Arginine supplementation can safely prevent dental caries, even in children

A new study has discovered that arginine can change plaque formation, thereby protecting against dental caries. This amino acid is also naturally present in saliva and can safely be used, even for children’s products.

Researchers from Aarhus University, Denmark, suggest that their finding offers potential for arginine supplementation in dental care products for effectively preventing tooth decay.

The team collected dental biofilms, or plaque, which are caused by bacterial fermentation of dietary sugars that leads to tooth decay. 

The study in the International Journal of Oral Science included 12 participants with caries using specialized dentures. These were used to test arginine’s effects alongside a placebo.

Neutralizing acidity

The researchers explain that some beneficial bacteria have an arginine deiminase system that enables arginine to break down into an alkali that neutralizes acids. So increasing arginine helps the beneficial bacteria grow while preventing the growth of acid-producing bacteria.

Arginine can reduce plaque acidity and shift oral biofilms toward a less decay-promoting state.In the study, researchers prepared specialized dentures that collected intact biofilms from both sides of the jaw. Participants then dipped the dentures in a sugar solution for five minutes on each side, followed by distilled water (placebo) or arginine for 30 minutes on each side.

They repeated this process three times a day, and on the fourth day, when the biofilm was developed, the dentures underwent analysis.

“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 caries,” explains Sebastian Schlafer, professor at the Department of Dentistry and Oral Health.

The authors say their study is the first to analyze the effects of arginine on biofilm composition, carbohydrate matrix architecture, and microscale pH of biofilms from caries.

Biofilms under the lens

In the trial, a pH-sensitive dye (C-SNARF-4) was used to analyze the acidity of the biofilms in different locations. 

The researchers found that biofilms treated with arginine have significantly high pH, meaning lower acidity, 10 and 35 minutes after the sugar dip.

“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,” says the first author, Yumi C. Del Rey.

Arginine treatment reduced the amount of fucose-based carbohydrates, suggesting the biofilms were less harmful. Carbohydrate components, fucose and galactose, made up a large portion of biofilm. The researchers posit that they may contribute to creating “acidic pockets” inside them.

Another change involved galactose-containing carbohydrates, which decreased at the bottom and increased at the top.

Bacterial changes

Researchers also used 16S rRNA gene sequencing to identify the bacteria present in the biofilm. 

Streptococcus and Veillonella species dominated the arginine- and placebo-treated biofilms. Although arginine reduced the mitis/oralis group of streptococci that produce acid.

Arginine ultimately reduced the acidity and changed the carbohydrate structure and microbiomes within them.

In other oral health updates, research found that people with type 2 diabetes have higher tooth decay than others because sugars move from blood to saliva, causing oral microbiome dysbiosis.

Additionally, people practicing a diet “close to the Mediterranean diet” have a higher chance of better gum health, with potentially lower gum disease and inflammation, according to another study.