Assessment of knowledge and awareness of probiotics among the dental post-graduate students- A questionnaire study

Mahendra R Patait; Kedar V Saraf; Priya M Wakchaure

doi:10.4103/0019-5049.340742

ORIGINAL ARTICLE

Year : 2022 | Volume : 34 | Issue : 1 | Page : 68-75

Assessment of knowledge and awareness of probiotics among the dental post-graduate students- A questionnaire study

Mahendra R Patait, Kedar V Saraf, Priya M Wakchaure
Department of Oral Medicine and Radiology, S. M. B. T. Dental College, Hospital and Post-graduate Research Center, Amrutnagar- 422 608, Sangamner, Ahmednagar, Maharashtra, India

Date of Submission	19-Aug-2021
Date of Acceptance	13-Jan-2022
Date of Web Publication	25-Mar-2022

Correspondence Address:
Dr. Priya M Wakchaure
'Priti' Bunglow, Agasti Vihar, Near Balaji Nagar, Ghulewadi, Sangamner - 422 605, Ahmednagar, Maharashtra
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/0019-5049.340742

Abstract

Background: Probiotics are viable microorganisms, and when they are administered in an adequate amount, they provide health benefits to the host. The use of probiotics is said to be an important aspect in dentistry in the prevention and treatment of caries, periodontal disease, etc. Aims: The purpose of the present research was to access knowledge and awareness of probiotics among dental postgraduate students. Settings and Design: A total of 104 dental postgraduate respondents from Maharashtra state were surveyed regarding the knowledge of probiotics.The study includes first, second, and third-year dental postgraduate students. A well-structured and administered questionnaire including 15 questions was used to elicit the responses from the dental postgraduate students.Methods and Material: The online survey was distributed via email and social media platforms using snowball sampling and was open for a week. The questions were modeled based on those used in previously published studies on the knowledge of probiotics. The questionnaire consisted of 15 questions. The survey took less than 15 minutes on average to complete.Statistical Analysis Used: Data entries were done in Microsoft Office Excel 2010, and analyses of results were done using Statistical product and service solution (SPSS) version 21 software. Descriptive statistics such as frequencies and percentage/proportion were calculated. Pearson Chi-square test was used to find out the difference between responses of study subjects.Results: Of the 104 postgraduate students in total, 68.3% of respondents were females, and 31.7% were males. The study reveals 98% of participants are aware of the term probiotics and 94.1% of respondents correctly answered that constituents of probiotics are live microorganisms. More than half of the respondents (52%) had taken probiotics as a therapeutic drug for gastrointestinal purposes. 76.5% of respondents thought it helps in the improvement of oral health.Conclusions: In the present study, a good level of knowledge was observed among dental postgraduate students. Most of them were aware of the beneficial effects of probiotics on the human body in terms of food digestion and immunity. However, they still lack the other health benefits of probiotics. Also, there was little less knowledge and clarity about the term prebiotic.

Keywords: Live microorganisms, oral health, probiotics

How to cite this article:
Patait MR, Saraf KV, Wakchaure PM. Assessment of knowledge and awareness of probiotics among the dental post-graduate students- A questionnaire study. J Indian Acad Oral Med Radiol 2022;34:68-75

How to cite this URL:
Patait MR, Saraf KV, Wakchaure PM. Assessment of knowledge and awareness of probiotics among the dental post-graduate students- A questionnaire study. J Indian Acad Oral Med Radiol [serial online] 2022 [cited 2022 May 27];34:68-75. Available from: https://www.jiaomr.in/text.asp?2022/34/1/68/340742

Introduction

The human oral cavity and gastrointestinal tract house multiple bacteria, which show a symbiotic relationship with the host. Important functions like immunity, harvesting energy, and lipid metabolism are performed by these bacteria. The development of commercial products like probiotics and prebiotics helped to modify gut bacteria which was found to be beneficial for the health of the host.^[1]

