Document Type: Original Article


1 Dept. of Endodontics, School of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran

2 Dentist, Private practice, Tabriz, Iran


Statement of Problem: Commonly, calcium hydroxide is used as an intra-canal dressing for disinfection and accelerating the repair of periapical lesions.Purpose: The purpose of this study was to determine the effect of using calcium hydroxide as an intra-canal medicament on apical seal.Materials and Method: In this experimental study, total of 60 one-rooted extracted human central incisors were instrumented with step-back technique. K-file (No 35) was selected as master apical file and flaring was done up to # 60. The teeth were randomly divided into two experimental each containing 20 teeth and two control groups each containing 10 teeth. In one experimental group, the root canals were filled with calcium hydroxide. After one week, the paste was removed using #35 K-file and normal saline irrigation. The root canals of experimental and negative control groups were obturated with gutta percha and AH 26 sealer using lateral condensation technique. In the positive control group the root canals were not obturated. Dye penetration technique was used for evaluating the rate of longitudinal microleakage. Dye penetration was measured by a milimetric ruler under stereomicroscope. For statistical analysis, Mann-Whitney test was used.Results:The results showed that there was no significant difference in apical microleakage between experimental groups ( p< 0.05).Conclusion: Using calcium hydroxide as an intra-canal medicament has no negative effect on apical seal. Further leakage studies are suggested to confirm the results of the present study.Key Words: Calcium hydroxide, Tooth apex, Seal, Dye, Root canal therapy