1998 年 19 巻 2 号 p. 150-158
Abstract : The purpose of this study was to compare the working time and apical leakage of the lateral condensation method with those of continuous wave of obturation technique. One hundred and sixty-seven root canals of 60 human molars stored in distilled water were prepared using Profile .04 tapers driven by the Tri Auto ZX at manual mode in a crown down sequence. The teeth were divided into 4 groups after the root canal preparation was completed. Group 1 canals (n=41) obturated with the lateral condensation technique served as controls. Group 2 (n=43), 3 (n=40) and 4 (n=43) canals were obturated with continuous wave of obturation technique using the System B for down-packing and the Obtura Ⅱ for back-packing. In groups 2, 3 and 4, a nonstandardized master cone (Kerr), a standardized master cone (GC) and warmed gutta-percha injected by Obtura Ⅱ were used for down-packing, respectively. Tooth apices were immersed in india ink and cleared to measure the length of dye penetration. Each working time of 3 experimental groups (34.6, 36.2 and 37.0 seconds for group 2, 3 and 4, respectively) was significantly shorter than that of the control group (78.1 seconds, one way-ANOVA, p<0.05). No difference was found in dye leakage along the main canal among the four groups (0.60, 0.88, 0.98 and 0.91 mm for group 1, 2, 3 and 4, respectively, one way-ANOVA, p>0.05). The continuous wave of obturation technique using the System B and Obtura Ⅱ showed a satisfactory seal and shorter working time for the root canal obturation.