In food and nutritional science, probiotic is one of the intense and widespread subjects for research. Derived from Greek word, the term probiotics means life. In 1965, it was first used by Lily and Stillwell. They described the term as substances secreted by one microorganism which stimulate the growth of others.^[2]

In 2001, at an expert consultation of an international scientist working on behalf of the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO), the definition of probiotics was accepted. The International Scientific Association for Probiotics and Prebiotics (ISAPP) then published the most recent and widely accepted definition of probiotics in 2014. The definition was given as, live microorganism, when administered in adequate amount, confers the health benefits of the host.^[3]

In 1908, Élie Metchnikoff received the Nobel Prize in Medicine for his work with gut microbiota and immune system. Since 1935, Yakult (Yakult Honsha Co., Ltd) has been a Japanese dairy probiotic product in the market. A selectively fermented ingredient that allows specific changes in composition and/or activity in the gastrointestinal microflora that confers beneficial effects on host well-being and health, they are known as the prebiotics. They stimulate growth of beneficial bacteria that are already present in the gut.^[1]

There is widespread and easily accessible evidence that supports the benefits of probiotics in the prevention and treatment of irritable bowel syndrome, ulcerative colitis, travelers' diarrhea, and dental caries, periodontal and other oral diseases.^[2],[3] Therefore, the purpose of the present research was to access knowledge and awareness of probiotics among dental postgraduate students.

Material and Method

The online survey was distributed via email and social media platforms using snowball sampling and was open for a week. The questions were modeled based on those used in previously published studies on the knowledge of probiotics. The questionnaire consisted of 15 questions.

A total of 104 respondents were involved in the research by answering the online survey. The survey was anonymous and voluntary. The respondents were given the opportunity to add their email addresses if they wished to receive a copy of the results. Online informed consent was obtained from the participants before starting the study. Institutional ethical permission was obtained from the Committee on Ethics, SMBT Dental College, Sangamner (via certificate no SMBT/335-A/2021 dated 05/04/2021). The protocol was in compliance with ethical guidelines with consideration of the declaration of Helsinki Indian GCP and ICMR guidelines.

The survey was divided into three sections. The first section consisted of demographic questions about the respondents' personal information and knowledge of probiotics. In the second section, the respondents were first asked to evaluate their knowledge of probiotics and talk about the respondents' experience in the use of probiotics, their beliefs about the positive effects of probiotics, and whether they have ever advised the use of probiotics. In the third section, the respondents were asked about their major sources of information regarding overall health and oral health benefits of probiotics and if they would like to develop more extensive knowledge on probiotics and prebiotics. The survey took less than 15 minutes on average to complete.

Data entries were done in Microsoft Office Excel 2010, and analyses of results were done using Statistical product and service solution (SPSS) version 21 software. Descriptive statistics such as frequencies and percentage/proportion were calculated. Pearson Chi-square test was used to find out the difference between responses of study subjects. The P value was fixed at 0.05.

Sample size estimation formula:-

Result

One hundred and four postgraduate students responded to this questionnaire survey. Mean age ± S.D. of the respondents was 26.06 ± 1.5 years, ranging from 22 to 33 years. Of the 104 postgraduate students in total, 68.3% (n = 71) of respondents were females and 31.7% (n = 33) were males. 98.1% (n = 102) postgraduate students were aware about the term probiotics and 1.9% (n = 2) who had not heard the term probiotics were not included for the further study. [Figure 1] For the study analysis part, 102 respondents were considered.

Figure 1: Respondents' knowledge about the term probiotics; consumption of probiotics among respondents; and their knowledge regarding the prebiotics and probiotics

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From various sources including Doctors 44.1% (n = 45), Social media 12.7% (n = 13), and Internet 43.1% (n = 44) respondents had acquired their knowledge of probiotics.(x²=19.471P < 0.001). Respondents were asked to mark the constituents of probiotics from; (1) Live microorganisms, (2) Synthetic drugs, (3) Natural plant products, (4) Chemicals in food, (5) Don't know. 94.1% (n = 96) respondents correctly answered that constituents of probiotics are live microorganisms. 2.9% (n = 3) and 2% (n = 2) of the respondents answered for natural plant products and chemicals in food respectively. None of the respondents selected for synthetic drugs. Only one (n = 1) of the respondents did not know about the constituents of probiotics.(x²=260.0 P < 0.001) [Figure 2].

