Coelho Marcelo Santos, Card Steven J, Tawil Peter Z
Department of Endodontics, UNC School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Department of Endodontics, UNC School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
J Endod. 2016 Jul;42(7):1110-3. doi: 10.1016/j.joen.2016.04.006. Epub 2016 May 10.
Several recent studies have evaluated the presence of dentinal defects after root canal preparation in extracted human teeth by using the root sectioning methodology. The objective of this research was to investigate whether light-emitting diode (LED) transillumination enhances the visualization of dentinal defects by using a root sectioning methodology.
Forty mesial roots of mandibular molars were sectioned at 3, 6, and 9 mm from the apex with a low-speed saw under water cooling. Microscopic pictures of the specimens were taken by using ×19.2 magnification for the 3-mm slice and ×12.8 magnification for the 6- and 9-mm slices. The LED transillumination was done by positioning an LED probe at 4 different locations (mesial, distal, buccal, and lingual). The root canal lumen was masked, and 2 independent evaluators assessed the presence of dentinal defects on the non-LED and LED images. The number of dentinal defects was recorded, and χ(2) test was used for statistical analysis (P < .05).
The number of slices presenting dentinal defects at 3, 6, and 9 mm were 2 (5%), 1 (2.5%), and 1 (2.5%), respectively, for the non-LED assessment and 8 (20%), 10 (25%), and 9 (22.5%), respectively, for the LED assessment. Overall, 4 of the specimens (10%) presented dentinal defects without LED evaluation, and 19 of the specimens (47.5%) presented dentinal defects with LED evaluation. This difference was statistically significant (P < .05).
LED transillumination enhanced the visualization of dentinal defects in uninstrumented roots. The results from previous studies that used the traditional non-LED sectioning methodology should be evaluated with caution.
最近有几项研究通过牙根切片法评估了拔除的人牙在根管预备后牙本质缺陷的存在情况。本研究的目的是通过牙根切片法研究发光二极管（LED）透照是否能增强牙本质缺陷的可视化。
在下颌磨牙的40个近中根上，于根尖3、6和9毫米处使用低速锯在水冷条件下进行切片。对标本拍摄微观照片，3毫米切片使用×19.2倍放大，6毫米和9毫米切片使用×12.8倍放大。通过将LED探头放置在4个不同位置（近中、远中、颊侧和舌侧）进行LED透照。根管腔被遮挡，2名独立评估者在非LED和LED图像上评估牙本质缺陷的存在情况。记录牙本质缺陷的数量，并使用χ(2)检验进行统计分析（P < 0.05）。
在非LED评估中，3、6和9毫米处出现牙本质缺陷的切片数量分别为2（5%）、1（2.5%）和1（2.5%），而在LED评估中分别为8（20%）、10（25%）和9（22.5%）。总体而言，4个标本（10%）在未进行LED评估时出现牙本质缺陷，19个标本（47.5%）在进行LED评估时出现牙本质缺陷。这种差异具有统计学意义（P < 0.05）。
LED透照增强了未预备根管中牙本质缺陷的可视化。应谨慎评估先前使用传统非LED切片法的研究结果。
