Periodontitis, also called gum disease, is a serious gum infection that damages the soft tissue and, without treatment, can destroy the bone that supports your teeth. Periodontitis can cause teeth to loosen or lead to tooth loss. Periodontitis is common but largely preventable. It’s usually the result of poor oral hygiene. Brushing at least twice a day, flossing daily and getting regular dental checkups can greatly improve your chances of successful treatment for periodontitis and can also reduce your chance of developing it.