Reaction to Certain Bacteria
Mouth ulcers caused by bacteria are redder and more painful. Streptococcus and Actinomyces are common mouth ulcers that spread by talking, coughing, and sneezing. This bacteria can easily be transferred from one person to another. Tiny respiratory droplets which contain the bacteria are transmitted through bodily functions.
Another bacteria-causing mouth ulcer is Actinomyces from a painful pus group. The collection of pus-filled pockets is called an abscess. Like mouth sores, an abscess can heal on its own. But severe abscess cases will lead to mouth ulcers or canker sores.
Aside from Streptococcus and Actinomyces, bacteria-causing mouth ulcers include syphilis or gonorrhea. These bacteria are known to spread pus-filled pockets around the soft tissues on the cheeks. It usually starts as a painless sore that grows in the mouth and cheek. However, the sore will eventually and gradually become painful as it heals on its own.
