Etman Maged K, Woolford Mark, Dunne Stephen
Division of Prosthodontics, College of Dentistry, University of Saskatchewan, Saskatoon, Canada.
Int J Prosthodont. 2008 May-Jun;21(3):245-52.
The aim of this study was to quantitatively measure tooth and ceramic wear over a 2-year period using a novel superimposition technique. Three ceramic systems--experimental hot-pressed ceramic (EC), Procera AllCeram (PA), and metal-ceramic--were used.
A total of 90 posterior crowns in 48 patients were randomized into 3 groups, and impressions were made at baseline and at 6-month intervals for 2 years. Clinical images were taken after using a dye to highlight surface changes. The impressions were digitized and modeled as superimposable 3-dimensional colored surface images. The depth of wear at the occlusal contact areas was quantitatively measured at 6, 12, 18, and 24 months.
The quantitative evaluation showed more wear in Procera AllCeram at the occlusal contact areas, whereas the experimental and metal-ceramic systems showed less wear. There was a significant difference in the amount of enamel worn between all types of restorations (P < .05). There was a statistically significant difference (P < .05) in the mean depth of wear between all systems.
The metal-ceramic and experimental systems showed less change, indicating improved wear resistance compared with Procera AllCeram. In addition, enamel opposing metal-ceramic and experimental crowns showed less wear compared to enamel opposed by Procera AIICeram crowns.
本研究的目的是使用一种新颖的叠加技术，对2年期间的牙齿和陶瓷磨损进行定量测量。使用了三种陶瓷系统——实验性热压陶瓷（EC）、Procera全瓷（PA）和金属陶瓷。
48例患者的90颗后牙冠被随机分为3组，在基线时以及之后2年每6个月取一次印模。使用染料突出表面变化后拍摄临床图像。将印模数字化，并建模为可叠加的三维彩色表面图像。在6、12、18和24个月时定量测量咬合接触区域的磨损深度。
定量评估显示，Procera全瓷在咬合接触区域的磨损更多，而实验性和金属陶瓷系统的磨损较少。所有类型修复体之间的牙釉质磨损量存在显著差异（P < .05）。所有系统之间的平均磨损深度存在统计学显著差异（P < .05）。
金属陶瓷和实验性系统的变化较小，表明与Procera全瓷相比，耐磨性有所提高。此外，与Procera全瓷冠相对的牙釉质相比，与金属陶瓷和实验性冠相对的牙釉质磨损较少。
