In mid 2013, researchers in India conducted a randomized trial that looked at probiotic use and its oral health benefits in school children. This study, conducted on students between the ages of 14-17, showed a significant increase in plaque reduction by feeding the students a common dairy product called curd. Although these results have been shown before in various other studies, this study demonstrates a practical approach to dietary probiotics that may reduce the risk of cavities and gum disease (1).
This randomized double-blind placebo-controlled study was conducted on 208 healthy school children between the ages 14-17 years old. All students involved in the study were required to bring a permission slip to participate in the study. 104 students were selected randomly to Group A (probiotic group) and 104 students to Group B (non-probiotic group or control group). All subjects were encouraged to continue their normal oral hygiene practices and to brush twice a day in whatever method of brushing they were currently using. A gingival and plaque index was recorded both pre- and post-intervention. The mean difference between group A and group B for both indexes was calculated. All information was entered into a Microsoft excel sheet for statistical analysis through the SPSS statistical software. The most significant results found were in the plaque index scores. There was a reduction of .91 mean differences in plaque accumulation which was statistically significant (p<0.05) (1). There were also reductions in the gingival index score but were not found to be statistically significant. The results show that the dietary source of probiotics were in fact beneficial to plaque accumulation and there reduced risk of caries. The results in the gingival index were not significant but have been shown to be significant in other studies.
The simplicity of this study is evident. This simplistic characteristic is both a strength and limitation. Its strength comes from the easy and straightforward method by which they measured the performance of probiotic use, namely the gingival index and plaque index. However, I believe it is simply confirming what others have already shown (2,3,4). What the study failed to do was provide new information to the problems it cites. The researchers had the perfect opportunity to measure and provide results for oral hygiene after the administration of probiotics. This could have helped provide information on whether probiotics may be a short-term fix or a more viable solution to more serious periodontal diseases. They provide little insight into their results or even mention the fact that the control group (no probiotic use) showed results. In conjunction with this, it would be interesting to know how brushing and flossing increased or decreased in the individuals during the study. Lastly, the conclusion includes a claim that may be questionable. The researchers suggest, “if the [dietary probiotic product] is promoted in the regular diet it would help in improving the oral health.” This claim may be misleading. To many, this could suggest an improvement without brushing or flossing. Also, what does it mean to improve oral health? Should it be used for all individuals regardless of their current oral health status? Or should it be used as treatment for those with carious legions and other oral cavity symptoms? The weaknesses of this study are two-fold. First, the study is lacking. So many valuable areas of research could have easily been added to this study which would have provided information that we have yet to study much. Lastly, the manner in which the researchers presented the information is so elementary compared to other peer-reviewed articles. This may be due to a language barrier and the mode by which it may have been translated into English. Nevertheless, these weaknesses are evident and hindering.
This study uses a common dairy probiotic, curd as its medium of transportation. It claims to be the first study of which this type of probiotic host has been used. Although this may be true, for the most part this study is comparable to most of the research done in this field. In fact merely confirms the research that probiotics may decrease plaque formation and have anti-inflammatory responses in the periodontal tissues (2,3,4). However, considering the use of children and a “dietary” method of probiotic delivery, this study does suggest how a normal child’s oral health may react to the introduction of a normal dietary food containing probiotics.
In summary, the study design was simple and effective. They succeeded in making a complicated subject seem uncomplicated. Their results are easy to understand and reflect results as found in similar studies. However, they had opportunities to give more to this specific field of interest. Simple points such as probiotic dosage, different time intervals, or long-term benefits were left out. But, overall we are left with something. Although not stated explicity, I believe the researchers sought to demonstrate the future of dietary probiotics in oral health in community or public programs. Truly, school children are the area of emphasis in health and nutrition. Therefore, this study is pointed in the right direction with very important future health and nutrition implications.
(1) Karuppaiah RM, Shankar S, Raj Sk, et al. Evaluation of the efficacy of probiotics in plaque reduction and gingival health maintenance among school children – A Randomized Control Trial. J Int Oral Health. 2013; 5(5):33-7.
(2) Slawik S, Staufenbiel I, Eberhard J, et al. Probiotics affect the clinical inflammatory paramers of experimental gingivitis in humans. European Journal of Clinical Nutrition.July 2011;65(7):857-863.
(3) Iniesta M, Herrera D, Montero E, et al. Probiotic effects of orally administered Lactobacillus reuteri-containing tablets on the subgingival and salivary microbiota in patients with gingivitis. A randomized clinical trial. J Clin Periodontol. 2012; 39: 736-744.
(4) Hellgren K. Assessment of Krillase chewing gum for the reduction of gingivitis and dental plaque. The Journal of Clinical Dentistry. 2009; 20(3):99-102.
Reviewed by Viktoriya Wolff