Once a healthy tooth becomes heavily decayed or cracked, there is a possibility that bacteria can invade the tooth and access the nerve inside. When the bacteria infect the nerve, the tooth starts to die. This may present as a toothache or the tooth may be sore to chew on.
Traditionally these teeth were extracted, however, root canal treatment can save the tooth by removing this infected tissue, and filling up the void inside the tooth where the nerve used to be.
Root treated teeth tend to be very brittle, so we highly recommend having a crown or onlay restoration to strengthen and protect the weakened tooth after the treatment is completed.