You can try cleaning your teeth and gums by brushing with hydrogen peroxide a few times a day. It foams a LOT, so you will have to keep spitting the foam out, but brush good with a soft or medium toothbrush. Get a new toothbrush often...they are full of bacteria.
Seeing a dentist is not the only way, but you will have to work on those gums and keep the teeth clean.
You may need antibiotics from the doctor as well.
(Whenever I see a dentist for cleaning they are astounded how clean they are and they virtually do nothing to them. Dentists aren't the only solution.
I always use mothwash to brush, and never use toothpaste.I clean my own teeth of tartar and such, with a pick.)