Although permanent teeth were meant to last a lifetime, there are a number of reasons why tooth extraction may be needed. A very common reason involves a tooth that is too badly damaged, from trauma or decay, to be repaired.
Other reasons include:
A crowded mouth. Sometimes dentists pull teeth to prepare the mouth in order to properly align the teeth, which may not be possible if your teeth are too big for your mouth. Likewise, if a tooth cannot break through the gum because there is not room in the mouth for it, your dentist may recommend pulling it out.
Infection. If tooth decay or damage extends to the pulp (the centre of the tooth containing nerves and blood vessels) bacteria in the mouth can enter this area, leading to infection. Often this can be corrected with root canal therapy, but if the infection is so severe that antibiotics or root canal do not cure it, extraction may be needed to prevent the spread of infection.
Gum Disease is present. If an infection of the tissues and bones that surround and support the teeth have caused loosening of the teeth, it may be necessary to the pull the tooth or teeth out.