Materials and methods: For background literature, an electronic search was conducted in PubMed. Key words related to apicoectomy, root-end filling materials and micro leakage were used. Apart from PubMed, the web pages of the manufactures were used to include the information that only has been published in the form abstract or being just “data on file” without any other forum of publication. Simultaneously dye micro leakage lab experiments were conducted, testing Biodentine™, IRM® and ProRoot MTA™ as root-end fillings. The experiments were performed using extracted human teeth and fuchsin-colored dye solution. The experimental protocol was compiled using well-known principles with references. A total of three experiments were performed; a pilot experiment (Experiment 1), Experiment 2 and Experiment 3.The pilot experiment (Experiment 1) aimed to evaluate the feasibility of the dye leakage experiment for ex vivo teeth. The results of the pilot experiment were used as a guideline for the dye leakage experiment in Experiment 2. In Experiment 3 ProRoot MTA™ was used as root-end fillings as a standard to investigate dye leakage after different immersion times.

Results: In Experiment 1, two out of five canals filled with Biodentine™ could resist dye penetration. None of the canals filled with ProRoot MTA™ or IRM® resisted dye penetration. In Experiment 2 only one canal filled with ProRoot MTA resisted dye penetration. Biodentine™ and IRM® displayed total leakage through the root-end filling material. However, the specimens with Biodentine™ had less leakage through the gutta-percha compared to IRM®. In Experiment 3 total dye leakage was not seen in specimens immersed in a 1- to 3-hour time frame. Total leakage of the root-end filling was first seen after 6 hours. After 12 hours, dye had penetrated both the root-end filling and the gutta-percha.

Conclusion: In Experiment 2, ProRoot MTA™ was the only material to resist apical leakage. The proper dye immersion time was established in Experiment 3, using MTA samples only. The experiment should now be repeated in order to establish the ability of Biodentine™ to resist apical leakage compared to ProRoot MTA™.

Aim and hypothesis: The purpose of this study is to evaluate Biodentine™ as a root-end filling. The working hypothesis is that Biodentine™ provides apical bacterial seal as MTA when applied in root-end filling therapy.