Influence of calcium hydroxide on marginal leakage of endodontically treated teeth

Aim: To evaluate the influence of residual calcium hydroxide (CH) intracanal medication considering two dye leakage locations (apical foramen and middle root canal third) by quantifying the diffusion of India ink in length and depth.
Methods: After biomechanical preparation, 72 single-rooted bovine teeth were divided into two groups in which half was filled with a CH and saline paste. After 7 days, the medication was removed and the canals in both groups were filled. Half of the samples had the apical third and part of middle third removed for infiltration of India ink at the middle third (MTI), while the rest were infiltrated at the apical foramen (AI). The following experimental groups were formed (n = 18 each): A1 - CH-medicated + AI, A2 - CH-medicated + MTI, B1 - non-medicated + AI, B2 - non-medicated + MTI. For evaluation of dye leakage, the experimental specimens were cross-sectioned, photographed and had the infiltration perimeter measured using the Image Tool 3.00 software. The Mann-Whitney U-test was used for statistical analysis (p <0.05).
Results: The lowest values of dye penetration in length and depth were found in the groups receiving intracanal medication (A1 and A2).
Conclusions: Lower dye penetration in length and depth at the two different locations was observed in the canals with residual CH intracanal medication.