Your symptoms suggest a condition called Oral Submucous Fibrosis (OSMF). This condition arises due to gutkha and supari usage and is considered a precancerous condition, that is, it can progress to oral cancer
if allowed to progress. Thus, the first necessary component of treatment has to be a complete
cessation of the habit. You need to consult with a dentist
or an oral surgeon for assessment and necessary treatment. Treatment would usually be symptomatic in nature, aimed at improving comfort and mouth opening, and involve lifelong physiotherapy
. You need to understand that the cellular changes causing the symptoms are permanent and can progress further if the gutkha habits are resumed at any time in the future.