The cause of pain can be deep tooth decay or filling if the tooth is alive or a granuloma or abscess if the tooth is dead (these are teeth that do not have a nerve, they turn gray and burst). If the cause of the pain is tooth decay, then over time it spreads to the nerve and infects the area in which it is located. A damaged nerve can react with inflammation that you will surely feel, or with decay that can go away without symptoms.
Root canal treatment is an endodontic procedure that treats a problematic tooth. Machine endodontics is a more modern approach to dental treatment and we are usually faster and more efficient with it. We start the treatment with anesthesia, followed by an opening where we reach the nerve. There are two possible ways to go from there.