The effect of Bacillus subtilis mouth rinsing in patients with periodontitis

Effect of Probiotic Supplements on the Oral Microbiota-A Narrative Review

Data from systematic reviews and meta-analyses show that probiotics positively impact clinical parameters of oral diseases such as gingivitis, dental caries, and periodontitis. However, the working mechanism of probiotics is not fully understood, but is hypothesized to be mediated by direct and indirect interactions with the oral microbiota and the human host. In the present narrative review, we focused on the microbiological effect of probiotic supplements based on data retrieved from randomized clinical trials (RCTs). In addition, we assessed to what extent contemporary molecular methods have been employed in clinical trials in the field of oral probiotics. Multiple RCTs have been performed studying the potential effect of probiotics on gingivitis, dental caries, and periodontitis, as evaluated by microbial endpoints. In general, results are conflicting, with some studies reporting a positive effect, whereas others are not able to record any effect. Major differences in terms of study designs and sample size, as well as delivery route, frequency, and duration of probiotic consumption, hamper comparison across studies. In addition, most RCTs have been performed with a limited sample size using relatively simple methods for microbial identification, such as culturing, qPCR, and DNA-DNA checkerboard, while high-throughput methods such as 16S sequencing have only been employed in a few studies. Currently, state-of-the-art molecular methods such as metagenomics, metatranscriptomics, and metaproteomics have not yet been used in RCTs in the field of probiotics. The present narrative review revealed that the effect of probiotic supplements on the oral microbiota remains largely uncovered. One important reason is that most RCTs are performed without studying the microbiological effect. To facilitate future systematic reviews and meta-analyses, an internationally agreed core outcome set for the reporting of microbial endpoints in clinical trials would be desirable. Such a standardized collection of outcomes would most likely improve the quality of probiotic research in the oral context.

Nutritional factors influencing microbiota-mediated colonization resistance of the oral cavity: A literature review

The oral cavity is a key biocenosis for many distinct microbial communities that interact with both the external environment and internal body systems. The oral microbiota is a vital part of the human microbiome. It has been developed through mutual interactions among the environment, host physiological state, and microbial community composition. Indigenious microbiota of the oral cavity is one of the factors that prevent adhesion and invasion of pathogens on the mucous membrane, i.e., the development of the infectious process and thereby participating in the implementation of one of the mechanisms of local immunity-colonization resistance. The balance between bacterial symbiosis, microbial virulence, and host resistance ensures the integrity of the oral cavity. In this review we have tried to address how nutritional factors influence integrity of the oral indigenous microbiota and its involvement in colonization resistance.

Nisin probiotic prevents inflammatory bone loss while promoting reparative proliferation and a healthy microbiome

Dysbiosis of the oral microbiome mediates chronic periodontal disease. Realignment of microbial dysbiosis towards health may prevent disease. Treatment with antibiotics and probiotics can modulate the microbial, immunological, and clinical landscape of periodontal disease with some success. Antibacterial peptides or bacteriocins, such as nisin, and a nisin-producing probiotic, Lactococcus lactis, have not been examined in this context, yet warrant examination because of their biomedical benefits in eradicating biofilms and pathogenic bacteria, modulating immune mechanisms, and their safety profile in humans. This study's goal was to examine the potential for nisin and a nisin-producing probiotic to abrogate periodontal bone loss, the host inflammatory response, and changes in oral microbiome composition in a polymicrobial mouse model of periodontal disease. Nisin and a nisin-producing Lactococcus lactis probiotic significantly decreased the levels of several periodontal pathogens, alveolar bone loss, and the oral and systemic inflammatory host response. Surprisingly, nisin and/or the nisin-producing L. lactis probiotic enhanced the population of fibroblasts and osteoblasts despite the polymicrobial infection. Nisin mediated human periodontal ligament cell proliferation dose-dependently by increasing the proliferation marker, Ki-67. Nisin and probiotic treatment significantly shifted the oral microbiome towards the healthy control state; health was associated with Proteobacteria, whereas 3 retroviruses were associated with disease. Disease-associated microbial species were correlated with IL-6 levels. Nisin or nisin-producing probiotic's ability to shift the oral microbiome towards health, mitigate periodontal destruction and the host immune response, and promote a novel proliferative phenotype in reparative connective tissue cells, addresses key aspects of the pathogenesis of periodontal disease and reveals a new biomedical application for nisin in treatment of periodontitis and reparative medicine.

