Whereas dental care between brushing has traditionally revolved around mouthwashes that aim to kill all bacteria, good and bad, oral probiotics attempt instead to favorably alter the balance of microflora in the mouth, said Oragenics vice president, product development Dr Bob Zahradnik.
“We're trying to use the narrow range of a rifle to tackle the problem instead of a shotgun. Antibacterial mouthwashes just indiscriminately kill everything. In conventional oral care, the only good bacteria is dead bacteria, so it’s a completely different approach.”
However, if consumers could grasp the concept of good and bad bacteria in the gut, they could apply the same reasoning to the mouth, he said. “The digestive tract starts with the lips.”
How it works
Oragenics’ ProBiora3 ingredient contains a proprietary blend of three bacterial strains that compete with harmful bacteria in the mouth.
It is based on research by chief scientific officer Dr Jeffrey Hillman, who discovered a strain of Streptococcus mutans called Streptococcus rattus (S. rattus JH145), that does not produce damaging lactic acid and competes with native caries-causing S. mutans for nutrients and space.
ProBiora3 also contains the naturally-occurring oral bacteria Streptococcus oralis (S. oralis KJ3) and Streptococcus uberis (S. uberis KJ2), which produce a continuous low dose of hydrogen peroxide, which gradually whitens teeth.
By binding to the teeth and deep beneath the gum line, they also leave little room or nutrients for bad-breath causing bacteria to flourish, helping to freshen breath, said Zahradnik.
Health claims
Oragenics is currently making cosmetic (teeth whitening) and structure/function claims (helps maintain tooth and gum health) about ProBiora3, said Zahradnik.
But bosses were confident it would be able to support far stronger health claims in future as more clinical trials were completed, he added.
“We are aiming for something like: ‘ProBiora3 can lower levels of Streptococcus mutans in the mouth. Streptococcus mutans is a known risk factor for dental decay’.”
A feasibility study published in the Journal of Applied Microbiology in 2009 had shown that ProBiora3 was safe and could substantially decrease levels of known harmful bacteria in the mouth, he said.
“We’ve taken the learnings from this to help get the right protocols in our next set of clinical trials.”
He added: “The good thing about oral probiotics is that you can access the area you are trying to impact much more easily to take samples and observe changes than you can with digestive health products, which means it is much easier to prove your products work.”
Delivery vehicles
While Oragenics had launched its own consumer products (EvoraKids chews, EvoraPlus mints and EvoraPro mints) containing ProBiora3 to raise awareness and provide a proof of concept, its focus was on supplying it as an ingredient to supplement manufacturers or food companies keen to incorporate it into their products, he said.
“ProBiora is now in products in 20 countries, and we are in advanced talks with companies looking at a range of applications from gums and mints to dairy products. The key is that the delivery vehicle must have low water activity, and a pH range of 3.5 to 8.5. We’re very confident that we can assign an 18-month shelf life to products stored correctly at room temperature.
“The probiotics are freeze dried, tasteless and odorless and only need 10 seconds or so to activate in your saliva and attach to sites in the mouth. They are natural colonizers of the mouth.”
Dissolvable strips were a particularly good delivery vehicle, he said.
“The challenge has been that the way these are usually made is that you have a polymer, you add the active and then add a solvent. But that’s not compatible with probiotics, so we’re working with a partner to produce them using a different, patented technology.”
S. mutans binds to teeth via aggregation, forming dental plaque. The bacteria then convert sugar to acid, which attacks the enamel of the teeth.