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Effect of Probiotic Yogurt on Salivary Bacterial Count and pH when Used as a Mouth Rinse - An In vivo Pilot Study
Sreelakshmi Rajendran1, Rena Ephraim1, Selvakumar Chinnasamy2
1Department of Paediatric and Preventive Dentistry, Mahe Institute of Dental Sciences and Hospital, Puducherry, India.
Introduction:
Probiotics, especially probiotic yogurt, are the most herbal manner to alter the bacterial flora in the gut. It has been found to make the oral and gut environment favourable for those bacteria that can reduce the acidity and promote health and increase immunity of an individual.
Aim:
To assess the effect of probiotic yogurt on the bacterial count and the pH of saliva when used as a mouth rinse.
Materials And Methods:
The study was conducted after clearance from the Institutional Ethics Committee. After getting parental consent, 20 children aged between 5 and 8 years with decayed, missing, filled scores above five were selected for the study. Two ml of unstimulated saliva was collected and its pH was assessed. The saliva was inoculated into brain heart infusion agar and incubated for 24 h. The baseline bacterial colony count was conducted. The participants were asked to rinse with probiotic yogurt once after a main meal every day for 7 days. On the 8 th day, 2 ml of unstimulated saliva was collected again to assess the post-operative values. The pH of the sample, the bacterial colony count, and the predominant species of microorganisms were analysed and compared.
Results:
After 7 days of rinsing with probiotic yogurt, the salivary pH significantly increased, indicating reduced acidity. The bacterial count showed a decrease in the count. The bacteria that were found after post-operative analysis were the presence of less pathogenic bacteria present in the oral cavity.
Conclusion:
Probiotic yogurt can be used as a mouth rinse for effectively changing the bacterial flora by reducing pH and bacterial colony count, which can help reduce the susceptibility of the individual to caries attack.
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