College of Dentistry, Taibah University, Kingdom of Saudi Arabia, Taibah University, Kingdom of Saudi Arabia.
J Prosthet Dent. 2012 Dec;108(6):386-93. doi: 10.1016/S0022-3913(12)60198-X.
Fracture of feldspathic porcelain laminate veneers represents a significant mode of clinical failure. Therefore, ceramic materials that withstand a higher load to fracture, especially for patients with parafunctional habits, are needed.
The purpose of this study was to examine the correlation of material (zirconia, TZP, glass-ceramic, IEC, and feldspathic porcelain, FP) design (incisal overlapped preparation, IOP, and three-quarter preparation, TQP), and fracture mode to failure load for veneers supported by composite resin abutments.
A typodont tooth prepared with 2 designs (IOP, TQP) and the corresponding 2 definitive dies were used to fabricate the composite resin abutments (30 for IOP and 30 for TQP). Ten veneer specimens for each system (Y-TZP, IEC, and FP), were fabricated for each design. The veneers were cemented, invested, and tested in compression until failure by using a universal testing machine. Significant differences were evaluated by 2-factor ANOVA (α=.05).
No statistical mean load difference was noted between the preparation designs for Y-TZP (IOP: 244 ±81 and TQP: 224 ±58 N), IEC (IOP: 306 ±101 and TQP: 263 ±77 N), and FP veneers (IOP: 161 ±93 and TQP: 246 ±45 N). No statistical difference in the mean load was found among the 3 veneer materials for each preparation design except between IEC (306 ±101 N) and FP (161 ±93 N) veneers for TQP.
Preparation design did not influence the failure load of the veneer materials. Zirconia veneers were the least likely to fracture but the most likely to completely debond; feldspathic porcelain veneers exhibited the opposite characteristics.
长石质烤瓷贴面的破裂是一种重要的临床失败模式。因此，需要具有更高断裂负荷承受能力的陶瓷材料，特别是对于有副功能习惯的患者。
本研究的目的是研究材料（氧化锆、TZP、玻璃陶瓷、IEC 和长石质瓷，FP）设计（切缘重叠预备，IOP 和四分之三预备，TQP）和破裂模式与复合树脂基台支持的贴面的失效负荷之间的相关性。
使用 2 种设计（IOP、TQP）和相应的 2 个最终模具制备复合树脂基台（IOP 30 个，TQP 30 个）。每个系统（Y-TZP、IEC 和 FP）的每个设计制作 10 个贴面样本。将贴面粘接到模具上，进行包埋和压缩测试，直到在万能试验机上失效。通过双因素方差分析（α=.05）评估显著差异。
Y-TZP（IOP：244±81N 和 TQP：224±58N）、IEC（IOP：306±101N 和 TQP：263±77N）和 FP 贴面（IOP：161±93N 和 TQP：246±45N）的预备设计之间没有观察到统计学上的平均负荷差异。除了 TQP 中 IEC（306±101N）和 FP（161±93N）之间的差异外，每个预备设计的 3 种贴面材料之间的平均负荷没有统计学差异。
预备设计不影响贴面材料的失效负荷。氧化锆贴面最不容易破裂，但最容易完全脱粘；长石质瓷贴面则表现出相反的特征。
