Arginine is already in saliva. Some beneficial oral bacteria can change arginine into compounds that counteract the tooth enamel-damaging acids that sugar converts to. Arginine can also change the makeup of dental biofilms to make them less harmful.
The small study used 12 people with cavities. They were fitted with special dentures that allowed biofilms to grow on both sides of the jaw so researchers could compare treatments in the same mouth. Three times a day, the dentures were soaked in a sugar mixture for five minutes. Then, for 30 minutes, one side would get soaked with distilled water and the other with arginine.
“The aim was to investigate the impact of arginine treatment on the acidity, type of bacteria, and the carbohydrate matrix of biofilms from patients with active [cavities],” said Sebastian Schlafer, professor of Dentistry and Oral Health at Aarhus Univ.
The researchers saw that the biofilm that formed on the arginine side of the dentures protected against acids from sugar. Even 35 minutes after being exposed to sugar, the biofilm still maintained its integrity against the acid. The biofilm also contained fewer fucose-based carbohydrates. That may be why they appeared to be less harmful. And the bacteria present in the arginine biofilm were ones that improved the pH and made them less harmful for teeth.
“Our results revealed differences in acidity of the biofilms, with the ones treated with arginine being significantly more protected against acidification caused by sugar metabolism,” said Yumi Del Rey, microbiologist at Aarhus Univ.
Older research had suggested arginine plays a role in preventing tooth decay. But the studies were lab experiments that weren’t conducted with human mouths. As this study used actual people, its results are more telling.
However, while it was well controlled, it’s essential to note how small the test group was. The results varied between participants, with some people not responding to the treatment, and the researchers weren’t able to link the lack of an outcome to any clear variable. More, larger studies are needed to learn if this is something that could have practical applications. Arginine is in the body and already used to treat blood pressure concerns. So, as studies already show it’s safe, if other studies confirm its oral benefits, this could be massively beneficial.