Figure 2: Respondents' source of information about probiotics and knowledge related to constituents of probiotics

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67.6% (n = 69) respondents mentioned that probiotics were best consumed through food and drinks. 26.5% (n = 27) believed it was through supplements and 5.9% (n = 6) were unaware about this.(x²=60.529P < 0.001). Dairy products were considered as the most common source of dietary probiotic supplements. 94.1% (n = 96) of respondents believed that dairy products like milk and yogurt were sources of probiotics. 4.9% (n = 5) and 1% (n = 1) thought fruits and vegetables and cereals and pulses as the sources of probiotics respectively. None of the respondents thought of meat sources and sweets as the source.(x²= 169.8 P < 0.001)[Figure 3].

Figure 3: Respondents' awareness regarding better consumer products and the food sources of probiotics

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82.4% (n = 84) respondents reported personally having consumed food with probiotics and 17.6% (n = 18) had not consumed food with probiotics.(x²=42.7P < 0.001) [Figure 1] Out of 84 respondents who previously reported consumption of food with probiotics personally, 31% (n = 26) consumed it for once a day, 28.6% (n = 24) for 2–3 times/week, 20.2% (n = 17) weekly, 13.1% (n = 11) daily and 7.1% (n = 6) rarely consumed food with probiotics.(x²=31.876 P < 0.001). 68.6% (n = 70) respondents believed that consumption of probiotics can improve food digestion and 29.4% (n = 30) of respondents thought taking probiotics can increase immune health. Only 2% (n = 2) believed that probiotics were beneficial to decrease the risk of diabetes. None of the respondents selected probiotic is beneficial for to decrease the risk of hypertension.(x²=68.706P < 0.001).

More than half of the respondents 52% (n = 53) had taken probiotics as a therapeutic drug for the gastrointestinal purposes, 6.9% (n = 7) for oral health, 2% (n = 2) for cardiac and 1% (n = 1) for autoimmune conditions respectively. None of the respondents had taken it for the respiratory conditions. 38.2% (n = 39) had never taken probiotics as therapeutic drugs.(x²=112.9P < 0.001) [Figure 4] Considering the beneficial effects of consumption of probiotics; 76.5% (n = 78) of respondents thought it helps in the improvement of the oral health. Only1.9% (n = 2) thought it doesn't help to improve oral health. Whereas 21.6% (n = 22) did not know about it.(x²=91.294P < 0.001) [Figure 5].

Figure 4: Respondents' knowledge related to the conditions for using probiotics

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Figure 5: Respondents' awareness related to the role of probiotics in the improvement of oral health

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56.9% (n = 58) respondents believed that probiotic treatment consisting of L. salivaris improved both the factors of plaque index and probing depth in smokers. Whereas 24.5% (n = 25) and 6.9% (n = 7) respondents thought that only plaque index and probing depth were improved after probiotic treatment containing L. salivaris respectively. 11.8% (n = 12) thought it doesn't improve any of the factors mentioned before.(x²=62.0P < 0.001) In oral cavity, periodontal infections that are caused by pathogenic organisms disturbs the normal oral microbiome. This phenomenon is considered as dysbiosis. Probiotics helps to control this imbalance. Only 17.6% (n = 18) of the respondents considered this option. 40.2% (n = 43) were unaware about it.(x²=11.535P = 0.003). Respondents were asked about prebiotics and how do they differ from the term probiotics. 45.1% (n = 46) respondents were aware about it and 54.9% (n = 56) were unaware about the details.(x²=0.980P = 0.322) [Figure 1].