Probiotics, Their Extracellular Vesicles and Infectious Diseases

Probiotics have been shown to be effective against infectious diseases in clinical trials, with either intestinal or extraintestinal health benefits. Even though probiotic effects are strain-specific, some "widespread effects" include: pathogen inhibition, enhancement of barrier integrity and regulation of immune responses. The mechanisms involved in the health benefits of probiotics are not completely understood, but these effects can be mediated, at least in part, by probiotic-derived extracellular vesicles (EVs). However, to date, there are no clinical trials examining probiotic-derived EVs health benefits against infectious diseases. There is still a long way to go to bridge the gap between basic research and clinical practice. This review attempts to summarize the current knowledge about EVs released by probiotic bacteria to understand their possible role in the prevention and/or treatment of infectious diseases. A better understanding of the mechanisms whereby EVs package their cargo and the process involved in communication with host cells (inter-kingdom communication), would allow further advances in this field. In addition, we comment on the potential use and missing knowledge of EVs as therapeutic agents (postbiotics) against infectious diseases. Future research on probiotic-derived EVs is needed to open new avenues for the encapsulation of bioactives inside EVs from GRAS (Generally Regarded as Safe) bacteria. This could be a scientific novelty with applications in functional foods and pharmaceutical industries.

Oral probiotic and its delivery carriers to improve oral health: A review

In recent years, oral probiotics have been researched on their effectiveness in reducing and preventing oral diseases. Oral probiotics could be introduced into the oral cavity to keep the equilibrium of the microbiome. Hence, the delivery carrier for oral probiotics plays an important factor to ensure a high number of oral probiotics were delivered and released into the oral cavity. This review presents a brief overview of oral microbiota and the role of oral probiotics in reducing oral diseases. Moreover, important aspects of the oral probiotic product such as viability, adherence ability, health effects, safety, and delivery site were discussed. Besides that, the importance of utilizing indigenous oral probiotics was also emphasized. Oral probiotics are commonly found in the market in the form of chewing tablets, lozenges, and capsules. Hence, the oral probiotic carriers currently used in the market and research were reviewed. Furthermore, this review introduces new potential oral probiotic delivery carriers such as oral strip, bucco-adhesive gel, and mouthwash. Their effectiveness in delivering oral probiotics for oral health was also explored.

Efficiency of Bacillus subtilis metabolism of sugar alcohols governs its probiotic effect against cariogenic Streptococcus mutans

Bacillus subtilis is a Gram-positive probiotic bacterium that successfully colonises plant roots due to its ability to utilise various sugars. The vast probiotic potential of B. subtilis has been recently demonstrated in numerous host organisms under different environmental conditions. We examined the probiotic potential of B. subtilis against the pathogenic bacterium Streptococcus mutans, which is involved in various oral disorders due to its robust biofilm-forming capability. B. subtilis cells attenuated biofilm formation by S. mutans during their dual growth in the presence of sugar alcohols. Transcription of genes encoding key enzymes in the metabolism of sugar alcohols by B. subtilis were highly induced. Moreover, growth-curve analysis suggested that B. subtilis is more efficient at early utilising sugar alcohols than S. mutans, as supported by the bacterial metabolic activity rates. Similarly, a comparison of secondary metabolites of mono and mixed cultures of B. subtilis and S. mutans indicated that B. subtilis is more active metabolically in the dual culture. Finally, knock-out mutations of the genes encoding key enzymes in the central metabolic pathway significantly reduced B. subtilis' ability to mitigate biofilm formation by S. mutans. We conclude that effective metabolism of sugar alcohols by B. subtilis reinforces the probiotic potential of this bacterium against pathogenic species such as S. mutans.

Can Probiotics Emerge as Effective Therapeutic Agents in Apical Periodontitis? A Review

Apical periodontitis (AP) is a biofilm-associated disease initiated by the invasion of dental pulp by microorganisms from the oral cavity. Eradication of intracanal microbial infection is an important goal of endodontic treatment, and this is typically accomplished by mechanical instrumentation and application of sodium hypochlorite and chlorhexidine. However, these agents are tissue-irritating at higher concentrations and cytotoxic. Certain probiotics have been found effective in controlling marginal periodontitis, as evidenced by reduction of pathogenic bacterial loads, gains in clinical attachment levels, and reduced bleeding on probing. In vitro studies have shown inhibitory activity of some probiotics against endodontic pathogens. Similarly, in vivo studies in rats have demonstrated a positive immuno-modulatory role of probiotics in AP, as manifested by decreased levels of proinflammatory markers and increased levels of anti-inflammatory markers. A role for probiotics in effecting a reduction of bone resorption has also been reported. This review provides an outline of current research into the probiotic management of AP, with a focus on understanding the mechanisms of their direct antagonistic activity against target pathogens and of their beneficial modulation of the immune system.

