Hi Dear,
Welcome to Health Care Magic Team.
Understanding your concern about your health.
Hard swelling between your teeth and jaw line is probably due to
tooth infection in molar tooth i. e back tooth region.
You probably have large carious lesion in posterior tooth region. Bacteria and pus have been accumulating in that area which caused swelling.
As you have not visited any
dentist you are not aware of root cause. It could be an
abscess, cyst, tumor which is involving your jaw line and damaging bone over there.
You should go to your dentist immediately and get oral X-rays done.
Antibiotics first line of treatment to subside infection then if it is possible to save tooth then go for RCT(
Root canal treatment).
Otherwise extraction is the treatment for this.
Viral infection of
salivary gland, sialadentitis means inflammation of salivary glands could be a cause to this.
I would suggest you to visit dentist as soon as possible.
Hope your concern has been resolved.
Best Wishes,
Dr. Harry Maheshwari