Résumé
Non-reinforced ZOE is the substance that is commonly used in pulpectomy and filling primary teeth canals. Two different ways may be used plugger or lentulo spiral to carry ZOE into the canals. The aim of this study was to compare the degree of microleakage in pulpectomy of primary teeth with each of these two different ways. In this experimental study, 44 single rooted primary teeth from maxilla were used based on convenience sampling. First, pulps of all the teeth were removed and all of them were filed. Then all the samples were divided into four groups randomly, two experimental groups each with 20 cases and two smaller groups each with only 2 cases as positive and negative control. In the first experimental group, dental canals were obturated with a thick mix of pure ZOE through condensing with plugger manually. In the second experimental group, dental canals were obturated with a thin mix of ZOE by lentulo spiral. Coronal end of the canals were sealed with Coltosol and most of the root surface was covered with two layers of nail polish and one layer of stick wax, except for 2 mm of apical end of the root. Then samples were immersed in 2% methylene blue and sectioned longitudinally. Finally dye penetration was calculated under a stereomicroscope and results were analyzed by t-test. The mean value of dye penetration [microleakage] in first group was 2.92 mm and for the second group was about 4.83 mm so that the mean value in the first group was significantly lesser than that of the second group [P<0.001]. Because of high viscosity and thickness of ZOE, the hand-held technique [using plugger] had lesser microleakage and better apical seal which could be considered as the preferred technique in filling primary teeth canals