Thanks for asking the query,
Due to trauma from broken tooth you have developed an ulceration on the on the cheek mucosa.
I would suggest you to visit the Dentist
and you can get the sharp bordres of the wisdom tooth removed by selective grinding,or else take an x-ray of the tooth and you can go for extraction of the tooth.
Wisdom tooth does not have nay significant role in mastication and occlussion so its better to get it extracted if causing trouble.
Apply Dologel oral ointment topically over the affected area.
Maintain a good oral hygiene
use antiseptic mouthwash gargles twice daily.
Hope this helps out.