Department of Prosthodontics, School of Dentistry, Albert-Ludwigs University, Freiburg, Germany.
J Oral Rehabil. 2013 Jan;40(1):51-9. doi: 10.1111/j.1365-2842.2012.02323.x. Epub 2012 Jun 4.
To compare the fracture resistance of zirconia 3-unit posterior fixed dental prostheses (FDPs) frameworks veneered with different veneering materials and techniques before and after artificial ageing. Forty-eight zirconia 3-unit FDPs, representing a missing first molar, were adhesively cemented on human teeth. The zirconia frameworks were randomly distributed according to the veneering materials and techniques into three groups, each containing 16 samples: group LV (layering technique/Vintage ZR), group LZ (layering technique/ZIROX) and group PP (CAD/CAM and press-over techniques/PressXZr). Half of each group was artificially aged through dynamic loading and thermocycling to simulate 5 years of clinical service. Afterwards, all specimens were tested for fracture resistance using compressive load. An analysis of variance (anova) was used to assess the effect of veneering ceramic and artificial ageing on fracture resistance (P < 0·05). Except for one minor cohesive chipping in group LV1, all specimens survived artificial ageing. The mean fracture resistance values (in Newton) of different non-aged (± s.d.)/aged (± s.d.) groups were as follows: LV0 2034 (± 401)/LV1 1625 (± 291); LZ0 2373 (± 718)/LZ1 1769 (± 136); and PP0 1959 (± 453)/PP1 1897 (± 329). Artificial ageing significantly reduced the fracture resistance in groups veneered with the layering technique (P < 0·05), whereas no significant effect was found in specimens veneered with the CAD/CAM and press-over techniques. All tested systems have the potential to withstand occlusal forces applied in the posterior region. The combination of the CAD/CAM and press-over techniques for the veneering process improved the overall stability after artificial ageing, relative to the layering technique.
比较不同饰瓷材料和技术的氧化锆三单位后牙固定修复体（FDP）在人工老化前后的抗折强度。将 48 个氧化锆三单位 FDP 代表缺失的第一磨牙，用黏结剂黏固在人牙上。根据饰瓷材料和技术，将氧化锆支架随机分为三组，每组 16 个样本：LV 组（分层技术/ Vintage ZR）、LZ 组（分层技术/ZIROX）和 PP 组（CAD/CAM 和压盖技术/PressXZr）。每组的一半样本通过动态加载和热循环进行人工老化，以模拟 5 年的临床服务。然后，所有样本均通过压缩载荷测试抗折强度。采用方差分析（anova）评估饰瓷陶瓷和人工老化对抗折强度的影响（P<0.05）。除 LV 组 1 中有一个小的黏结性剥落外，所有样本均经受住了人工老化。不同未老化（±s.d.）/老化（±s.d.）组的平均抗折强度值（以牛顿为单位）如下：LV0 2034（±401）/LV1 1625（±291）；LZ0 2373（±718）/LZ1 1769（±136）；PP0 1959（±453）/PP1 1897（±329）。人工老化显著降低了采用分层技术饰瓷的组的抗折强度（P<0.05），而采用 CAD/CAM 和压盖技术饰瓷的样本则无显著影响。所有测试系统都有可能承受后牙区的咬合力。与分层技术相比，CAD/CAM 和压盖技术联合用于饰瓷过程提高了人工老化后的整体稳定性。
