What causes your gums to turn white?

Needs to be seen: It's impossible to tell you what you have without actually seeing you. Three things that come to mind are lichen planus, oral candidiasis and leukoplakia. See your dentist who can tell you exactly what you have and what treatment is needed, if any.

Bacteria: You are not cleaning your gums and the bacteria has found a home. Brush in circles with a soft toothbrush. Then follow it up by using a water pik spraying the water in circles where the teeth and the gums join.