Probiotics, including nisin-based probiotics, improve clinical and microbial outcomes relevant to oral and systemic diseases

The effects of probiotic supplementation on systemic health and gastrointestinal diseases have been investigated in numerous studies. The aim of this review is to provide an overview of probiotics and their effects on periodontal health. Probiotics show beneficial effects as adjunctive therapeutics and as stand-alone agents in the treatment and prevention of gingivitis as well as specific clinical parameters of periodontitis. This review focuses on the clinical and microbiological aspects of probiotics in the context of health, gingivitis, and periodontitis. In addition, a special focus on nisin-producing probiotics and nisin itself showcase their significant potential for oral and systemic use.

Effect of synbiotics in the treatment of smokers and non-smokers with gingivitis: randomized controlled trial

BACKGROUND

To evaluate the efficacy of synbiotic tablets on the clinical and biochemical parameters of smokers and non-smokers with gingivitis.

METHODS

Eighty patients with gingivitis [40 smokers (+), 40 non-smokers (-)] were randomly assigned to test (T) or control (C) groups. Four groups were defined: T(+), T(-), C(+) and C(-). The subjects daily chewed a synbiotic or placebo tablet for 30 days. The gingival crevicular fluid levels of interleukin (IL)-6, IL-8 and IL-10 were determined as the primary outcome variables.

RESULTS

The clinical and biochemical parameters for all groups significantly reduced compared with the baseline (P < 0.05). While there were no significant differences between the groups for gingival index, the plaque index was significantly higher in both smoker groups than that in the T(-) group during the second month (P < 0.05). IL-8 levels in C(-) and IL-6 levels in both control groups were significantly higher than those in the T(+) group. The IL-10 levels in both control groups were significantly higher than those in the T(-) group during the second month (P < 0.05).

CONCLUSIONS

Adjunctive synbiotic tablets significantly reduce subclinical therapeutic outcomes for both smokers and non-smokers compared with placebo according to the biochemical parameters.

The dynamics of the oral microbiome and oral health among patients receiving clear aligner orthodontic treatment

OBJECTIVES

This 6-month prospective clinical study assessed the impacts of Invisalign appliances on the oral bacterial community and oral health of patients.

METHODS

Salivary samples were obtained from twenty-five adult patients receiving Invisalign aligner treatment before the treatment (Group B) and at a 6-month follow-up (Group P). The bacterial composition of each sample was determined using Illumina MiSeq sequencing of the bacterial 16S rRNA. Intra- and intergroup biodiversity was analyzed. Clinical periodontal parameters and daily oral hygiene habits were recorded.

RESULTS

Reduction in plaque, increased daily brushing frequency, and decreased dessert intake were observed in Group P compared with that in Group B. A total of 1,853,952 valid reads were obtained from the 50 salivary samples, with 37,904 sequences per sample. No significant differences were detected in the intra- and intergroup biodiversity comparisons between the two groups. By clustering, 8,885 OTUs were identified and categorized into six major phyla: Firmicutes, Proteobacteria, Bacteroidetes, Fusobacteria, Actinobacteria, and Candidate_division_TM7_norank. At the genus level, compared with Group B, Group P demonstrated significantly increased Bacillus abundance and decreased Prevotella abundance.

CONCLUSIONS

Our results suggested that the general biodiversity and salivary microbial community structure did not change significantly and that patients had increased beneficial oral hygiene habits and awareness during the first six months of Invisalign treatment. Hence, on the basis of this study, it appears that Invisalign aligner treatment did not induce deterioration of oral health nor significant biodiversity changes in oral bacterial communities, assuming that detailed oral hygiene instructions for both teeth and aligners were provided.

A comparative study of synbiotic as an add-on therapy to standard treatment in patients with aggressive periodontitis

Context:

The role of synbiotic in the management of aggressive periodontitis (AP) is not well established.

Aim:

We designed this study to evaluate the efficacy and safety of synbiotic as an add-on therapy in the management of AP.

Settings and Design:

This was a randomized, double-blind, placebo-controlled study.

Materials and Methods:

Sixty patients with AP were randomized to two groups of 30 each. Study group received standard treatment, i.e., scaling and root planing along with doxycycline 100 mg twice daily for the 1^st day (loading dose) followed by 100 mg once daily for 1 week and synbiotic lozenge twice daily for 8 weeks, whereas control group received standard treatment for 1 week and placebo lozenge for 8 weeks. Clinical parameters were recorded at baseline, 4^th, 8^th, and 12^th weeks.

Statistical Analysis Used:

Pearson's Chi-square test and one-way analysis of variance were used to analyze distribution of sex and age, respectively. Differences within the groups were analyzed by Student's paired t-test. Pearson's Chi-square test was applied to measure gingival bleeding index.

Results:

On comparison at 12 weeks, there was a statistically significant reduction (P < 0.01) in probing depth, clinical attachment loss, oral hygiene index, and bleeding on probing in study group. No Adverse drug reactions were noted.

Conclusion:

Co-administration of synbiotic lozenge along with standard therapy is highly efficacious in improving periodontal health in patients with AP.

