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Probiotics: Review of Literature

Nangia T, Setia V, Kochhar GK, Kaur K, Bansal R, Sharma R. Probiotics: Review Of Literature. J Periodontal Med Clin Pract 2014; 01:144-151

1 2 3 3 4 5Dr. Tanu Nangia , Dr. Vikas Setia , Dr. Gulsheen Kaur Kochhar , Dr. Kamaljit Kaur , Dr. Rupinder Bansal , Dr. Rahul Sharma

Review Article

Journal of Periodontal Journal of Periodontal

Medicine & Clinical PracticeMedicine & Clinical Practice

Journal of Periodontal

Medicine & Clinical PracticeJPMCPJPMCPJPMCPJournal of Periodontal Medicine

& Clinical Practice

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Affiliation:1. Assistant Professor, Department. Of Pedodontics & Preventive Dentistry,

Maharana Pratap College of Dentistry, Gwalior, MP,India2. Assistant Professor , Department Of Pedodontics & Preventive Dentistry

Adesh Institute of Dental sciences & Research, Bhatinda, Punjab, India3. Assistant Professor, Department Of Pedodontics & Preventive Dentistry

Swami Devi Dayal Hospital & Dental College, Barwala, Haryana, India4. Senior Lecturer, Department of Oral & Maxillofacial Surgery,

Adesh Institute of Dental sciences & Research ,Bhatinda, Punjab, India5. Assistant Professor, Department of Oral & Maxillofacial surgery,

Adesh Institute of Dental sciences & Research ,Bhatinda, Punjab, India�

Corresponding Author:Dr. Tanu NangiaAssistant Professor Department of Pedodontics & Preventive DentistryMaharana Pratap College of DentistryGwalior, MP, IndiaE-mail: [email protected]

ABSTRACT

For some decades now, bacteria known as probiotics

have been added to various foods because of their

beneficial effects for human health. The number of

products containing probiotics, viable bacteria with

proven health benefits, entering the market is

increasing. Traditionally, probiotics have been

associated with gut health, and most clinical interest has

been focused on their use for prevention or treatment of

gastrointestinal infections and diseases; however,

during the last decade several investigators have also

suggested the use of probiotics for oral health purposes

Although only a few clinical studies have been

conducted so far, the results to date suggest that

probiotics could be useful in preventing and treating

oral infections, including dental caries, periodontal

disease and halitosis. This article summarizes the

currently available data on the potential benefits of

probiotics for oral health.

Keywords ; probiotics, oral health, periodontitis.

INTRODUCTION

The belief that probiotic bacteria can influence health th

dates back to the beginning of the 20 century when the

Ukrainian-born Nobel Prize laureate Elie Metchnikoff

reported that Bulgarians lived longer than other

populations and supposed that this was due to their

consumption of fermented milk products containing [1]

viable bacteria. The idea was that the harmless bacteria

in the fermented products competed with pathogenes [1]

injurious to health. By definition, probiotics are live

microbial feed supplement that beneficially affects the

host animal by improving its intestinal microbial [2]

balance as documented in clinical trial. These bacteria

Vol- I, Issue - 2, May - Aug 2014

144

must belong to the natural flora in order to survive the

acid environment during transit to the intestines.

Probiotic bacteria can act through several paths: they

prevent cellular adhesion and invasion of pathogenic

bacteria, modify the intestinal environment by a

reduction in pH as a result of fermentation products and

they interact and modulate the local and systemic [3,4]

inflammatory immune response.

For several decades now, bacteria called probiotics have

been added to some foods because of their beneficial

effects for human health. The bacteria in yogourt and

fermented milk products constitute the most important

source of probiotics for humans. The vast majority of

probiotic bacteria belong to the genera Lactobacillus,

Bifidobacterium, Propionibacterium and Streptococcus.

Several clinical studies have already demonstrated the

effectiveness of certain probiotics in the treatment of [5]

systemic and infectious diseases. Probiotics may also

prove useful in addressing problems arising from the

excessive use of antibiotics, specifically the appearance

of bacterial resistance. To date, however, the potential

beneficial effects of probiotics for oral pathology have

had only limited study.

