Eisenburger M, Addy M
Department of Prosthetic Dentistry, Medical University of Hanover, Hanover, Germany.
J Dent. 2002 Sep-Nov;30(7-8):341-7. doi: 10.1016/s0300-5712(02)00048-9.
The aim of the study in vitro was to measure the interplay of attrition and erosion of human enamel under several different pH conditions.
Cusp and smooth surface enamel specimens were prepared from unerupted human third molar teeth. Cusp and smooth surface specimens opposed each other in a wear machine under a load of 600 g. The machine simulated tooth grinding for 30 min (2280 wear cycles). Six groups of 10 specimens were worn in the following environmental conditions: saline, citric acid at pH values of 3.2, 5.5 or 7.0 and two cycling groups (pH 3.2/saline or saline/pH 3.2). Additionally, 10 smooth surface specimens were exposed to the same fluids without attrition. Tissue loss on smooth surface specimens was determined by profilometry. The worn specimen surfaces were studied by SEM.
Attrition depth in saline and pH 7.0 citric acid was 25.5 microm. At pH 3.2 and 5.5 attrition depths were 6.0 and 4.3 microm, respectively. Cycling in saline/citric acid and vice versa produced attrition depths of 9.2 and 7.9 microm, respectively. In the erosion only specimens lesion depths were 3.0, 1.2 and 0 microm at pH 3.2, 5.5 and 7.0 and saline, respectively. Attrition specimens at pH 7.0 and in saline showed very rough surfaces. At low pH enamel surfaces appeared flat and smooth.
Enamel wear in neutral conditions is significantly higher than in acidic conditions (p < 0.05), apparently due to a smoothing effect of erosion on contacting surfaces.
本体外研究旨在测量在几种不同pH条件下人类牙釉质磨耗与侵蚀的相互作用。
从未萌出的人类第三磨牙制备牙尖和平滑面釉质标本。牙尖和平滑面标本在磨损试验机中相对，负载为600克。该机器模拟牙齿研磨30分钟（2280次磨损循环）。六组每组10个标本在以下环境条件下进行磨损：生理盐水、pH值为3.2、5.5或7.0的柠檬酸以及两个循环组（pH 3.2/生理盐水或生理盐水/pH 3.2）。此外，10个平滑面标本暴露于相同液体中但无磨耗。通过轮廓测定法确定平滑面标本的组织损失。通过扫描电子显微镜研究磨损标本表面。
在生理盐水和pH 7.0柠檬酸中磨耗深度为25.5微米。在pH 3.2和5.5时，磨耗深度分别为6.0和4.3微米。在生理盐水/柠檬酸以及反之的循环中，磨耗深度分别为9.2和7.9微米。在仅进行侵蚀的标本中，在pH 3.2、5.5和7.0以及生理盐水中的病变深度分别为3.0、1.2和0微米。pH 7.0和生理盐水中的磨耗标本表面非常粗糙。在低pH值下，牙釉质表面显得平坦光滑。
中性条件下的牙釉质磨损明显高于酸性条件（p < 0.05），显然是由于侵蚀对接触表面的平滑作用。