Potential synergistic effects of a mixture of mineral trioxide aggregate (MTA) cement and Bacillus subtilis in dental caries treatment

Bacillus subtilis is nonpathogenic in humans and produces a number of useful substances and, therefore, this bacterium is used in probiotic therapy. There have been trials of B. subtilis for patients with periodontitis, but not for patients with caries. Similarly, mineral trioxide aggregate (MTA) cement has been widely used for endodontic treatment, but there are few reports of its use for caries. Therefore, examinations were performed regarding the benefits of addition of B. subtilis to MTA cement for treatment of dental caries. Indirect pulp capping with a mixture of MTA cement and B. subtilis spore powder is effective for avoiding pulpectomy or tooth extraction in such cases (personal communication). This study was planned to examine the scientific basis of this clinical finding, with examination of possible synergistic effects of MTA cement and B. subtilis. From these experiments, the following five results were obtained: (1) B. subtilis did not proliferate in liquid-culture media at pH ≥10. (2) B. subtilis proliferated when mixed with MTA cement. (3) There was no significant difference in proliferation of B. subtilis under aerobic and microaerobic conditions. (4) B. subtilis exhibited antibacterial effects on Staphylococcus aureus and Lactobacillus casei. (5) MTA cement exhibited antibacterial effects on S. aureus and Streptococcus mutans, but not on B. subtilis. These results support the hypothesis that a combination of B subtilis and MTA cement is likely to be clinically useful for treatment of dental caries.

Assessment of oral malodor and tonsillar microbiota after gargling with benzethonium chloride

The oropharyngeal area can be a source of halitosis. However, the relationship between healthy tonsillar microbiota and halitosis is poorly understood. We conducted a pilot clinical study to clarify the effect of gargling with an antiseptic agent on tonsillar microbiota in patients with halitosis. Twenty-nine halitosis patients who did not have otolaryngologic disease or periodontitis were assigned randomly to one of three groups: benzethonium chloride (BZC) gargle; placebo gargle; no gargle. Concentrations of volatile sulfur compounds (VSCs) in mouth air, the organoleptic score (ORS) and tongue-coating score (TCS) were measured before and after testing. Tonsillar microbiota were assessed by detection of periodontal pathogens, and profiling with terminal-restriction fragment length polymorphism (T-RFLP) analysis and sequencing of 16SrRNA clone libraries for taxonomic assignment. Gargling with BZC reduced the concentrations of methyl mercaptan and hydrogen sulfide and the ORS, but did not affect the TCS or prevalence of periodontal pathogens. T-RFLP analyses and 16SrRNA clone sequencing showed a tendency for some candidate species to decrease in the test group. Although gargling of the oropharyngeal area with an antiseptic agent can reduce oral malodor, it appears that tonsillar microbiota are not influenced greatly. (J Oral Sci 58, 83-91, 2016).

Probiotic consumption decreases the number of osteoclasts during orthodontic movement in mice

AIMS

The aim of the present study was to investigate the effect of probiotic (Bacillus Subtilis) supplementation on bone remodelling induced by mechanical loading.

METHODS

C57BL/6 mice were divided in two groups: (1) Probiotic and (2) Vehicle (water). The probiotic (1.5×10⁸CFU/mL) was administered orally for 14 days, starting two days before the induction of orthodontic tooth movement (OTM). OTM was determined by histomorphometric analysis by comparing the right to the left side of the maxilla. The number of osteoclasts was determined by counting TRAP-positive cells. Osteoblasts were counted on Masson's trichrome-stained slides.

RESULTS

OTM was similar between groups (with and without probiotic supplementation) (p=0.46). The number of TRAP-positive cells increased (p<0.01) on the experimental side (where the spring coil was installed) in comparison to the control side in both groups. However, the number of osteoclasts decreased (p˂0.01) in the probiotic group, in comparison to the vehicle group. There was an increase in the number of osteoblasts (p˂0.05) in both the Vehicle and Probiotic groups on the side under OTM, independent of probiotic supplementation.

CONCLUSION

Oral Supplementation with a probiotic influenced the number of osteoclasts adjacent to the tooth root during orthodontic movement in mice.

Favourable effects of Bacillus subtilis and Bacillus licheniformis on experimental periodontitis in rats

OBJECTIVES

The purposes of this study were to evaluate, in rats: i) the effects of Bacillus species on the development of experimental periodontitis (EP) via microtomographic, immunological and hematological assays (Experiment 1-E1); ii) the effects of Bacillus species as adjuncts to scaling and root planing (SRP) for the treatment of EP via histomorphometric and immunohistochemical analyses (Experiment 2-E2).

