METHODS: Human maxillary incisors were randomly divided for instrumentation with one of the assayed systems. Canal shaping ability and pericervical dentin preservation were characterized through microtomographic evaluation and morphometric assessment (n = 15). Smear layer removal ability was evaluated by scanning electron microscopy (SEM) (n = 6).
RESULTS: TN and PU presented the lowest canal volume variation upon instrumentation, found to be significantly lower than that attained with WOG (P < .05). Pericervical dentin was reduced in all groups upon instrumentation, with TN evidencing the highest preservation, quantitatively similar to PU, and significantly higher than that attained with WOG (P < .05). SEM imaging revealed the presence of scattered remnants of the smear layer and partially opened dentinal tubules at the apical portion, with no significant differences between systems.
CONCLUSIONS: TN and PU allowed for the highest tissue preservation, reporting the lowest volume variation and the highest preservation of the pericervical dentin. None of the assessed systems provided a complete removal of the smear layer in the apical region.
方法:将人上颌切牙随机分为一个测定系统。通过显微层析成像评估和形态测量评估(n=15)来表征管道成形能力和宫颈牙本质保存。通过扫描电子显微镜(n=6)评价了涂抹层去除能力。
结果:TN和PU在仪器上表现出最低的运河容积变化,发现显著低于WOG(p<0.05)。所有组的子宫颈牙本质在器械上都减少了,TN证明了最高的保存,定量上与PU相似,显著高于WOG(p<0.05)。SEM成像显示,在根尖部分存在涂片层的分散残留物和部分开放的牙本质小管,系统之间没有显著差异。
结论:TN和PU允许最高的组织保存,报告最低体积变化和最高保存的子宫颈牙本质。评估的系统均未完全去除顶端区域的涂片层。