OSMF is curable. Depending upon severity of OSMF (HOW MUCH MOUTH OPENING IS PRESENT) treatments varies. Since you have already quit the habit, whatever treatment is required in your case will be very very effective. The most basic treatment is to take antioxidants like lycopene
, jaw exercises like keeping wooden spoon bundle in mouth at maximum jaw opening for two times daily for 10 to 15 minutes, increasing one spoon daily until required jaw opening achieved.
The most advanced treatment is undergoing LASER
surgery for cheek fibers which has excellent outcome in ultra short duration compared to conservative approach. For more details you can personally contact me.