effects were reported and the level of evidence was considered moderate.

CONCLUSIONS

Supplementation of orthodontic patients with probiotics did not affect the development of inflammation in the gingivae and decalcification in the enamel. Additional RCTs, with longer intervention and follow-up periods, and involving different combinations of probiotic strains are required.

TRIAL REGISTRATION

PROSPERO (CRD42018118008).

Adhesion, anti-adhesion and aggregation properties relating to surface charges of selected Lactobacillus strains: study in Caco-2 and H357 cells

This study aimed to assess adhesion and anti-adhesion, aggregation, and surface properties of four selected oral Lactobacillus strains, L. fermentum SD7, L. paracasei SD1, L. rhamnosus SD4, and L. rhamnosus SD11, together with Lactobacillus rhamnosus GG. Human cells, enterocytes Caco-2 and oral keratinocyte H357 were used, and various enteric and oral pathogens were included. Results showed that all Lactobacillus tested gave high adhesion and internalization in both Caco-2 and H357 cells similar to L. rhamnosus GG, and it suggests that such properties are strain dependent and specific to host cells. Anti-adhesion was different; it depended on the internalization ability of individual Lactobacillus and pathogenic strains to Caco-2 and H357. Coaggregation ability depended on autoaggregation of both the Lactobacillus and pathogenic strains. A positive correlation between surface charges and aggregation, and internalization and anti-adhesion of all Lactobacillus was found. In conclusion, results suggests that the selected Lactobacillus might be potential probiotics for usage in both the oral cavity and intestinal tract due to their abilities of aggregation, adherence and anti-internalization to both Caco-2 and H357 cells.

Current Evidence of Natural Agents in Oral and Periodontal Health

Oral and periodontal diseases, chewing disorders, and many destructive inflammatory diseases of the supporting tissues of the teeth are usually caused by an imbalance between host defense and environmental factors like smoking, poor nutrition, and a high percentage of periodontopathogenic bacteria. For these reasons, it is important also to focus attention on plaque control and also on improving host resistance through smoking and stress reduction, and a healthy diet. During the last decades, the importance of micronutrients has been extensively reviewed, and it was concluded that the prevention and treatment of periodontitis should include correct daily nutrition and a correct balance between antioxidants, probiotics, natural agents, vitamin D, and calcium. Recently, there has been growing interest in the literature on the impact of nutraceutical dietary aliments on oral and general health. This Special Issue provides a current and thoughtful perspective on the relationship of diet and natural agents on oral and periodontal diseases through a correct clinical approach with the last and most important evidence that may determine good oral conditions and high quality of life.

Antibiotics and Antimicrobials for Treatment of the Oral Microbiota: Myths and Facts in Research and Clinical Practice

In the dental field, the most common oral diseases include periodontitis, apical periodontitis, abscesses, phlegmons and pulpits, all of which are determined by the same aetiological factor, bacterial infections. For these reasons, it is important to choose the right approach through a target antibiotic therapy against oral bacteria. More specifically, during periodontitis, antibiotics are used, often in association with periodontal debridement, to reduce disease-associated periodontopathogens. However, international guidelines are not unanimous in recommending the use of local and/or systemic antimicrobials to reduce infection by oral bacteria, especially in cases in which there is a danger of spreading systemic infection such as cellulitis, diffuse swelling, and abscesses. The lack of consensus is mainly due to the side effects of antibiotic therapy in dentistry, maybe due to recent scientific evidence regarding the development of bacterial resistance to antibiotics. Therefore, the purpose of this editorial is to analyze the therapeutic effects of antibiotics against the main forms of oral and periodontal diseases, and whether there is a significant clinical benefit, especially in the long term, of antimicrobial therapies in dentistry. The most recent evidence regarding antimicrobial agents will also be discussed.

Comparative Evaluation of Plaque Inhibitory and Antimicrobial Efficacy of Probiotic and Chlorhexidine Oral Rinses in Orthodontic Patients: A Randomized Clinical Trial

Background

Antimicrobial agents serve as an effective adjunct in plaque control, and chlorhexidine has been the gold standard. However, the philosophy that natural agents are better for children's oral health is on the rise. Probiotic technology represents a breakthrough approach to maintain oral health by utilizing natural beneficial bacteria commonly found in healthy mouths.

Aim and Objective

To compare efficacy of probiotic and chlorhexidine oral rinses in orthodontic patients.

Materials and Methods

30 healthy patients undergoing fixed orthodontic treatment were randomly selected for the study by block randomization and allocation concealment and were divided into three groups: group a, 0.2% chlorhexidine mouthwash; group b, probiotic mouthwash; and group c, a control group.

Results

Probiotic and chlorhexidine groups had significantly decreased plaque indices as compared to the control group. However, greater improvement was seen in the gingival indices than plaque indices with better results in the probiotic group than the chlorhexidine group. No statistical significance was observed in the streptococcus count of probiotic and chlorhexidine groups at the end of the intervention period.

Conclusion

The comparison of probiotics to chlorhexidine has proven that probiotics are as effective as chlorhexidine as an adjunctive chemical plaque control agent.