Yoo Jun Sang, Chang Seok-Woo, Oh So Ram, Perinpanayagam Hiran, Lim Sang-Min, Yoo Yeon-Jee, Oh Yeo-Rok, Woo Sang-Bin, Han Seung-Hyun, Zhu Qiang, Kum Kee-Yeon
Department of Dentistry, U Dental Hospital, Seoul, Korea.
Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, Seoul, Korea.
Int J Oral Sci. 2014 Dec;6(4):227-32. doi: 10.1038/ijos.2014.30. Epub 2014 Jul 11.
The time domain entombment of bacteria by intratubular mineralization following orthograde canal obturation with mineral trioxide aggregate (MTA) was studied by scanning electron microscopy (SEM). Single-rooted human premolars (n=60) were instrumented to an apical size #50/0.06 using ProFile and treated as follows: Group 1 (n=10) was filled with phosphate buffered saline (PBS); Group 2 (n=10) was incubated with Enterococcus faecalis for 3 weeks, and then filled with PBS; Group 3 (n=20) was obturated orthograde with a paste of OrthoMTA (BioMTA, Seoul, Korea) and PBS; and Group 4 (n=20) was incubated with E. faecalis for 3 weeks and then obturated with OrthoMTA-PBS paste. Following their treatments, the coronal openings were sealed with PBS-soaked cotton and intermediate restorative material (IRM), and the roots were then stored in PBS for 1, 2, 4, 8 or 16 weeks. After each incubation period, the roots were split and their dentin/MTA interfaces examined in both longitudinal and horizontal directions by SEM. There appeared to be an increase in intratubular mineralization over time in the OrthoMTA-filled roots (Groups 3 and 4). Furthermore, there was a gradual entombment of bacteria within the dentinal tubules in the E. faecalis inoculated MTA-filled roots (Group 4). Therefore, the orthograde obturation of root canals with OrthoMTA mixed with PBS may create a favorable environment for bacterial entombment by intratubular mineralization.
通过扫描电子显微镜（SEM）研究了用三氧化矿物凝聚体（MTA）进行根管正向充填后，细菌在管内矿化作用下的时域包埋情况。使用Profile将60颗单根人前磨牙预备至根尖尺寸#50/0.06，并按以下方式处理：第1组（n = 10）用磷酸盐缓冲盐水（PBS）充填；第2组（n = 10）与粪肠球菌孵育3周，然后用PBS充填；第3组（n = 20）用OrthoMTA（韩国首尔BioMTA公司）糊剂和PBS进行正向充填；第4组（n = 20）与粪肠球菌孵育3周，然后用OrthoMTA-PBS糊剂充填。处理后，用浸有PBS的棉球和中间修复材料（IRM）封闭冠部开口，然后将牙根置于PBS中保存1、2、4、8或16周。在每个孵育期后，将牙根劈开，通过SEM在纵向和横向两个方向检查牙本质/MTA界面。在充填OrthoMTA的牙根（第3组和第4组）中，管内矿化似乎随时间增加。此外，在接种粪肠球菌的MTA充填牙根（第4组）的牙本质小管内，细菌逐渐被包埋。因此，用OrthoMTA与PBS混合进行根管正向充填可能为管内矿化包埋细菌创造有利环境。
