Ideally, teeth need to be in firm contact with the teeth in front and behind them.
This prevents food from packing between the teeth when chewing takes place.
When this normal pattern is broken, small spaces can open between the teeth.
Food will then be forced into these spaces between the teeth, and into the gum.
This sets up an irritation, and the gum becomes inflamed, swollen, red and painful.
This inflammation can also spread to other areas around the tooth, and can cause the tooth to become tender on chewing.
Toothbrushing and the use of dental floss, interdental sticks or interdental brushes will help to control the problem. It should be corrected by a dentist.