METHODS

In E1, 24 rats were divided into groups C1 (control), PROB1, EP1 and EP-PROB1. In groups with EP, the mandibular first molar of each animal received a ligature for 14 days. In groups PROB1, animals received Bacillus species for 44 days, starting 30 days before EP induction in Group EP-PROB1. In E2, 24 rats were assigned to groups C2 (control), PROB2, EP-SRP2 and EP-SRP-PROB2. In groups with SRP, EP was induced as described in E1. The ligatures were removed after 14 days and SRP was performed. In groups PROB2, animals received Bacillus species for 15 days, starting after SRP in Group EP-SRP-PROB2.

RESULTS

In E1, Group EP1 presented bone loss (BL) and eosinophil numbers greater than Group EP-PROB1 (P<0.05). In Group EP-PROB1, the receptor activator of nuclear factor-kB ligand (RANKL)/osteoprotegerin (OPG) ratio was similar to that of groups without EP. In E2, Group EP-SRP-PROB2 presented fewer TRAP-positive osteoclasts, lower immunolabeling pattern for a proinflammatory cytokine and decreased BL and attachment loss than Group EP-SRP2 (P<0.05).

CONCLUSIONS

Bacillus species supplementation provided a protective effect against BL and enhanced the effects of SRP in the treatment of EP in rats.

Antibacterial activity of vinyl imidazole(vi) functionalized silica polymer nanocomposites (SBA/VI) against Gram negative and Gram positive bacteria

Vinyl imidazole functionalized mesoporous silica (SBA/VI) nanocomposites for antibacterial activity.

Probiotics: can they be used to improve oral health?

The role of probiotic bacteria in improving human health has been an attractive subject for researchers since the beginning of the 20(th) century. They have been used to control gastro-intestinal infections, to promote immunity and to prevent various diseases (allergies, urogenital infections, etc.). However, the use of beneficial bacteria in the field of dentistry has only recently gained interest. Investigation of the effects of probiotic bacteria on oral health has become an important research subject. These studies are still in the early stages, however results show that probiotic bacteria are effective against tooth caries, periodontal disease, oral mucosal lesions and oral malodour. This review provides information on the effects of probiotics--well-known for their effects on general health, and therefore more widely used in healthcare--on oral and dental health, in order to promote their use/prescription by physicians and patients.

Effect of the probiotic Saccharomyces cerevisiae on ligature-induced periodontitis in rats

BACKGROUND AND OBJECTIVE

This study assessed the effects of the local use of Saccharomyces cerevisiae as monotherapy and as an adjuvant to the mechanical treatment of ligature-induced periodontitis in rats.

MATERIAL AND METHODS

Periodontitis was induced in 72 rats via the installation of a ligature around the mandibular first molar. After 7 d, the ligature was removed and the rats were placed in one of the following groups: no treatment (C; n = 18); scaling and root planing (SRP; n = 18); local irrigation with probiotics (PRO; n = 18); and SRP followed by local irrigation with probiotics (SRP/PRO; n = 18). Six rats from each group were killed at 7, 15 and 30 d. The histological characteristics, alveolar bone loss (ABL) and immunolabeling of tumor necrosis factor alpha (TNF-α), interleukin-1beta (IL-1β), interleukin-10 (IL-10) and TRAP on the furcation area of the first molar were assessed.

RESULTS

The PRO group showed features of acceleration of the tissue-repair process during the entire experiment. On day 15, there was less ABL in the SRP/PRO group compared with the C group. There were fewer TRAP-positive cells in the SRP and SRP/PRO groups at 30 d. There was less immunostaining for TNF-α in the PRO and SRP/PRO groups and less immunostaining for IL-1β in the PRO group. However, there was more immunostaining for IL-10 in the PRO group on day 15.

CONCLUSION

Local use of the probiotic did not result in any adverse effects on periodontal tissues. When used as monotherapy or as an adjuvant, the probiotic was effective at controlling periodontitis in rats.

Probiotics to counteract biofilm-associated infections: promising and conflicting data

Altered bowel flora is currently thought to play a role in a variety of disease conditions, and the use of Bifidobacterium spp. and Lactobacillus spp. as probiotics has been demonstrated to be health-promoting, even if the success of their administration depends on the applied bacterial strain(s) and the targeted disease. In the last few decades, specific probiotics have been shown to be effective in the treatment or the prevention of acute viral gastroenteritis, pediatric post-antibiotic-associated diarrhea, some pediatric allergic disorders, necrotizing enterocolitis in preterm infants, inflammatory bowel diseases and postsurgical pouchitis. The potential application of probiotics is continuously widening, with new evidence accumulating to support their effect on the prevention and treatment of other disease conditions, including several oral diseases, such as dental caries, periodontal diseases and oral malodor, as well as genitourinary and wound infections. Considering the increasingly widespread ability of pathogens to generate persistent biofilm-related infections, an even more attractive proposal is to administer probiotics to prevent or counteract biofilm development. The response of biofilm-based oral, intestinal, vaginal and wound infections to probiotics treatment will be reviewed here in light of the most recent results obtained in this field.

