Research indicates that functional similarities exist between gastrointestinal and oral microbiota. Certain probiotics have been shown in research to promote healthy oral microbial balance. Studies have also pointed to the potential ability of probiotics to reduce the bacterial load of certain pathogens and possibly prevent bacterial growth and biofilm formation in the oral cavity. Improvements in certain clinical markers related to periodontitis have also been observed in studies involving certain probiotics related to oral health.

A review article explored the efficacy of the oral application of probiotics on apical periodontitis (AP). This condition is characterized by pathogenic microbial invasion of dental pulp and involves an inflammatory response of periradicular tissue. It has been associated with certain systemic pathologies related to cardiovascular and metabolic health.

One animal study reported that certain strains of Lactobacillus and Bifidobacterium helped support a healthy response to inflammation in the oral cavity. They also exhibited antimicrobial activity against certain endodontic pathogens, which included Candida albicans and Enterococcus faecalis. Another animal study demonstrated attenuation of periapical bone loss in the presence of oral probiotic supplementation.

In clinical studies, the application of Lactobacillus paracasei (L. paracasei) was shown to significantly reduce gingival inflammation. Applications of L. paracasei have also been shown to have activity supporting dental structural health.

A randomized, placebo-controlled clinical trial assessed the efficacy of milk powder with L. paracasei on the population of certain pathogenic bacteria, including Streptococcus mutans (S. mutans). There were 40 children as participants of this 6-month long study. In the probiotic treatment arm, populations of total Streptococci and S. mutans were significantly lower and salivary immunoglobulin A (IgA) was higher as compared to the placebo group.

Probiotics may also support the body’s ability to maintain bone health. An animal study indicated that supplementation with probiotics influenced bone metabolism. This is believed to be due to their ability to support the body’s natural response to inflammation and their likely role in the signaling of certain molecules related to osteoclastogenesis, such as RANK ligand and osteoprotegerin. 

A comparison study was conducted with PerioBiotic™ probiotic toothpaste containing L. paracasei. Study subjects brushed twice daily for 2 weeks. PerioBiotic™ was shown to significantly decrease populations of S. mutans as compared with other toothpaste options available on the market. The efficacy of PerioBiotic™ was also assessed in a pilot study. PerioBiotic™ was shown to reduce the S. mutans load for up to 90 minutes after brushing.

Lactobacillus paracasei is a probiotic that has been shown in research to help support oral microbial balance. Similar to the role of probiotics in the gastrointestinal tract, beneficial flora of the mouth may help maintain dental and oral health.* Lactobacillus spp. can be found in sauerkraut, kefir, grass-fed yogurt, tempeh, and other naturally fermented foods. 

By Colleen Ambrose, ND, MAT