Post and core restoration has been widely used in clinic for a large amount loss of teeth. As the first step of this restoration, post space preparation plays an important role in the apical sealing ability. Immediate or delayed preparation, the amount of root canal filling remaining, gutta-percha removal techniques and obturation techniques used have been the subjects of investigation on it. Microleakage is considered to be a key indicator in assessing the apical ability. Several methods for testing apical leakage have also been introduced, such as using dyes, fluid filtration or transport methodology, bacteria and toxin infiltration method. General studies regarding the apical sealing of post space preparation and methodologies for assessment will be discussed in this review.
