Faculty of Dentistry, Dental Research Institute, University of Toronto, Toronto, ON, Canada.
Int Endod J. 2018 Oct;51(10):1171-1180. doi: 10.1111/iej.12925. Epub 2018 Apr 19.
To evaluate the functional strain distribution pattern in root dentine following canal preparation and root canal surface engineering with crosslinked biopolymeric nanoparticles using digital moiré interferometry (DMI).
Root dentine specimens were prepared, grating material replicated and tested for 10-50 N, compressive loads in a customized high-resolution, whole-field moiré interferometry set-up. Digital moiré fringes were acquired to determine the strain distribution pattern at specific regions of interest before and after canal enlargement, and dentine surface engineering with a chitosan nanoparticle crosslinker solution. Fringe patterns were acquired, and strain distribution pattern in the direction perpendicular to dentinal tubules (U-field) and parallel to dentinal tubules (V-field) was analysed with custom digital image-processing software. Data were analysed with a statistical method on trend analysis at 0.05 significant level.
Distinct deformation patterns perpendicular to the dentinal tubules were observed in root dentine. Root canal dentine removal following instrumentation resulted in an increase in strain distribution, which increased with an increase in applied loads (P < 0.01). The root canal dentine engineered with crosslinked nanoparticles demonstrated a conspicuous decrease in previously increased strain distribution in both coronal and apical root dentine (P < 0.01). A significant increase in tensile strain in root dentine was observed subsequent to instrumentation in the direction parallel to dentinal tubules (P < 0.01). There was a significant reduction in the tensile strain formed at the apical region of the instrumented root dentine following crosslinked nanoparticle treatment (P < 0.05).
This study highlighted the potential of root canal dentine microtissue engineering with crosslinked chitosan nanoparticle to improve radicular strain distribution patterns in instrumented canals.
使用数字云纹干涉法(DMI)评估交联生物聚合纳米颗粒进行根管预备和根管表面工程后牙本质根部的功能应变分布模式。
制备根牙本质标本,复制光栅材料,并在定制的高分辨率全场云纹干涉装置中测试 10-50 N 的压缩载荷。在根管扩大和壳聚糖纳米颗粒交联剂溶液进行牙本质表面工程前后,获取数字云纹条纹以确定特定感兴趣区域的应变分布模式。使用定制的数字图像处理软件获取条纹图案,并分析与牙本质小管垂直(U 场)和与牙本质小管平行(V 场)的应变分布模式。使用具有趋势分析的统计方法在 0.05 的显著水平下分析数据。
在根牙本质中观察到与牙本质小管垂直的明显变形模式。器械处理后根管牙本质去除导致应变分布增加,随着施加的载荷增加而增加(P < 0.01)。用交联纳米粒子处理的根管牙本质在根管牙本质的冠部和根尖部都表现出明显减少的先前增加的应变分布(P < 0.01)。在与牙本质小管平行的方向上,器械处理后根牙本质的拉伸应变显著增加(P < 0.01)。交联纳米粒子处理后,器械处理的根牙本质根尖区形成的拉伸应变显著减少(P < 0.05)。
本研究强调了交联壳聚糖纳米颗粒的根管牙本质微组织工程在改善器械根管中根牙本质应变分布模式方面的潜力。