A team of US researchers has identified a new bacteria that may keep bad bacteria in check and can help prevent oral cavities using probiotics. According to researchers the findings could lead to the development of a supplement that patients could take orally to prevent cavities. A12 bacteria has a potent ability to battle a particularly harmful kind of streptococcal bacteria which metabolises sugar into lactic acid contributing to acidic conditions in the mouth that form cavities. The researchers found that A12 not only helps neutralise acid by metabolising arginine in the mouth it also often kills Streptococcus mutans. (Read: