The antibacterial effect of Magnolia mouthwash on the levels of salivary Streptococcus mutans in dental plaque: a randomized, single-blind, placebo-controlled trial

Dental caries is one of the most common chronic diseases around the world. Inhibitory effects of Magnolia Grandiflora bark extract has been proved on tooth decay both in vitro and by using free sugar chewing gum. This research aimed to examine the effect of Magnolia Grandiflora bark mouth-wash on the prevalence of Streptococcus mutans in dental plaque.

This crossover, placebo-controlled, clinical trial study, was performed on a total of twenty participants (aged 18 to 35 years) in both control and intervention groups and four phases. The prevalence of S. mutans was measured in a certain volume of volunteer’s dental plaque at the beginning of the project (phase 1), after the first prescription (phase 2), following the washout period (phase 3) and finally after the second prescription (phase 4) by culture on bacteriology medium. Plaque index and saliva sampling were carried out in follow-up visits by a dentist. The data were analyzed using T-Test (paired and independent) quantitatively.

There was a significant difference in S. mutans frequency in dental plaque between when the participants used Magnolia mouthwash and when they washed out or used a placebo (p<0.005). Results also showed a significant difference between Magnolia and Placebo groups in the mean count of saliva bacterial colony counts after oral administration in the first and second time (P<0.001 and P<0.004, respectively).

The current trial showed that Magnolia Grandiflora %0.3 mouthwash tends to decrease the number of S. mutans in dental plaque significantly. Therefore, its mass production and release to the oral health community are suggested. However, further studies with larger sample sizes and varying treatment are required to substantiate the findings of this study.