Warning! Photos may be triggering and maybe even dangerous for you to view. Beware of suggestion when dealing with the problem of self-injury!
This is a photo from a site that promotes an antiseptic ointment for mouth ulcers. Although this is a photo of a canker sore, this is also often the way that an open mouth cut looks when inflamed, before it has grown a protective coating over it. Unfortunately, the protective coatings generated by the buccal mucosa rather quickly often give the self injurer brand new fodder for her intoxicating addiction, and this can lead to very unhealthful circumstances, like infections. Although the cuts do not always get inflamed like this because of body chemistry, hygiene, and other factors at the time, when the rim of the cut is inflamed like this it is very, very painful at this stage. Oral ointments that kill bacteria and help numb temporarily can often be a huge help.
Cheek Biting(Morsicatio Buccarum)
This image depicts the inside cheek of a patient who has been biting her cheek for many years.