Cuts on the tongue and mouth imply the possibility of different causes such as minor injuries and viral, fungal or bacterial infections, explains Healthline. A weakened immune system due to sickness, bleeding disorders or a reaction to some over-the-counter prescriptions could be other possible reasons.
Minor causes such as tongue bite, burning the mouth, irritation from sharp objects such as dentures or braces, using a firm toothbrush or brushing teeth too hard contribute to most cuts on tongue and gums, notes Healthline. The herpes simplex virus also leads to sores on gums and tongue. Hormone changes, vitamin deficiencies, especially B-12, and intestinal issues such as irritable bowel syndrome also cause canker sores in the mouth that affect gums and mouth, as reported by the New York Times.