The term "root canal" is used to identify the natural cavity in the teeth where the soft area called porridge or pup chamber is found. The dental nerve whose sensory functions can also be found in the root canal. If the porridge is injured (repetitive dental procedures, patches, teeth are cracked or broken) or infected (due to tooth decay), pulp tissue and dead nerves that can severe infections when bacteria begin to multiply and must be removed. If you are looking for the root canal treatment then you can pop over the link.
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If not treated, the surrounding tissue may also be infected which will produce as follows: teeth abscess, bone loss around the root end, swelling may spread to the face, neck, or head, and the occurrence of a hole in the side of the teeth that can cause drainage problems to the gums , Cheeks, or skin.
However, unlike in the old days when a tooth had to be removed when it became infected, there is a special procedure nowadays called root canal or endodontic treatment where a tooth can be saved from extraction. Root canal therapy involves repairing and saving teeth that are infected badly by removing pulp and nerves and then protect it by cleaning and sealing the inside of the teeth. The crown is then placed on the teeth treated to make it stronger.