Brief Answer:
most likely due to sharpening of teeth or faulty upper and lower jaws appos

Detailed Answer:
Hi XXXX,
Thanks for posting query.
Read your query and saw the picture of oral cavity you sent.
It seems that as white straight line seen are situated in inner cheek are exactly in line where your line of your upper and lower teeth meet.
This indicates that there might be having sharpening of outer margin of your teeth leading to constant minor trauma to your oral mucosa resulting fibrosis in that line.
As you get bites un-intetionally bite in inner cheeks also shows that outer margin of your teeth is sharp.
There is also a possibility of having some anatomically problem of apposition of upper and lower jaws leading to un-equal pressure exerting while chewing.
This can be due to some problem with your TM joint as well.
This type of white opacity can occur having sub-mucous fibrosis as well.
I advice to consult dental surgeon and if require oral surgeon to know exact nature of your this lesion.
If there are sharpening of outer margin, with treatment this can be treated with removing sharpening of teeth.
Seeing picture it seems that there is nothing dangerous like pre-cancerous lesion.
Leave habit of having tobacco chewing or Gutkha if you are having.
Meanwhile do Feel fresh or Listerine gargles.
Take care while chewing food or making any haste while taking food.
I hope I answered your query.
If you have further query or any clarification, please write me back.
Wish you speedy recovery.

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Brief Answer:
Apply glycerine gel or Chlorhexidine cream

Detailed Answer:
Hi XXXX,
Thanks for posting query again.
You can apply Glycerine gel for smoothing and Chlorhexidine cream over white line for having any mild infection.
Seeing the nature of linear lesion there is nothing to worry about serious disease.
Do gargling with Feel fresh or Listerine gargles.
Ok and take care.
Dr. Ramesh Vachharajani, XXXXXXX XXXXXXX XXXXXXX

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