What are Probiotics K-12 & M-18?

Probiotics S. salivarius K12 and S. salivarius M18 Strengthen Oral Health

Numerous studies have shown that the use of the oral probiotics S. salivarius K12 and M18 may improve oral health through the reduction of cariogenic and periodontal pathogens levels in addition to other major health benefits. Probiotics regulate cytokine concentrations, which is the inflammation associated with red puffy gums. These strains also lower the crevicular fluid volume or the fluid that surround the inflammation.  

Two types of S. salivarius bacteria found in the mouth may have benefits in the dentistry and oral care arenas — S. salivarius K12 and S. salivarius M18. S. salivarius produces three types of antimicrobial agents: Salivaricin A, Salivaricin B and Salivaricin 9 (1, 2, 3 and 4).

Commercially available BLIS K12 and M18 products contain antibacterial molecules that may offer preventative and remedial solutions to patients to attack the root of  gingivitis and periodontal disease.

S. salivarius K12

S. salivarius K12 is a probiotic that has the ability to fight infections. It produces two significantly powerful proteins: the bacteriostatic peptide Salivaricin A and bactericidal peptide Salivaricin B. Both are referred to as “bacteriocin-like inhibitory substances” or BLIS. Studies show Salivaricin A and Salivaricin B attack invasive bacteria by colonizing in the oral cavity.

The colonization process prevents pathogenic bacteria from sticking to the host. The build of up pathogens create an imbalance in the flora environment and contribute to dental cavities, halitosis, sore throats and ear infections. The BLIS molecules Salivaricin A and Salivaricin B target and attack these pathogens. K12 communicates with specific cells in the mouth to excite them and increase the body's immune system. K12 also protects the ears, nose, mouth and throat against infection.

Streptococcus pyogenes cause a variety of health issues including strep throat (3, 4, 5). Research shows children with S. salivarius K12 have a 50 percent less chance of the strep throat bacteria and may experience fewer ear infections. Often, mouthwashes mask symptoms of a problem and kill both good and bad bacteria. However, BLIS-K12 equalizes the flora in the oral cavity and allows room for the good bacteria to thrive.

In July 2008, Infection and Immunity published a study which revealed BLIS K12 not only altered the responses of the body’s immune and natural defense systems, but upon further investigation, researchers determined that S. salivarius K12 also transformed genes “associated with other bodily functions, including transcription and translation, protein trafficking and exocytosis, and nucleoside and phosphate metabolism(6).”  S. salivarius K12 also demonstrated a substantial effect on the adhesion and structural qualities of the bronchial epithelial cells. The researchers surmise these attributes made the association between S. salivarius K12 and the host stronger and help “maintain the tight junctions of cells on epithelial surfaces (13).”

The ability of S. salivarius K12 to affect physiological response and natural defenses provides assurances that the host accepts the modulations and fosters an environment for cellular and overall health. Furthermore, it protects tissue against damage from other immunostimulatory cells and products.

Where to find K12?

TheraBreath Probiotics contain over 1 billion cultures of K12 probiotics bacteria, which attack bad bacteria present in the mouth. Within 7 days, the gum's Aktiv-K12 bacteria take root and defend the oral cavity from bacterial damage. One treatment per month helps the patient maintain a healthy flora balance in the oral cavity.

What is S. salivarius M18?

S. salivarius M18 produces bacteria that prevent cavities and breaks-up dental plaque in the oral cavity.  The BLIS M 18 bacteria derive from a specific S. Salivarius strain — Streptococcus salivarius. About two percent of the global populace (people who rarely experience plaque or tooth decay) has the Streptococcus salivarius necessary to make the M18 peptides.

The agent Salivaricin 9 destroys the primary generator of lactic acid called Streptococcus mutans or S. mutans. Lactic acid leads to cavities by attacking and eating away at tooth enamel. The acid also damages the cementum, which is the natural layer of calcified substance that covers the root of a tooth. Loss of cementum heightens tooth sensitivity to the touch, as well as hot and cold temperatures (4, 5, and 6).

Researchers discovered the BLIS M 18 microbial’s proven attributes and natural ability to prevent Streptococcus mutans or S. mutans — a leading contributor to cavities and tooth decay. They also discovered M18 converted urea, a natural enzyme found in saliva, into ammonia.  Ammonia plays a significant role in neutralizing the lactic acid from dietary carbohydrates, which creates cavities and damages the tooth structure.

M18 also produces the natural enzyme called Dextranse.  Dextranse inhibits the development of dextrans or extracellular polysaccharides. Eliminating these polysaccharides leads to the prevention of oral health challenges such as plaque, biofilm, tongue coating, staining, cavities and periodontal disease. Patients also experience an improvement in overall health.

M18 is effective in preventing acid erosion caused by foods with high acidity that would otherwise eat away the tooth enamel (5, 7 and 8).

