OMG dear patient,I personally always hope that people should be aware of side effects of chewing Guthka,that u must be knowing.
The condition is called as OSMF and due to stiffening of orofacial mucosa.N normally when u open ur mouth one must be able to put 4 digits of a hand at a time. But in ur case this is not so
Treatment will be long lasting
1. Quit the habit completely which is difficult if u do it suddenly so better cut down the habit slowly slowly ,u can take a help from commercial products like Nicotex/nicorette
2.Take multivitamin like tab.SM fibro 2 times a day for 3 months along with
vitamin E
3.If the symptoms aren't relieved visit ur nearest dentist so that he will inject some agents like steroid (inj.Kanacort) in those stiffened fibres to break then and make ur mouth flexible
4.Do the physiotherapy like blowing of balloons etc.
Next Steps
Life is beautiful if u quit the habits ASAP.