What are probiotics?

Probiotics are living microorganisms, particularly lactic acid bacteria (Lactobacilli), which when ingested in sufficient quantities have beneficial effects on human health. Probiotics work by successfully competing with pathogenic microorganisms for living space, by secreting various antimicrobial substances (e.g. hydrogen peroxyde) and thus directly suppressing pathogens, by changing the pH of the environment making it unhospitable for the pathogens, or by beneficially modulating the immune response of the host.

Bacteria from yoghurt and other cultured dairy products are the most important source of probiotics in our diet. Most probiotic bacteria belong to the Lactobacillus, Bifidobacterium, Propionibacterium and Streptococcus strains*.

The oral flora

In a state of health, our mouth flora consists of about 10 billion beneficial bacteria which are helping to keep our teeth, gums and mucosa healthy by suppressing pathogens (like cavity and gum disease causing bacteria, viruses and fungi) which live on and unless checked, eventually destroy our tooth and gum tissues.

Cavities, gingivitis and mouth sores are all due to a similar problem: noxious pathogens have multiplied and dig into your teeth and gums or attack your oral mucosa.

In other words, your mouth flora has been overwhelmed by harmful microorganisms and is no longer able to keep the pathogens in check.

Bad breath of course unless due to foods like garlic or systemic causes such as SIBO (small intestinal bacterial overgrowth) is also caused by bad bacteria, in this case anaerobic bacteria hiding between your teeth and living on your tongue which as they multiply produce VSCs (volatile sulfuric compounds) which do not smell good.

Beneficial probiotic bacteria prevent and treat oral infections, including cavities, gum disease and bad breath

In 2009, Japanese scientists studied the bacterial composition of the oral flora of 66 individuals[1]. They found that the higher the percentage of Lactobacilli in their oral flora, the better they were able to fight off the attacks of pathogenic bacteria. Other studies showed that Lactobacilli were working to fight against cavities[2], dental plaque and gingivitis[3] and help against periodontitis[4].

There are probiotic strains which are particularly effective in suppressing cavity-causing and gum-destroying bacteria. There are products formulated to this effect which flood the mouth with beneficial bacteria. They are best taken after meals and need to be taken continuously since your oral flora is constantly changing depending particularly on your diet and stress level.

You can also ferment your own yoghurt using beneficial strains as a starter culture and regularly conclude your meals with it.

Chemical mouthwashes and your oral flora

Chemical compounds do kill the bad bacteria, but also the good ones (examples are chlorhexidine, alcohol and fluoride) so should only be used when there is a clear preponderance of bad bacteria (rampant tooth decay, toothache, gum disease, bad breath) in your mouth.

Otherwise it is better to implant and strengthen the beneficial bacteria which when they have the upper hand, will crowd out the bad ones (a similar process as what happens in the gut when ingesting large amounts of probiotics).

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1 Probiotic effects of orally administered Lactobacillus salivarius WB21-containing tablets on periodontopathic bacteria: a double-blinded, placebo-controlled, randomized clinical trial, Journal of clinical periodontology 36, no 6 (2009): 506–513.

2 Reversal of primary root caries lesions after daily intake of milk supplemented with fluoride and probiotic lactobacilli in older adults, Acta Odontologica Scandinavica 69, no 6 (2011): 321–327.

3 Effect of Probiotic Mouth Rinse on Plaque and Gingivitis

4 Clinical and microbiological effects of Lactobacillus reuteri probiotics in the treatment of chronic periodontitis: a randomized placebo-controlled study », Journal of clinical periodontology 40, no 11 (2013): 1025–1035.

Dental self-healing