An apicoectomy is necessary when conventional root canal therapy has failed and a re-treatment was already unsuccessful or is not advised.

State-of-the-art procedures make use of microsurgical endodontic techniques, such as a dental operating microscope, micro instruments, ultrasonic preparation tips and calcium-silicate based filling materials.

It is beneficial if they are easy to handle, as they are placed in small amounts under technically demanding conditions, and if they are easily identified on radiographs (i.e.

Dentists are required to handle mercury very carefully and put mercury-based waste in special biohazard containers.

Composite resin is commonly used as a filling material due to its aesthetic qualities and ability to effectively bond to tooth structure, especially enamel.

It has proven very popular as a root-end filling material and has shown generally high success rates.

Studies generally focus on one material or method of treatment compared to another, so it can be difficult to obtain any good evidence on the overall success rate.