Lavespere J E, Yukna R A, Rice D A, LeBlanc D M
Periodontics Department, Louisiana State University School of Dentistry, New Orleans, USA.
J Periodontol. 1996 Dec;67(12):1281-7. doi: 10.1902/jop.1996.67.12.1281.
Adequate root preparation in periodontal procedures includes the removal of plaque, calculus, and perhaps contaminated cementum and dentin. The purpose of this study was to evaluate and compare the amount of root surface removal and residual surface texture using similarly shaped regular (US) and both fine (FINDIAM) and medium (MEDDIAM) grit diamond-coated ultrasonic inserts. Forty-five (45) premolars extracted for orthodontic reasons were randomly divided into 3 groups of 15 teeth each. They were individually mounted in a jig and instrumented with a standardized 500 gram force while they were moved a precise horizontal distance of 12 mm over a 1.2 second period using specially designed and computer controlled instrumentation. Three measurements were made to the nearest 0.0005" at 3 points along the test area before instrumentation and after 10 and 20 strokes. The mean depth of root structure removed was US 5.8 +/- 6.6 microns, FINDIAM 50.1 +/- 14.2 microns, MEDDIAM 30.8 +/- 12.1 microns, after 10 strokes, and US 12.7 +/- 10.9 microns, FINDIAM 83.3 +/- 20.1 microns, MEDDIAM 58.7 +/- 17.9 microns after 20 strokes, respectively. All 3 instruments were different from each other (P < 0.001) in the 10 stroke group, while in the 20 stroke group FINDIAM and MEDDIAM were different from US (P < 0.001), but not from each other. Only FINDIAM showed a significant difference between 10 and 20 stroke values for depth of root removal. Modified loss of tooth substance index SEM scores indicated increasingly greater root surface roughness from US to FINDIAM to MEDDIAM. Substantially greater root surface removal and greater residual root surface roughness occurred with diamond-coated ultrasonic inserts under standardized in vitro conditions. These results suggest that caution should be used with diamond-coated ultrasonic instruments during periodontal root planing procedures.
牙周治疗中充分的牙根预备包括去除菌斑、牙石，可能还包括受污染的牙骨质和牙本质。本研究的目的是评估和比较使用形状相似的常规（美国）以及细粒度（FINDIAM）和中粒度（MEDDIAM）金刚石涂层超声工作尖时牙根表面去除量和残留表面纹理。因正畸原因拔除的45颗前磨牙被随机分为3组，每组15颗牙。将它们分别安装在夹具中，并在使用专门设计的计算机控制仪器在1.2秒内精确水平移动12毫米的同时，施加标准化的500克力进行操作。在操作前以及操作10次和20次后，在测试区域沿三个点进行测量，精确到最接近的0.0005英寸。操作10次后，牙根结构去除的平均深度分别为：美国工作尖5.8±6.6微米，FINDIAM工作尖50.1±14.2微米，MEDDIAM工作尖30.8±12.1微米；操作20次后，分别为美国工作尖12.7±10.9微米，FINDIAM工作尖83.3±20.1微米，MEDDIAM工作尖58.7±17.9微米。在操作10次的组中，所有三种器械相互之间均有差异（P<0.001），而在操作20次的组中，FINDIAM和MEDDIAM与美国工作尖有差异（P<0.001），但它们彼此之间无差异。只有FINDIAM在操作10次和20次时牙根去除深度值之间存在显著差异。改良的牙体组织丧失指数扫描电镜评分表明，从美国工作尖到FINDIAM工作尖再到MEDDIAM工作尖，牙根表面粗糙度越来越大。在标准化体外条件下，金刚石涂层超声工作尖导致牙根表面去除量显著更大，残留牙根表面粗糙度也更大。这些结果表明，在牙周根面平整操作中使用金刚石涂层超声器械时应谨慎。
