AIM: To investigate the microleakage of two different root canal obturation systems, using the nuclear medicine approach.METHODS: Twenty-six single-rooted extracted teeth were selected. The crowns were sectioned to ob...AIM: To investigate the microleakage of two different root canal obturation systems, using the nuclear medicine approach.METHODS: Twenty-six single-rooted extracted teeth were selected. The crowns were sectioned to obtain 15-mm long root segments and each tooth was prepared using rotary Pro File instruments. The roots were divided into 2 experimental groups using Real Seal 1 and Real Seal sealer or Thermafil and Top Seal sealer as well as two control groups. On the 7th and the 28 th day the apices were submersed in a solution of 99 m TcPertechnetate during 3 h. The radioactivity was counted using a γ camera. RESULTS: The present study showed that none of the root canal-filled teeth was leakage free. The statistical analyses were made using Kruskal-Wallis and statistical significance was assessed using α = 0.05. Although apical leakage measured in counts per minute(cpm) in the Thermafil/Top Seal group was lower than in the Real Seal/Real Seal group(363 916 ± 180 707.7 cpm vs533 427 ± 414 020.6 cpm) on 7th day and(1 678 200 ± 567 217.4 cpm vs 2 240 518 ± 383 356.7 cpm) on 28 th day, there was no statistical difference(P > 0.05). In the Thermafil/Top Seal group and Real Seal 1/Real Seal group it was found that over time, the number of counts increased between 7 d and 28 d(363 916 ± 180 707.7 cpm vs 1 678 200 ± 567 217.4 cpm) and(533 427 ± 414 020.6 cpm vs 2 240 518 ± 383 356.7 cpm), respectively, with statistically significant differences(Thermafil/Top Seal group, P = 0.015 and Real Seal 1/Real Seal group, P = 0.036).CONCLUSION:Both carrier-based Realseal 1 and Thermafil techniques showed a similar sealing effect,but none of the materials was leakage free.展开更多
This study investigated the microleakage of two different root canal obturation systems, using the nuclear medicine approach, with sodium pertechnetate 99mTc. Twenty six single-rooted extracted teeth were selected. Th...This study investigated the microleakage of two different root canal obturation systems, using the nuclear medicine approach, with sodium pertechnetate 99mTc. Twenty six single-rooted extracted teeth were selected. The crowns were sectioned to obtain15 mmlong root segments and each tooth was prepared using rotary ProFile? instruments. The roots were divided into 2 experimental groups and two control groups. Twenty root canals were filled, using Thermafil? and Topseal? or MTA Fillapex? as a sealer. On the 7th and the 28th day the apices were submersed in a solution of 99mTc-Pertechnetate during 3 hours. The radioactivity was counted using a gamma camera. Although apical leakage on the 7th day in the Topseal group was reduced compared with RealSeal1, with a statistical significant difference (p = 0.057), on the 28th day, the MTA Fillapex increased the sealing properties (p = 0.017).展开更多
The pullback attractors for the 2D nonautonomous g-Navier-Stokes equations with linear dampness axe investigated on some unbounded domains. The existence of the pullback attractors is proved by verifying the existence...The pullback attractors for the 2D nonautonomous g-Navier-Stokes equations with linear dampness axe investigated on some unbounded domains. The existence of the pullback attractors is proved by verifying the existence of pullback D-absorbing sets with cocycle and obtaining the pullback :D-asymptotic compactness. Furthermore, the estimation of the fractal dimensions for the 2D g-Navier-Stokes equations is given.展开更多
文摘AIM: To investigate the microleakage of two different root canal obturation systems, using the nuclear medicine approach.METHODS: Twenty-six single-rooted extracted teeth were selected. The crowns were sectioned to obtain 15-mm long root segments and each tooth was prepared using rotary Pro File instruments. The roots were divided into 2 experimental groups using Real Seal 1 and Real Seal sealer or Thermafil and Top Seal sealer as well as two control groups. On the 7th and the 28 th day the apices were submersed in a solution of 99 m TcPertechnetate during 3 h. The radioactivity was counted using a γ camera. RESULTS: The present study showed that none of the root canal-filled teeth was leakage free. The statistical analyses were made using Kruskal-Wallis and statistical significance was assessed using α = 0.05. Although apical leakage measured in counts per minute(cpm) in the Thermafil/Top Seal group was lower than in the Real Seal/Real Seal group(363 916 ± 180 707.7 cpm vs533 427 ± 414 020.6 cpm) on 7th day and(1 678 200 ± 567 217.4 cpm vs 2 240 518 ± 383 356.7 cpm) on 28 th day, there was no statistical difference(P > 0.05). In the Thermafil/Top Seal group and Real Seal 1/Real Seal group it was found that over time, the number of counts increased between 7 d and 28 d(363 916 ± 180 707.7 cpm vs 1 678 200 ± 567 217.4 cpm) and(533 427 ± 414 020.6 cpm vs 2 240 518 ± 383 356.7 cpm), respectively, with statistically significant differences(Thermafil/Top Seal group, P = 0.015 and Real Seal 1/Real Seal group, P = 0.036).CONCLUSION:Both carrier-based Realseal 1 and Thermafil techniques showed a similar sealing effect,but none of the materials was leakage free.
文摘This study investigated the microleakage of two different root canal obturation systems, using the nuclear medicine approach, with sodium pertechnetate 99mTc. Twenty six single-rooted extracted teeth were selected. The crowns were sectioned to obtain15 mmlong root segments and each tooth was prepared using rotary ProFile? instruments. The roots were divided into 2 experimental groups and two control groups. Twenty root canals were filled, using Thermafil? and Topseal? or MTA Fillapex? as a sealer. On the 7th and the 28th day the apices were submersed in a solution of 99mTc-Pertechnetate during 3 hours. The radioactivity was counted using a gamma camera. Although apical leakage on the 7th day in the Topseal group was reduced compared with RealSeal1, with a statistical significant difference (p = 0.057), on the 28th day, the MTA Fillapex increased the sealing properties (p = 0.017).
基金supported by the National Natural Science Foundation of China (No.10871156)the Fund of Xi'an Jiaotong University (No.2009xjtujc30)
文摘The pullback attractors for the 2D nonautonomous g-Navier-Stokes equations with linear dampness axe investigated on some unbounded domains. The existence of the pullback attractors is proved by verifying the existence of pullback D-absorbing sets with cocycle and obtaining the pullback :D-asymptotic compactness. Furthermore, the estimation of the fractal dimensions for the 2D g-Navier-Stokes equations is given.