All teeth are held firmly in place by strong roots extending into the jawbone. Front incisors only have a single root, while molars and premolars normally have several roots. The apex is the end or tip of each root, where nerves and blood vessels enter the tooth and aid in the delivery of blood to the visible part of the tooth.
An apicoectomy is a procedure where the apex or root tip is essentially removed and is followed by a filling procedure that seals the root from further infection, because infected roots can damage other teeth, spread infection and cause regression of the jawbone if left untreated. After a root canal treatment, which cleans the canals and removes infected and inflamed tissue in the root, an apicoectomy may be required when the inflammation or infection persists after root canal treatment.