The numerous microbial species in oral biofilms: how could antibacterial therapy be effective?

Hundreds of bacterial species inhabit the oral cavity. Many of these have never been cultivated and can be assessed only with DNA-based techniques. This new understanding has changed the paradigm of the etiology of oral disease from that associated with 'traditional pathogens' as being primarily responsible for all diseases. Increasingly, associations between oral bacteria and systemic diseases are being reported. The emergence of antibiotic resistance is alarming and calls for in-depth studies of biofilms, bacterial physiology, and a body-wide approach to infectious diseases. We propose that the borderline between commensal bacteria and pathogens is no longer discrete. In a field of science where so many of the established paradigms are being undermined, a thorough analysis of threats and opportunities is required. This article addresses some of the questions that can be raised and serves to identify research opportunities and needs to leverage the prevention of oral diseases through novel antimicrobial strategies.

Evaluation of the effect of probiotic (inersan®) alone, combination of probiotic with doxycycline and doxycycline alone on aggressive periodontitis - a clinical and microbiological study

INTRODUCTION

The purpose of the present study was to evaluate the effect of a probiotic (Inersan®) alone, a combination of the probiotic with doxycycline and doxycycline alone on aggressive periodontitis patients.

METHODS

Thirty patients who satisfied the inclusion and exclusion criteria, were assigned to one of the above mentioned three groups by using block randomization. The clinical and the microbiological parameters were recorded on day 0, at 2 weeks and at 2 months. On day 0, before recording the clinical parameters, 0.5 ml of unstimulated saliva was collected for the evaluation of the microbiological parameters. The clinical parameters which were recorded were the plaque index, the gingival index, the probing pocket depth and the clinical attachment level. The microbiological parameters which were recorded were Lactobacilli and Aggregatibacter actinomycetemcomitans. After this, Scaling and Root Planing (SRP) was performed on day 0. Two weeks after the SRP, the patients were recalled for the saliva sample collection and for the evaluation of the clinical parameters. On the same day, medications were given to the patients to be taken for fourteen days according to the group which they belonged to (Group A - probiotic alone, Group B - a combination of the probiotic with doxycycline, Group C - doxycycline alone). The patients were then recalled at two months for the saliva sample collection and for the evaluation of the clinical parameters.

RESULTS

The administration of the probiotic alone, a combination of the probiotic with doxycycline and doxycycline alone, resulted in a decrease in the plaque index, the gingival index, the probing pocket depth and the clinical attachment level at 2 months, which was statistically significant (p < 0.05). The A. actinomycetemcomitans count tended to decrease in all the three groups at 2 months, which was statistically non-significant (p > 0.05). The Lactobacilli count tended to increase significantly in the probiotic alone group (p < 0.05).

CONCLUSION

Probiotics have a future in the treatment of aggressive periodontitis, as antibiotics are prescribed most of the time. These antibiotics can lead to the emergence of drug resistant micro-organisms and they can also disturb the beneficial microflora of the body. Thus, as an alternative to antibiotics, probiotics can be used, as they repopulate the beneficial microflora and reduce the pathogenic bacteria.

Probiotic therapy reduces periodontal tissue destruction and improves the intestinal morphology in rats with ligature-induced periodontitis

BACKGROUND

With increase in the incidence of resistance to antibiotics, probiotics are emerging as a promising adjunctive periodontal therapy. The authors of this study evaluate the influence of probiotic (PROB) supplementation on ligature-induced periodontitis (LIP) and intestinal morphology in rats.

METHODS

Thirty-two rats were randomly divided into four groups: control (C), LIP, PROB, and LIP/PROB. In groups PROB and LIP/PROB, the PROB was administered orally by addition to the drinking water of the animals for 44 days. In groups LIP and LIP/PROB, the mandibular right first molar of the animals received a cotton ligature that was left in the same position for 14 days. All animals were euthanized 44 days after the start of the PROB supplementation. The jaws were resected and histomorphometric analyses were performed. The measurements included evaluation of attachment loss (AL) and alveolar bone level (ABL) on the distal root of the mandibular first molar. Samples of the duodenum, jejunum, and ileum were also dissected from each animal to evaluate the villous height (VH) and crypt depth (CD). The data obtained were subjected to statistical analyses (analysis of variance, Tukey; P <0.05).

