Question: what are the main causes tooth loss?

Reference:
 Tooth abscess Periapical abscess Dental abscess Tooth infection Abscess - tooth Summary A tooth abscess is a buildup of infected material (pus) in the center of a tooth. It is an infection caused by bacteria. Causes A tooth abscess may form if there is tooth decay. It may also occur when a tooth is broken, chipped, or injured in other ways. Openings in the tooth enamel allow bacteria to infect the center of the tooth (the pulp). Infection may spread from the root of the tooth to the bones supporting the tooth. Infection results in a buildup of pus and tissue swelling within the tooth. This causes a toothache. The toothache may stop if pressure is relieved. But the infection will remain active and continue to spread. This will cause more pain and can destroy tissue. Symptoms The main symptom is a severe toothache. The pain is continuous. It does not stop. It can be described as gnawing, sharp, shooting, or throbbing. Other symptoms may include: Bitter taste in the mouth Breath odor General discomfort, uneasiness, or ill feeling Fever Pain when chewing Sensitivity of the teeth to hot or cold Swelling of the gum over the infected tooth, which may look like a pimple Swollen glands of the neck Swollen area of the upper or lower jaw, which is a very serious symptom Exams and Tests Your dentist will closely look at your teeth, mouth, and gums. It may hurt when the dentist taps the tooth. Biting or closing your mouth tightly also increases the pain. Your gums may be swollen and red and may drain thick material. Dental x-rays and other tests can help your dentist determine which tooth or teeth are causing the problem. Treatment The goals of treatment are to cure the infection, save the tooth, and prevent complications. Your dentist might prescribe antibiotics to fight the infection. Warm saltwater rinses may help ease the pain. Over-the-counter pain relievers may relieve your toothache and fever. Do NOT place aspirin directly on your tooth or gums. This increases irritation of the tissues and can result in mouth ulcers. A root canal may be recommended in an attempt to save the tooth. If you have a severe infection, your tooth may need to be removed, or you may need surgery to drain the abscess. Some people may need to be admitted to the hospital. Outlook (Prognosis) Untreated abscesses may get worse and can lead to life-threatening complications. Prompt treatment cures the infection in most cases. The tooth can often be saved. Possible Complications These complications can occur: Loss of the tooth Blood infection Spread of infection to soft tissue Spread of infection to the jaw bone Spread of infection to other areas of the body, which can cause brain abscess, inflammation in the heart, pneumonia, or other complications When to Contact a Medical Professional Call your dentist if you have a throbbing toothache that does not go away, or if you notice a bubble (or "pimple") on your gums. Prevention Prompt treatment of dental decay reduces the risk of developing a tooth abscess. Have your dentist examine any broken or chipped teeth right away. Review Date 2/5/2018 Updated by: Ilona Fotek, DMD, MS, Dental Healing Arts, Jupiter, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. 

Answer: A tooth abscess is an infection in the center of the tooth caused by bacteria. The infection results in a buildup of pus and tissue swelling within the tooth, which causes a toothache. If the infection is not treated, it can continue to spread, which can cause loss of the tooth, blood infection, and spread of the infection to other areas of the body.