The most commonly used probiotic bacterial strains

b e l o n g t o t h e g e n e r a L a c t o b a c i l l u s a n d [6]Bifidobacterium. These bacterial genera are regarded

as a part of the normal human microbiota. In the oral

cavity, lactobacilli usually comprise fewer than 1% of

the total cultivable microbiota, but no species specific to

the oral cavity has been found. Species commonly

isolated from saliva samples include L. paracasei, L. [7]plantarum, L. rhamnosus, and L. salivarius. Culture-

based studies suggest that bifidobacteria are among the [8]first anaerobes in the oral cavity. Indeed, both

lactobacilli and bifidobacteria can be found in breast

milk, suggesting early exposure of the oral cavity to

[9,10]these bacteria. Bifidobacterial species isolated from

oral samples include B. bifidum, B. dentium, and B. [11,12]

longum.

Lactobacilli and bifidobacteria are generally regarded as [1]safe, and, since the early writing of Metchnikoff even

more fermented food products have been associated

with health benefits. In respect to normal microbiota and

oral health, there seem to be differences in the ability of

lactobacilli isolated from caries-active or healthy [13]subjects to inhibit Streptococcus mutans in vitro. In

addition, the species composition of both Lactobacillus

and Bifidobacterium microbiota is different between

patients with periodontitis and those who are [14,15]periodontally healthy. On the other hand, both

lactobacilli and bifidobacteria are also associated with [16,17]dental caries. In addition, caries-associated

lactobacilli and bifidobacteria have been characterized

as exogenous and opportunistic colonizers possibly [18]acquired from food.

Several clinical studies have already demonstrated the

effectiveness of certain probiotics in the treatment of

systemic and infectious diseases such as acute diarrhea [5]

and Crohn disease. Other studies have suggested

potential applications in the treatment of cardiovascular

disease, urogenital infections, oropharyngeal infections [19,20]

and cancers.

Mechanism of Action

Several mechanisms have been proposed to explain how

probiotics work. For example, these bacteria secrete

various antimicrobial substances such as organic acids, [21]

hydrogen peroxide and bacteriocins. In addition, they

compete with pathogenic agents for adhesion sites on [22,23]

the mucosa. Probiotics can also modify the

surrounding environment by modulating the pH and/or

the oxidation–reduction potential, which may

compromise the ability of pathogens to become





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Probiotics: Review of LiteratureVol- I, Issue - 2, May - Aug 2014

145

established. Finally, probiotics may provide beneficial effects by stimulating nonspecific immunity and modulating the [24]

humoral and cellular immune response. A combination of probiotic strains is often used to increase these beneficial

Fig.1 Mechanism of action of probiotics

PROBIOTICS AND ORAL HEALTH

Probiotics and Dental Caries

Dental caries is a multifactorial disease of bacterial

origin that is characterized by acid demineralization of [26]

the tooth enamel. It appears following changes in the

homeostasis of the oral ecosystem leading to

proliferation of the bacterial biofilm, composed notably

of streptococci from the mutans group. To have a

beneficial effect in limiting or preventing dental caries, a

probiotic must be able to adhere to dental surfaces and

integrate into the bacterial communities making up the

dental biofilm. It must also compete with and antagonize

the cariogenic bacteria and thus prevent their

proliferation.

Finally, metabolism of food-grade sugars by the

probiotic should result in low acid production. The

advantage of incorporating probiotics into dairy

products lies in their capacity to neutralize acidic

conditions. It has already been reported that cheese

prevents demineralization of the enamel and promotes [27,28]

its remineralization. Comelli and colleagues reported

that of 23 bacterial strains used in the dairy industry,

Streptococcus thermophilus and Lactobacillus lactis ssp.

lactis were the only ones with the capacity to integrate

into a biofilm present on a hydroxyapatite surface and to

interfere with development of the cariogenic species

Streptococcus sobrinus. More recently, it was

demonstrated that isolates of W cibaria had the capacity

to inhibit, both in vitro and in vivo, biofilm formation by

S mutans and to prevent proliferation of this bacterial [29] [30]

strains. Recently, Petti and colleagues reported that

yogourt containing S thermophilus and L bulgaricus had





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selective bactericidal effects on streptococci of the

mutans group. Several clinical studies have

demonstrated that regular consumption of yogourt,

milk or cheese containing probiotics led to a decrease in

the number of cariogenic streptococci in the saliva and a [31,32,33]reduction in dental plaque. More specifically,

[33]Nikawa and colleagues reported that consumption of

yogourt containing Lactobacillus reuteri over a period

of 2 weeks reduced the concentration of S. mutans in

the saliva by up to 80%. Comparable results were

obtained by incorporating probiotics into chewing gum [32,34] [35]or lozenges. In 2001, Nase and colleagues

published the results of a long-term (7-month) study of

594 children 1 to 6 years of age that evaluated the

effects on dental caries of consuming milk

supplemented with a strain of L rhamnosus. The authors

concluded that children consuming milk containing this

probiotic, particularly those 3–4 years of age, had

significantly fewer dental caries and lower salivary

counts of S. mutans than controls. These promising

results suggest a potentially beneficial application of

probiotics for the prevention of dental caries.

