PDF(Pubmed)
Abstract：
Although advancements in CAD/CAM technology allow for more personalized treatments, it is not clear how modifications in the CAD/CAM milling process could affect the restoration surface conditions and their mechanical behavior. The objective of this study was to evaluate the effect of different CAD/CAM milling protocols on the topography and fracture behavior of zirconia monolithic crowns (3Y-PSZ) subjected to a chewing simulation. Monolithic 3Y-PSZ premolar crowns were milled using three protocols (n = 13) (slow (S), normal (N), and fast (F)). Crowns were cemented on a dentin analog abutment and subjected to mechanical aging (200 N, 2 Hz, 1,500,000 cycles, 37 °C water). Surviving crowns were subjected to compressive load test and analyzed using fractography. Fracture load data were analyzed with two-parameter Weibull analysis. The surface topography of the crowns was examined with a stereomicroscope and a 3D non-contact profiler. All crowns survived the chewing simulation. Crowns milled using the F protocol had the greatest characteristic fracture load, while crowns produced with the S protocol showed high Weibull modulus. Groups N and S had a more uniform surface and detailed occlusal anatomy than group F. The CAD/CAM milling protocol affected the topography and mechanical behavior of 3Y-PSZ monolithic crowns.
摘要：
尽管CAD/CAM技术的进步允许更个性化的治疗，目前尚不清楚CAD/CAM铣削过程中的修改如何影响修复表面条件及其力学行为。这项研究的目的是评估不同的CAD/CAM铣削方案对经受咀嚼模拟的氧化锆整体冠（3Y-PSZ）的形貌和断裂行为的影响。使用三种方案（n=13）（慢速（S），normal(N),和快速（F））。将牙冠粘合在牙本质模拟基台上，并进行机械老化（200N，2Hz,1,500,000次循环，37°C水)。对幸存的牙冠进行压缩载荷测试，并使用断口法分析。断裂载荷数据采用双参数威布尔分析。用立体显微镜和3D非接触式轮廓仪检查了牙冠的表面形貌。所有牙冠都在咀嚼模拟中幸存下来。使用F协议研磨的牙冠具有最大的特征断裂载荷，而用S方案生产的牙冠显示出高的威布尔模量。N组和S组比F组具有更均匀的表面和详细的咬合解剖结构。CAD/CAM铣削方案影响了3Y-PSZ整体式牙冠的形貌和力学行为。