The respondents then had to choose from three different claims for the definition of prebiotics:

Specialized plant fiber that acts as a food for good bacteria
Stimulate growth among pre-existing good bacteria or
Both.

The correct option both was chosen by 52.1% (n = 24) of respondents. (x²=53.756P < 0.001) Considering the knowledge of combination of prebiotic and probiotic therapy; 37% (n = 17) choose multibiome therapy. 39.2% (n = 18) believed it as microbiome therapy and 23.8% (n = 11) considered both as a option. (x²=49.765P < 0.001) [Figure 6].

Figure 6: Respondents' knowledge regarding the term prebiotics and combination therapy of prebiotics and probiotics

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Discussion

The questionnaire given to the postgraduate students was simple and easy to understand. The present cross-sectional study is overall about the assessment of knowledge and awareness about the probiotics among the dental postgraduate students. A total of 104 postgraduate students responded to the questions. The mean age of respondents was 26.06 ± 1.5 years (S.D.), which ranges from 22 to 33 years. The majority of them were females (68.30%) with a female to male ratio of 2:1 approximately.

By definition, probiotics are viable microorganisms, and when they are administered in an adequate amount, they provide health benefits to the host.^[4]In the present study, 98.1% of the respondents had heard the term called probiotics, and those 1.9% who were unaware about the probiotics were excluded from the study. So for the further questionnaire, consideration to only 102 students was given out of a total of 104. Almost all the respondents (98.1%) knew what probiotics are. Most of the respondents obtained information from their doctors or healthcare practitioners (44.1%). This highlights the important role doctors or healthcare practitioners play in the dispersal of knowledge with regard to probiotics.

Respondents were then asked about the constituents of probiotics; About 94.1% of the dental postgraduate students correctly selected live microorganisms as their answer. Lactobascillus, Bifidobacterium, and Streptococcus strains are commonly used as probiotic bacteria which have more health benefits.^[5],[6]

In the present survey, most of the respondents believed that probiotic food was best consumed through food and drinks (67.6%), and only 26.5% believed it was through supplements.

We asked respondents about common sources of dietary probiotic products, and 94.1% thought products like milk and yogurt as a common source. In the study given by Philip C et-al. 33% of participants responded both as an option for milk and yogurt.^[2]Also, in the review by Kerry et-al., dietary products with nondairy fermented food products were also included as dietary probiotics.^[7] But only 44.51% selected for these, and the rest 88.74% selected dietary products.^[8]

82.4% of the respondents reported personally having consumed food with probiotics, and 17.6% had no history of probiotic food consumption. Then regarding the frequency of the consumption question was put forward. Out of 82.4% of the respondents who had previously reported consumption of food of probiotics personally, 31% consumed it once a day, 28.6% 2–3 times per week, 20.2% weekly, and 13.1% rarely. Forty percent of the respondents consumed probiotic food daily in the study given by Melanie Betz etal.^[1]

Also, 68.6% of the participants reported that consumption of probiotics can improve food digestion, and 29.4% thought taking probiotics can improve immune health. A study by Sabina Fijanet-al.^[3] states that respondents in their study advised probiotics to the patients for the reasons mainly diarrhea, constipation also for irritable bowel symptoms, ulcerative colitis, and in mothers and babies in families with allergic conditions. Also, 20% of the respondents equally believed in gastrointestinal and autoimmune conditions in a research done by Philip C et-al.^[2]

Regarding personal experience, when participants were asked about the consumption of probiotics as a therapeutic drug, 52% reported it was for gastrointestinal purpose, and 38.2% had never taken probiotics. A research by Melanie Betz et-al.,^[1] was done for the assessment of knowledge and use of probiotics and prebiotics in hospitalized patients, states consumption for overall conditions like digestion and gut health was 41% and 86% believed in the beneficial effects.

The ability of the probiotic bacteria is to strengthen the epithelial barrier function for interaction with oral epithelium. [Flowchart 1] summarizes the probable combined effects of probiotics on oral health.^[6]

Considering the present study 76.5% of respondents thought probiotics help in the improvement of the oral cavity.