RESULTS

Mean values of AL and ABL were significantly higher in group LIP compared with group LIP/PROB (AL: 3.05 ± 0.57 mm and 1.78 ± 0.63 mm, respectively; ABL: 4.21 ± 0.42 mm and 3.38 ± 0.17 mm, respectively). In group LIP/PROB, the mean values of VH and CD of the jejunum were significantly higher than the ones from group LIP (VH: 672.1 ± 83.3 µm and 528.0 ± 51.7 µm, respectively; CD: 463.8 ± 100.9 µm and 269.0 ± 48.4 µm, respectively).

CONCLUSIONS

It can be concluded that PROB supplementation 1) reduces AL and alveolar bone loss in rats with LIP and 2) can protect the small intestine from reactive changes induced by LIP.

Mechanism of HERG potassium channel inhibition by tetra-n-octylammonium bromide and benzethonium chloride

Tetra-n-octylammonium bromide and benzethonium chloride are synthetic quaternary ammonium salts that are widely used in hospitals and industries for the disinfection and surface treatment and as the preservative agent. Recently, the activities of HERG channel inhibition by these compounds have been found to have potential risks to induce the long QT syndrome and cardiac arrhythmia, although the mechanism of action is still elusive. This study was conducted to investigate the mechanism of HERG channel inhibition by these compounds by using whole-cell patch clamp experiments in a CHO cell line stably expressing HERG channels. Tetra-n-octylammonium bromide and benzethonium chloride exhibited concentration-dependent inhibitions of HERG channel currents with IC(50) values of 4nM and 17nM, respectively, which were also voltage-dependent and use-dependent. Both compounds shifted the channel activation I-V curves in a hyperpolarized direction for 10-15mV and accelerated channel activation and inactivation processes by 2-fold. In addition, tetra-n-octylammonium bromide shifted the inactivation I-V curve in a hyperpolarized direction for 24.4mV and slowed the rate of channel deactivation by 2-fold, whereas benzethonium chloride did not. The results indicate that tetra-n-octylammonium bromide and benzethonium chloride are open-channel blockers that inhibit HERG channels in the voltage-dependent, use-dependent and state-dependent manners.

Probiotics as oral health biotherapeutics

INTRODUCTION

Oral health is affected by its resident microorganisms. Three prominent oral disorders are dental caries, gingivitis and periodontitis, with the oral microbiota playing a key role in the initiation/progression of all three. Understanding the microbiota and the diseases they may cause is critical to the development of new therapeutics. This review is focused on probiotics for the prevention and/or treatment of oral diseases.

AREAS COVERED

This review describes the oral ecosystem and its correlation with oral health/disease. The pathogenesis and current prevention/treatment strategies of periodontal diseases (PD) and dental caries (DC) are depicted. An introduction of probiotics is followed by an analysis of their role in PD and DC, and their potential role(s) in oral health. Finally, a discussion ensues on the future research directions and limitations of probiotics for oral health.

EXPERT OPINION

An effective oral probiotic formulation should contribute to the prevention/treatment of microbial diseases of the oral cavity. Understanding the oral microbiota's role in oral disease is important for the development of a therapeutic to prevent/treat dental diseases. However, investigations into clinical efficacy, delivery/dose optimization, mechanism(s) of action and other related parameters are yet to be fully explored. Keeping this in mind, investigations into oral probiotic therapies are proving promising.

Isolation and characterization of probiotic strains for improving oral health

Probiotics have been proven effective for preventing caries. In contrast, the effect of probiotics on improving oral diseases such as gingivitis, periodontitis and halitosis has been less explored.

OBJECTIVE

To perform a screening of lactic acid bacteria, according to international guidelines for the evaluation of probiotics, in order to select candidate probiotic strains for preventing oral disorders.

STUDY DESIGN

The strains were isolated from healthy children and were subjected to a variety of in vitro tests in order to show their functionality. The safety of the strains was assessed by determining antibiotic susceptibility and production of lactic acid.

RESULTS

Forty-six of the 100 new isolates were assigned to lactic acid bacteria genera after a biochemical characterization. Most of the new isolated strains seem to be resistant to oral conditions, have great ability to form aggregates and have high antagonistic activity against oral pathogens. None of the strains produced unpleasant volatile compounds. The strains showed high ability to adhere to oral tissues and they do not present any antibiotic resistance. Moreover, an increased risk of developing caries due to their ability to produce lactic acid was discarded in seven pre-selected probiotic candidates.

CONCLUSIONS

These lactic acid bacteria show promising properties to be used as potential probiotics for improving oral health.

