Department of Prosthodontics, Bharati Vidyapeeeth University Dental College and Hospital, Pune, Maharastra, India.
J Prosthodont. 2010 Apr;19(3):212-7. doi: 10.1111/j.1532-849X.2009.00559.x. Epub 2010 Jan 22.
This study was conducted to determine the abrasive effect of a porcelain and an Ni-Cr alloy on the wear of human enamel, and the influence of a carbonated beverage on the rate of wear.
Tooth specimens were prepared by embedding 48 freshly extracted mandibular first premolars in acrylic. Twenty-four of these specimens were abraded against Ni-Cr, and the remaining 24 against porcelain in artificial saliva and carbonated beverage media, respectively (n = 12), on a specially designed abrasive testing machine at a constant load of 40 N with 6 mm amplitude for 15,000 cycles. The cusp heights of the tooth specimens were measured both before and after abrasion using a profile projector. The abraded cast specimens were subjected to profilometry for computing the surface roughness; the abrading media was subjected to atomic absorption spectrophotometry for analyzing Ni and Cr ion levels. Data obtained were statistically analyzed.
Porcelain specimens in a medium of carbonated beverage caused the highest wear of tooth specimens. The lowest wear of tooth specimens was Ni-Cr specimens in artificial saliva medium. Carbonated beverage caused significantly higher wear of tooth specimens when abraded against Ni-Cr and porcelain specimens than did artificial saliva. The mean quantitative surface roughness of porcelain specimens was significantly higher than that of Ni-Cr specimens, irrespective of the medium in which abrasion testing was conducted. There was no statistically significant difference between the concentrations of Ni ions released in artificial saliva and carbonated beverage media. Also, there was no statistically significant difference between the concentrations of Cr ions released in artificial saliva and carbonated beverage media.
The wear of human enamel was significantly higher in the presence of carbonated beverage than artificial saliva and against porcelain when compared with Ni-Cr. The surface roughness of porcelain in the presence of carbonated beverage was found to be highest, and the release of Ni and Cr was not affected by carbonated beverage.
本研究旨在确定瓷和镍铬合金对人牙釉质磨损的磨损效果，以及碳酸饮料对磨损速率的影响。
通过将 48 颗刚从下颌第一前磨牙中提取的牙齿样本嵌入丙烯酸中，制备牙样本。其中 24 个样本在人工唾液和碳酸饮料介质中分别与镍铬合金（n = 12）、瓷进行磨损，在专门设计的磨损试验机上，以 40 N 的恒定载荷和 6 毫米的振幅进行 15000 次循环。使用轮廓投影仪测量牙样本磨损前后的牙尖高度。对磨损的铸样进行轮廓测量以计算表面粗糙度；对磨损介质进行原子吸收分光光度法分析镍和铬离子水平。对获得的数据进行统计学分析。
碳酸饮料介质中的瓷样本导致牙样本磨损最严重。人工唾液介质中的镍铬合金样本导致牙样本磨损最小。碳酸饮料导致与镍铬合金和瓷样本相比，人工唾液介质中牙样本的磨损明显增加。无论在哪个介质中进行磨损测试，瓷样本的平均定量表面粗糙度均明显高于镍铬合金样本。在人工唾液和碳酸饮料介质中，释放的镍离子浓度无统计学差异。同样，在人工唾液和碳酸饮料介质中，释放的铬离子浓度也无统计学差异。
与镍铬合金相比，碳酸饮料存在时牙釉质的磨损明显增加，与瓷相比时磨损增加。碳酸饮料存在时，瓷的表面粗糙度最高，且镍和铬的释放不受碳酸饮料的影响。