Wescombe and others discuss the role of lantibiotics in maintaining a “microbiota of oral mucosal surfaces” such as Salivaricin 9 (Sa19).  They discuss “the availability of technology for transfer of S. salivarius mega plasmids to plasmid-free S. salivarius now facilitates the tailor-making of designer probiotic strains containing desirable combinations of BLIS armoury, colonization efficiency and immune stimulatory capability. The probiotic potential of S. salivarius should continue to maintain research interest in the further characterization of novel inhibitors produced by this species.”  The point is that probiotic based products can be developed using advanced technology to help improve oral health. 


Establishing good oral health is key to patients maintaining their overall health. Oral care probiotics that contain S. salivarius K12 and M18 have been proven safe, natural and free of side effects. These characteristics present attractive options for periodontal applications. Studies show gum and rinses which contain probiotics prevent volatile sulfur compounds (VSCs) attributed to bad breath halitosis. In addition, patients with periodontal disease can also realize health benefits from probiotics.

TheraBreath has Oral Care Probiotics that provide patients protection from “bad bacteria” on all fronts including cavities, halitosis, plaque, acid erosion, unsightly gums and other oral care challenges. We suggest that dental professionals recommend to their patients a treatment protocol that includes the TheraBreath toothpaste, oral rinse and the multi-symptom probiotics blend for a comprehensive oral health preventative program.

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.



Iva Stamatova, MD and Jukka H. Merurman, MD, PHD, “Probiotics: Health benefits in the mouth.”

http://www.amjdent.com/Archive/2009/Stamatova%20-%20December%202009.pdfAmerican Journal of Dentistry, Vol. 22, No. 6, December 2009


Paul E. Kolenbrander, et al. 2010. “Oral multispecies biofilm development and the key role of cell–cell distance.”

http://www.endoexperience.com/documents/Oralmultispeciesbiofilm.pdf.  Natures Reviews, July 2010.


C. E. Kazor, et al. 2003. “Diversity of Bacterial Populations on the Tongue Dorsa of Patients with Halitosis and Healthy Patients.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC149706/?tool=pubmed. Clin Microbiol. February 2003.


Jeremy P. Burton, et al. 2006. “Safety Assessment of the Oral Cavity Probiotic Streptococcus salivarius K12.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449041/?tool=pmcentrez.  Appl Environ Microbiol,  April 2006.


Celine Cosseau, et al. 2008. “The Commensal Streptococcus salivarius K12 Downregulates the Innate Immune Responses of Human Epithelial Cells and Promotes Host-Microbe Homeostasis.”

Infection and Immunity, Sept. 2008.


Gardy, Chikatamarla, Gellatly, Cosseau,  Devine, Dullaghan ,Hancock,  Yu,  Pistolic, Falsafi and  Tagg “Responses of Human Epithelial Cells and K12 Downregulates the Innate Immune

The Commensal Streptococcus salivariusPromotes Host-Microbe Homeostasis.”

http://iai.asm.org/content/76/9/4163.full.pdf  Infection and Immunity July 2008.


Tony Walls, Power and Tagg,Bacteriocin-like inhibitory substance (BLIS) production by the normal flora of the nasopharynx:potential to protect against otitis media?”

http://www.bio-genesis.com/productpages/pro-flora-oral-health/Pro%20Flora%20Research%20Pack.pdf. Journal of Medical Microbiology (2003)


Professor Lawrence J. Walsh,“On the nose - new diagnostic and

treatment approaches for oral malodour.”

http://espace.library.uq.edu.au/eserv/UQ:78943/Halitosis.pdf. Dental Practice, July/August 2066


Laetitia Bonifait, DEA; Fatiha Chandad, PhD; Daniel GrenierPhD, “Probiotics for Oral Health: Myth or Reality?”

http://www.cda-adc.ca/jcda/vol-75/issue-8/585.pdf. JCDA,October 2009, Vol. 75, No. 8


Burton JP, Chilcott, Moore, Speiser and Tagg. “A preliminary study of the effect of probiotic Streptococcus salivarius K12 on oral malodour parameters.”

http://www.ncbi.nlm.nih.gov/pubmed/16553730. J Appl Microbiol April 2006


Nicholas C. K.,   et al. “Genome Sequence of the Bacteriocin-Producing Oral Probiotic Streptococcus salivarius Strain M18.”



Antonio-Juan Flichy-Fernández. 2010 “Probiotic treatment in the oral cavity: An update.”

http://www.medicinaoral.com/pubmed/medoralv15_i5_p677.pdf . Med Oral Patol Oral Cir Bucal. September 2010.


P.A. Wescombe, et al. 2011. “Salivaricin 9, a new lantibiotic produced by Streptococcus salivarius.”

http://mic.sgmjournals.org/content/157/5/1290.full.pdf. Microbiology 2011.


Davidson College Biology Department. “Epithelial Cells.”


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