A mixture of Streptococcal species with probiotic Lactobacillus brevis CD2 was applied as an adjuvant probiotics therapy; the results were seen like delayed re-colonization of pathogens which causes periodontitis, through the modulatory effects on the host response and periodontal microbiota it finally reduces the inflammation. Both the plaque index and probing depth were improved in smokers after probiotic therapy consisting of L. salivaris, according to Shi mauchi et-al.^[9] In the treatment of symptoms like probing depth, bleeding on probing, and gingival index, a combination of probiotics with salivary prostaglandins E₂, matrix metalloproteinase, and interferon-γ were found to be effective according to the research reports. Also, in the present study, 56.9% of respondents believed that both factors like plaque index and probing depth were improved in smokers with the probiotic treatment consisting of L. salivaris.

In the oral cavity, colonization of pathogenic organisms causes periodontal infections that disturb the balance of the normal oral microbiome. Dysbiosis is the term given for this imbalance.^[5] Lactic acid, hydrogen peroxide, bacteriocins are compounds produced by probiotics that help to reduce pathogenic bacteria biofilm and further reduce inflammatory factors like cytokines, PGE₂, collagenases, and elastases. In the present survey, only 17.6% selected the correct option. 42.2% considered this imbalance as symbiosis, where the broad term in biology stands for any of the several living arrangements between members of two different species, including mutualism.

A pathogenic process of dental caries is mainly initiated with the action of streptococcus mutuans. With the regular use of probiotics, there was found a substantial reduction in colony-forming units (CFUs) of S. mutuans. The most effective probiotic bacterium was Bifidobacterium for reducing S. mutuans (CFUs).^[5]

Periodontitis with the putrefactive activity of tongue microbiota produces volatile compounds in a condition called halitosis or oral malodor. Bacteriocin-producing strains S. salivarius K12, is the earliest probiotic strain that helps to target oral malodor. After treatment with a chlorhexidine rinse, this strain reduced breath volatile sulfur compounds (VSCs) concentrations who consumed probiotic lozenges.^[4]

Then in the present study, respondents were asked whether they know the term prebiotic and do they differ from probiotics. 45.1% of participants were aware of it. A selectively fermented ingredient that allows specific changes in composition and/or activity in the gastrointestinal microflora that confers benefits upon host well-being and health are known as prebiotics. Insulin and fructooligosaccharides (FSO) are the prebiotics fibers fermented in the intestine, which stimulate the growth of beneficial bacteria already present in the gut.^[1] Substrates that are selectively used by host microorganisms that confer health benefits are known as prebiotics.^[3]

In the present survey, 52.1% of respondents correctly selected for the option including both options, which states prebiotics are specialized plant fiber that act as a food for pre-existing good bacteria. Also, the non-viable microbial cells, microbial fractions, or cell lysates give physiological benefits to the host by providing additional bioactivity. This is known as paraprobiotics or postbiotics.^[3]

The dietary supplements or good ingredients that combine the effects of probiotics and prebiotics are the symbiotics.^[3]The combination for this therapy is microbiome therapy.^[10] 39.2% of the respondents chose the microbiome therapy as an option. Microbiome remedy reverses the oral mucosal dysbiosis to eubiosis, this is, conversion of pathogenic to symbiont microbiota community much like cariogenic micro organism and periodontal pathogens by using modulating host immune response.^[10]

The major opportunistic fungal pathogens like C. albicans, C. krusei, C. tropicalis, C. glabrata, C. parapsilosis, and C. dubliniensis can cause infectious candidiasis under suitable conditions.^[5]In oral candidial infections, L. rhamnosus GR-1, L. reuteri RC-14, and L. reuteri ATCC PTA 5289 probiotic shows inhibitory effects against C. albicans and L. reuteri strains. As an adjuvant to anticancer drugs, probiotics like L. rhamnosus strain GG (LGG) and Bifidobacterium adolescentis SPM0212 exhibit an antiproliferative role.^[5]

