White patches on oral mucosa (Leukoplakia) is a common finding that can be caused by so many different things. Some are not worrisome and easily treatable such as fungal infections, while others are more serious and warrant more attention. The fact that yours are easily detachable is reassuring, especially if they don't bleed while sloughing off. The associated dryness you are complaining of can be a cause of that by itself. However, you should test your blood sugar level, as Diabetes can cause both dryness and white oral detachable patches at the same time. If it persists, have it looked at by a professional. Hope this helps.
I would recommend:
- don't eat and sleep
- never sleep without brushing and mouth washing
- do a complete mouth and teeth check up to remove all possible relation with the teeth
- do not use mouthwash with Alcohol
- if you smoke, I think this is simply the cause