According to MedlinePlus, loose teeth in adults are primarily related to periodontitis, or an infection or inflammation of the gums, that is left untreated. The inflammation then spreads to the ligaments and bones that hold teeth in place, causing them to become loose and fall out eventually. Because bacteria is present in plaque, infection commonly occurs concurrently and develops into a tooth abscess, which hastens the rate of bone destruction.
When a loose tooth occurs, a dentist is able to support it in the early stages, Medline explains, but in advanced cases the tooth must be removed to prevent the spread of inflammation to neighboring teeth. Early symptoms of periodontitis greatly resemble gingivitis and include bad breath and swollen gums. Gums are tender to the touch, bleed easily and have a shiny appearance.
According to MedlinePlus, an examination by a dentist typically reveals soft, red-purple gums with deposits of calculus and plaque at the surface of the teeth as well as enlarged pockets in the gums. Dental X-rays verify periodontitis by showing the loss of supporting bone and presence of plaque under the gums. Regular cleanings by a dentist and regular brushing and flossing of the teeth help to prevent the loss of teeth and gum disease.