Stimulation of suicidal erythrocyte death by benzethonium

Benzethonium, an antimicrobial surfactant widely used as preservative of pharmaceuticals, topical wound care product and oral disinfectant, triggers apoptosis of several cell types. The apoptosis is preceded and possibly triggered by mitochondrial depolarization. Even though lacking mitochondria, erythrocytes may similarly undergo suicidal cell death or eryptosis. Hallmarks of eryptosis include cell shrinkage and cell membrane scrambling with phosphatidylserine exposure at the cell surface. Eryptosis may be triggered by energy depletion, which leads to increase of cytosolic Ca(2+)-activity with subsequent Ca(2+)-sensitive cell shrinkage and cell membrane scrambling. Ca(2+)-sensitivity is enhanced by ceramide. The present study explored the effect of benzethonium on eryptosis. Cell membrane scrambling was estimated from binding of fluorescent annexin V to phosphatidylserine, cell volume from forward scatter in FACS analysis, cytosolic Ca(2+)-concentration from Fluo3-fluorescence, hemolysis from hemoglobin release, lactate formation by colorimetry and ceramide utilizing fluorescent antibodies. A 48 hours exposure to benzethonium (=5μM) significantly increased cytosolic Ca(2+)-concentration, decreased forward scatter and triggered annexin V-binding affecting some 30% of the erythrocytes at 5 μM benzethonium. Only 5% of treated erythrocytes were hemolytic. The effects of benzethonium on annexin V binding were blunted in the nominal absence of Ca(2+) and in the presence of amiloride (1 mM) but not in the presence of the pancaspase inhibitor zVAD (10 μM). Benzethonium further significantly enhanced the effect of glucose depletion on cytosolic Ca(2+)-concentration and annexin V-binding, but significantly blunted the effect of glucose depletion on forward scatter. Benzethonium (5 μM) significantly enhanced lactic acid formation but not ceramide abundance. The present observations disclose a novel effect of benzethonium, i.e. triggering of suicidal death of erythrocytes.

Microbial competition between Bacillus subtilis and Staphylococcus aureus monitored by imaging mass spectrometry

Microbial competition exists in the general environment, such as soil or aquatic habitats, upon or within unicellular or multicellular eukaryotic life forms. The molecular actions that govern microbial competition, leading to niche establishment and microbial monopolization, remain undetermined. The emerging technology of imaging mass spectrometry (IMS) enabled the observation that there is directionality in the metabolic output of the organism Bacillus subtilis when co-cultured with Staphylococcus aureus. The directionally released antibiotic alters S. aureus virulence factor production and colonization. Therefore, IMS provides insight into the largely hidden nature of competitive microbial encounters and niche establishment, and provides a paradigm for future antibiotic discovery.

Do probiotics offer opportunities to manipulate the periodontal oral microbiota?

BACKGROUND

As in other fields of healthcare, probiotics have been introduced for prevention and treatment of periodontal diseases.

OBJECTIVE

This review was initiated to explore whether the use of probiotics can influence the periodontal microbiota and periodontal health.

MATERIALS AND METHODS

Literature on the mode of action of oral probiotics was reviewed and a systematic review was performed on the microbiological and clinical effects of oral probiotics on periodontal health.

RESULTS

Three animal and 11 in vivo human studies were retrieved. Six studies reported on microbiological effects whereas eight studies report on clinical effects. Seven studies were performed on healthy or gingivitis patients and four studies on periodontitis patients. Many of the retrieved studies are pilot in nature and with low quality. The high degree of heterogeneity between studies hampered analysis.

CONCLUSION

Taking into consideration all limitations, the currently available data indicate an effect of probiotics on the oral microbiota and a more limited effect on clinical periodontal outcome measures. However, there is an urgent need for properly conducted clinical trials where probiotics are used as adjuncts to standard periodontal care, similar to antibiotics, using probiotic strains with, at least at an in vitro level, proven periodontal probiotic effects.

Bovine milk fermented with Lactobacillus rhamnosus L8020 decreases the oral carriage of mutans streptococci and the burden of periodontal pathogens

AIM

  The aim of this study was to find the oral isolate of lactobacilli, which has the potential to inhibit either periodontal, cariogenic, or fungal pathogens in vitro, and to examine the effects of bovine milk fermented with the isolate on the oral carriage of cariogenic and periodontal pathogens.

METHODS

  The inhibitory effects of the supernatant of Man-Rogosa-Sharpe broth, in which each of 42 oral isolates of lactobacilli grown, was examined. One isolate, Lactobacillus rhamnosus L8020, that showed the potential to inhibit either periodontal, cariogenic, or fungal pathogens in vitro, was used to examine the effects of fermented milk on the oral carriage of cariogenic and periodontal pathogens, which was examined by a placebo-controlled and cohort trial using 50 participants.

RESULTS

  Edible yogurt containing Lactobacillus rhamnosus L8020 significantly reduced the oral carriage of mutans streptococci (P < 0.01) and four periodontal pathogens examined: Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Fusobacterium spp. (P < 0.01), but the phenomenon were not observed with the placebo yogurt (P > 0.05).

CONCLUSION

  These results suggest that yogurt with Lactobacillus rhamnosus L8020 could reduce the risk of dental caries and periodontal disease.