There's a white substance on both inner cheeks, right behind the bottom row of teeth. I did a swab and it came back clean. I showed the dentist and she said it's
Chronic cheek biting | Chronic cheek bites
7 Reasons The Skin Inside Your Mouth Is Peeling Off
Oral mucosal peeling | British Dental Journal
Some odd flap of skin inside of a mouth with white dot. : r/Dentists