I would definitely check into the glucose levels for possible diabetes as suggested before. Also, hormonal changes can cause many change in your oral health. Anything from electrolyte imbalances to a lack of digestive enzymes causing an overload of bacteria and yeast can also do this. This is very common for mouth breathers and accompanied by extremely bad breath. Try a few tablespoons of chlorophyll throughout the day to help with that if that is a slight issue. And you can try a daily probiotic to help with balancing any flora activity.