Chen C P, Yeh C L, Yang Y K, Ma C C, Nieh S
School of Dentistry, National Defense Medical Center, Taipei.
Zhonghua Ya Yi Xue Hui Za Zhi. 1990 Jun;9(2):51-60.
The purpose of this study was to compare the debridement efficacy of hand, sonic (MM-3000), and ultrasonic (Cavi-Endo) appliances, utilizing the same K-type files and a constant flow irrigation system, in the mesial root canals of extracted human mandibular 1st and 2nd molars. Only those roots with a canal curvature of between 10 and 30 degrees, by Schneider's method, were used in this study. The instrumentation time per mesial root canal for each treatment group was also evaluated. Following canal preparation and histological processing, the middle and apical cross-sections were examined to determine the percentage of canal and isthmus cleanliness, and the percentage of planed canal walls in the main canal area. Statistical analysis indicated no significant difference in canal and isthmus cleanliness at the middle and apical levels. All techniques achieved a high level of canal cleanliness. However, step-back hand instrumentation had the greatest percentage of planed canal walls in the main canal area at every portion of the root. Sonic instrumentation, in this study, was significantly faster than hand instrumentation in preparing the root canal system.
本研究的目的是比较在拔除的人类下颌第一和第二磨牙的近中根管中，使用相同的K型锉和恒定流量冲洗系统时，手动、声波（MM - 3000）和超声（Cavi - Endo）器械的清创效果。本研究仅使用通过施奈德方法测量根管弯曲度在10至30度之间的牙根。还评估了每个治疗组每个近中根管的操作时间。在根管预备和组织学处理后，检查中部和根尖横截面，以确定根管和峡部清洁度的百分比，以及主根管区域内根管壁平整的百分比。统计分析表明，在中部和根尖水平，根管和峡部清洁度没有显著差异。所有技术都达到了较高的根管清洁水平。然而，逐步后退式手动器械操作在牙根各部分的主根管区域内，根管壁平整的百分比最高。在本研究中，声波器械操作在根管系统预备方面明显比手动器械操作更快。