In various forms, probiotics can be formulated and marketed. As supplements to these formulations, prebiotics and vitamins can be added, which are designed for easy handling and storage. The minimal effective dose for a probiotic is between 106 and 109 CFUs per day. When the targeted site is in the GIT, the best form of delivery is through the oral route. Diluents, binder, lubricant, coating agent, and sweetening agent, a suppository base; such as microcrystalline cellulose, silicon dioxide, rice maltodextrin, hydroxypropyl methylcellulose, and magnesium stearate are added to upgrade the performance of the probiotics.^[5]

Selection of Probiotics-

The criteria for selecting a probiotic product should be:^[11]

They ought to be non toxic and non pathogenic training.
Produce beneficial impact
Should resist gastrointestinal juice
Should have proper shelf life
Should update and reinstate the intestinal microflora

Ideal requisites of a probiotic^[12]

There must be micro organism to compete for all of the 4 principal meals substances of carbohydrates, proteins, fat and fiber
There have to be micro organism to breakdown gases of sulfur, nitrogen and phosphorus
There should be antibiotic and bacteriocin manufacturers to hold the pathogens under manage
The very last element should be able to keep the unique species from competing towards each other
Finally, the probiotic product must be an antioxidant because oxidation is the purpose of stains, plaque and malodors.

Probiotics can create a biofilm, performing as a defensive lining for oral mucosa in opposition to oral sicknesses. Use of probiotics together with antibiotics, can lessen the results of the dysbiosis because of the antibiotics, and maximize the benefits on the gut by using immune stimulation. Probiotics will improve inflammation with the aid of exerting tremendous outcomes on the epithelial cells and mucosal immunity dysfunction that forms the premise of infection.^[13]

Limitations and Future Prospects

As this was an online survey, there were certain limitations of the study like poor response rate, difficulty in judging the seriousness of the responses, and the absence of potential participants lacking internet skills. Response bias was also considered to be one of the limiting factors, as the participants respond mandatorily and not voluntarily in such surveys, and this is religiously true when the students are involved. So, future studies can be conducted using one on one interview methods.

Conclusion

In the present study, a good level of knowledge was observed among dental postgraduate students. Most of them were aware of the beneficial effects of probiotics on the human body in terms of food digestion and immunity. Also, in general, they knew that dairy products were food sources of probiotics, and the majority of them used to consume probiotics once in a day. It was also revealed in the present study that despite the high level of knowledge and awareness on probiotics, the consumption of probiotic food products of the students was mainly for gastrointestinal conditions. However, they still lack the other health benefits of probiotics. Also, there was little less knowledge and clarity about the term prebiotic. Nutrition education and media campaign can be used as an intervention to address the correctness of information about prebiotic and probiotic products as well as to promote the increased awareness of probiotic consumption.

Declaration of participants consent

The authors certify that they have obtained all appropriate participants consent forms. In the form, the participants(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The participants understand that their names and initials will not be published, and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

“Assessment of Knowledge and Awareness of Probiotics Among the Dental Postgraduate Students-A Questionnaire Study”

Email address:

Age:

Gender:

Have you ever heard the term 'probiotic'?

If yes, then how did you obtain information about probiotics?

What do you think are the constituent of probiotics?

Consumption of probiotics is better from-

Identify the food source of probiotics-

Do you consume food products with probiotics?

If yes, what is the frequency of consumption?

Which of the following health benefits can be taken from consuming probiotics?

You have used probiotics as a therapeutic drug for which of the following conditions?

Do you think the consumption of probiotics helps to improve oral health?

In smokers, which of the following factors were improved after probiotic treatment consisting of L. salivaris?

Probiotics can control which of the following imbalance and thus reduce the chances of oral infection?

Are you aware of prebiotics, and how do they differ from probiotics?

Prebiotics are-

A combination of prebiotic and probiotic therapy is known as-

Microbiome therapy

Multibiome therapy

Both

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