Periodontal diseases

The first studies of the use of probiotics for enhancing

oral health were for the treatment of periodontal [36]inflammation. Patients with various periodontal

diseases, gingivitis, periodontitis, and pregnancy

gingivitis, were locally treated with a culture

supernatant of a L acidophilus strain. Significant

recovery was reported for almost every patient. There

has been significant interest in using probiotics in

treatment of periodontal disease recently, too. The

probiotic strains used in these studies include L reuteri

strains, L brevis (CD2), L casei Shirota, L salivarius

WB21, and Bacillus subtilis. L. reuteri and L. brevis

have improved gingival health, as measured by [37,38,39]decreased gum bleeding.

The use of probiotic chewing gum containing L. reuteri

ATCC 55730 and ATCC PTA 5289 also decreased [39]levels of pro-inflammatory cytokines in GCF and the

use of L. brevis decreased MMP (collagenase) activity [38]and other inflammatory markers in saliva.

B. subtilis seemed to reduce the number of periodontal [40]

pathogens. Use of tablets containing L. salivarius

WB21 has been shown to decrease gingival pocket

depth, particularly in high-risk groups such as smokers,

and also affect the number of periodontopathogens in [41,42]

plaque. Again, although encouraging results have

been observed, most studies have been fairly short.

Furthermore, in some studies the observed differences

were quite small, though statistically significant.

Oral candida

Two studies have investigated the effects of probiotic [43,44]

bacteria on oral Candida infection in humans.

When a test group of elderly people consumed cheese

containing L. rhamnosus strains GG and LC705 and

Propionibacterium freudenreichii ssp. shermanii JS for

16 weeks, the number of high oral yeast counts

decreased, but no changes were observed in mucosal [44]

lesions. In a shorter study with younger subjects, no

significant difference was observed between effects of

probiotic and those of control cheese on salivary [43]

Candida counts.

Halitosis

Halitosis has many causes (including consumption of

particular foods, metabolic disorders, respiratory tract

infections), but in most cases it is associated with an

imbalance of the commensal microflora of the oral [45]cavity. More specifically, halitosis results from the

action of anaerobic bacteria that degrade salivary and

food proteins to generate amino acids, which are in turn

transformed into volatile sulphur compounds, [45]including hydrogen sulphide and methanethiol. Kang

[46]and colleagues reported the capacity of various

strains of W cibaria to inhibit the production of volatile





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sulphur compounds by F nucleatum. They concluded

that this beneficial effect resulted from the production of

hydrogen peroxide by W cibaria, which inhibited the [46] [47]proliferation of F nucleatum. A recent study

showed that certain bacterial species, including

Atopobium parvulum , Eubacterium sulci and

Solobacterium moorei, predominate on the dorsal

surface of the tongue among people with halitosis.

Conversely, another species, Streptococcus salivarius,

was detected most frequently among people without

halitosis and is therefore considered a commensal [47]probiotic of the oral cavity. S salivarius is known to

produce bacteriocins, which could contribute to

reducing the number bacteria that produce volatile [48]sulphur compounds. The use of gum or lozenges

containing S salivarius K12 (BLIS Technologies Ltd.,

Dunedin, New Zealand) reduced levels of volatile

sulphur compounds among patients diagnosed with [49,50]halitosis.

CONCLUSION

Bacteriotherapy in the form of probiotics seems to be a

natural way to maintain health and protect oral tissues

from disease, and data suggest that the potential benefits

increase with an early childhood start. The research is

still in its infancy but a daily intake of probiotic

lactobacilli with an inhibitory effect on other bacteria is

currently most promising. Milk, milk drinks, or yoghurt

containing one or more probiotic strains could be a

treatment option in the long-term prevention of

childhood caries. However, further double-blind,

randomized, placebo-controlled trials that assess

carefully selected and defined strains of probiotics using

standardized outcomes are needed before any clinical

recommendations can be made.

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Competing interest / Conflict of interest The author(s) have no competing interests for financial support, publication of this research, patents and royalties through this collaborative research. All authors were equally involved in discussed research work. There is no financial conflict with the subject matter discussed in the manuscript. Source of support: NIL

Copyright © 2014 JPMCP. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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