Probiotic-based therapeutic approaches are relatively new to the field of clinical dentistry. According to a recent review published in Frontiers in Dental Medicine, probiotic-based therapy in conjunction with established treatment regimens can effectively combat gingivitis and periodontitis.

Oral microbiome 

The human microbiome consists of millions of microorganisms that inhabit various body parts, including the gut, oral cavity, skin, and mucosa. The oral microbiome is the second largest microbial community in humans after the gut microbiome. The oral epithelia are infested with many bacteria, forming the bacterial biofilm.

Probiotics: Mechanism, safety, and commercial aspect 

Probiotics are beneficial microbes that modulate the immune response, provide a source of essential nutrients, and inhibit the proliferation and virulence of infectious agents. Probiotics interfere with the growth and metabolism of competing microorganisms via two mechanisms. The first method involves specific interference, in which bacteriocins (peptides) eradicate competing bacteria or alter their metabolism, thus impeding biofilm formation. A second mechanism is an indirect interference, in which microbial competitors are destroyed by inducing nitrosative, oxidative, or acidic stress. 

Probiotics in the management of chronic gingivitis and periodontitis

Several studies delineated that probiotics dramatically reduced gingival inflammation as an adjuvant to effective mechanical plaque management; however, only moderate effects were reported in others. In study cohorts with insufficient mechanical plaque control or experimental gingivitis trials, the outcomes remained equivocal. On the other hand, in RCTs with the same L. reuteri probiotic use, subjects with poor dental hygiene with clinical symptoms of chronic gingivitis were investigated. The probiotic use led to significant reductions in gingival inflammation despite little or no improvements in oral hygiene measures.

Conclusion

Certain questions regarding the use of probiotics in the treatment of gingivitis and periodontitis remain unanswered. Meanwhile, guidelines based on broad consensus specifying the selection of the appropriate probiotic, dosage, and duration of administration are lacking. RCTs investigating the benefits of probiotic use in clinical dentistry can add a valuable element to the available therapeutic options.