PDF(Pubmed)
Abstract：
OBJECTIVE: This study aimed to design a modified passive-deflation sealer injection needle and investigate its ability to improve obturation quality of single-cone technique through assessing the distribution of voids in root canals using micro-computed tomography (micro-CT).
METHODS: Forty-eight mandibular incisors were divided into eight groups (n = 6), according to the taper of root canal preparation (0.06 or 0.04), the needle used for sealer injection (modified or commercial iRoot SP injection needle), and the obturation method (iRoot SP sealer-only or single-cone obturation). After obturation, each specimen was scanned by micro-CT. The volumetric percentage and distribution of all voids were first analyzed and compared among groups, then the open and closed voids were separately analyzed and compared among single-cone obturation groups.
RESULTS: Compared to commercial needle groups, modified needle groups showed much less voids, especially in the apical root canal part (P < 0.05). Besides, the modified needle groups produced much less open voids than commercial needle groups despite the root canal taper (P < 0.05).
CONCLUSIONS: The modified passive deflation sealer injection needle could effectively improve the quality of single-cone obturation through reducing intra-canal voids, especially open voids throughout the root canal, thus might possibly be developed as an effective intra-canal sealer delivering instrument.
METHODS: Forty-eight mandibular incisors were divided into eight groups (n = 6), according to the taper of root canal preparation (0.06 or 0.04), the needle used for sealer injection (modified or commercial iRoot SP injection needle), and the obturation method (iRoot SP sealer-only or single-cone obturation). After obturation, each specimen was scanned by micro-CT. The volumetric percentage and distribution of all voids were first analyzed and compared among groups, then the open and closed voids were separately analyzed and compared among single-cone obturation groups.
RESULTS: Compared to commercial needle groups, modified needle groups showed much less voids, especially in the apical root canal part (P < 0.05). Besides, the modified needle groups produced much less open voids than commercial needle groups despite the root canal taper (P < 0.05).
CONCLUSIONS: The modified passive deflation sealer injection needle could effectively improve the quality of single-cone obturation through reducing intra-canal voids, especially open voids throughout the root canal, thus might possibly be developed as an effective intra-canal sealer delivering instrument.
摘要：
目的：本研究旨在设计一种改进的被动放气密封注射针，并通过使用微型计算机断层扫描（micro-CT）评估根管中空隙的分布，研究其改善单锥技术闭塞质量的能力。
方法：将48颗下颌切牙分为8组（n=6），根据根管预备的锥度（0.06或0.04），用于密封剂注射的针头（改装或商用iRootSP注射针），和封闭方法（仅iRootSP封闭或单锥封闭）。闭塞后，每个标本均采用micro-CT扫描.首先分析并比较各组间所有空隙的体积百分比和分布，然后分别分析和比较单锥体闭塞组之间的开口和闭合空隙。
结果：与商业针头组相比，改良的针组显示出更少的空隙，尤其是根尖部分(P<0.05)。此外,尽管根管逐渐变细，但改良针组产生的开口空隙比商业针组少得多（P<0.05）。
结论：改良的被动放气密封注射针通过减少管内空隙，可有效提高单锥闭塞的质量，尤其是整个根管的开放空隙，因此，可能被开发为一种有效的管内密封器输送器械。
方法：将48颗下颌切牙分为8组（n=6），根据根管预备的锥度（0.06或0.04），用于密封剂注射的针头（改装或商用iRootSP注射针），和封闭方法（仅iRootSP封闭或单锥封闭）。闭塞后，每个标本均采用micro-CT扫描.首先分析并比较各组间所有空隙的体积百分比和分布，然后分别分析和比较单锥体闭塞组之间的开口和闭合空隙。
结果：与商业针头组相比，改良的针组显示出更少的空隙，尤其是根尖部分(P<0.05)。此外,尽管根管逐渐变细，但改良针组产生的开口空隙比商业针组少得多（P<0.05）。
结论：改良的被动放气密封注射针通过减少管内空隙，可有效提高单锥闭塞的质量，尤其是整个根管的开放空隙，因此，可能被开发为一种有效的管内密封器输送器械。
