Ultrasonic irrigation flows in root canals: effects of ultrasound power and file insertion depth
Ultrasonic irrigation flows in root canals: effects of ultrasound power and file insertion depth
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DOI：
10.1038/s41598-024-54611-x
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发表时间：
2024-03-04
影响因子：
4.6
通讯作者：
Balabani，S.
中科院分区：
文献类型：
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作者：
Koulogiannis，A.;Walmsley，A. D.;Balabani，S.
根管治疗过程中的超声波冲洗可以增强生物膜的破坏。挑战在于改善流体流动，使得冲洗液到达手动仪器无法到达的区域。本研究的目的是实验研究如何超声冲洗引起的流场和流体动力的超声功率和文件插入深度的影响。3D打印根管体模并用作制造PDMS通道的模具。使用带有#15K锉的超声器械进行冲洗。利用粒子图像测速仪（PIV）对流场进行了研究。发现时间平均速度和剪切应力分布随超声功率显著变化。它们的最大值在低功率和达到临界功率水平时急剧增加。在此设置和以上，流动模式的变化，从高速度和剪切应力区限制在附近的尖端，一个覆盖整个根管域。超过这个阈值也会导致最大速度和剪切应力的适度增加。插入深度被发现有一个较小的影响上测得的速度和剪切应力。由于流动的振荡性质，瞬时最大速度和剪切应力可以达到比平均值高得多的值，特别是对于高功率。超声冲洗将受益于使用更高的功率设置，因为这确实会在根管壁附近产生更大的剪切应力，从而可能增加生物膜的去除。
Ultrasonic irrigation during root canal treatment can enhance biofilm disruption. The challenge is to improve the fluid flow so that the irrigant reaches areas inaccessible to hand instrumentation. The aim of this study is to experimentally investigate how the flow field and hydrodynamic forces induced by ultrasonic irrigation are influenced by the ultrasound power and file insertion depth. A root canal phantom was 3D printed and used as a mold for the fabrication of a PDMS channel. An ultrasonic instrument with a #15K-file provided the irrigation. The flow field was studied by means of Particle Image Velocimetry (PIV). The time averaged velocity and shear stress distributions were found to vary significantly with ultrasound power. Their maximum values increase sharply for low powers and up to a critical power level. At and above this setting, the flow pattern changes, from the high velocity and shear stress region confined in the vicinity of the tip, to one covering the whole root canal domain. Exceeding this threshold also induces a moderate increase in the maximum velocities and shear stresses. The insertion depth was found to have a smaller effect on the measured velocity and shear stresses. Due to the oscillating nature of the flow, instantaneous maximum velocities and shear stresses can reach much higher values than the mean, especially for high powers. Ultrasonic irrigation will benefit from using a higher power setting as this does produce greater shear stresses near the walls of the root canal leading to the potential for increased biofilm removal.