Department of Preclinical Research, Ivoclar Viadent, Benderersterasse 2, Schaan, Liechtenstein.
Int J Prosthodont. 2010 Nov-Dec;23(6):493-502.
The aim of this review was to systematically evaluate and compare the frequency of veneer chipping and core fracture of zirconia fixed dental prostheses (FDPs) and porcelain-fused-to-metal (PFM) FDPs and determine possible influencing factors.
The SCOPUS database and International Association of Dental Research abstracts were searched for clinical studies involving zirconia and PFM FDPs. Furthermore, studies that were integrated into systematic reviews on PFM FDPs were also evaluated. The principle investigators of any clinical studies on zirconia FDPs were contacted to provide additional information. Based on the available information for each FDP, a data file was constructed. Veneer chipping was divided into three grades (grade 1 = polishing, grade 2 = repair, grade 3 = replacement). To assess the frequency of veneer chipping and possible influencing factors, a piecewise exponential model was used to adjust for a study effect.
None of the studies on PFM FDPs (reviews and additional searching) sufficiently satisfied the criteria of this review to be included. Thirteen clinical studies on zirconia FDPs and two studies that investigated both zirconia and PFM FDPs were identified. These studies involved 664 zirconia and 134 PFM FDPs at baseline. Follow-up data were available for 595 zirconia and 127 PFM FDPs. The mean observation period was approximately 3 years for both groups. The frequency of core fracture was less than 1% in the zirconia group and 0% in the PFM group. When all studies were included, 142 veneer chippings were recorded for zirconia FDPs (24%) and 43 for PFM FDPs (34%). However, the studies differed extensively with regard to veneer chipping of zirconia: 85% of all chippings occurred in 4 studies, and 43% of all chippings included zirconia FDPs. If only studies that evaluated both types of core materials were included, the frequency of chipping was 54% for the zirconia-supported FDPs and 34% for PFM FDPs. When adjusting the survival rate for the study effect, the difference between zirconia and PFM FDPs was statistically significant for all grades of chippings (P = .001), as well as for chipping grade 3 (P = .02). If all grades of veneer chippings were taken into account, the survival of PFM FDPs was 97%, while the survival rate of the zirconia FDPs was 90% after 3 years for a typical study. For both PFM and zirconia FDPs, the frequency of grades 1 and 2 veneer chippings was considerably higher than grade 3. Veneer chipping was significantly less frequent in pressed materials than in hand-layered materials, both for zirconia and PFM FDPs (P = .04).
Since the frequency of veneer chipping was significantly higher in the zirconia FDPs than PFM FDPs, and as refined processing procedures have started to yield better results in the laboratory, new clinical studies with these new procedures must confirm whether the frequency of veneer chipping can be reduced to the level of PFM.
本综述的目的是系统评估和比较氧化锆固定义齿（FDP）和烤瓷熔附金属（PFM）FDP 的贴面崩瓷和内冠破裂的频率，并确定可能的影响因素。
在 SCOPUS 数据库和国际牙科研究协会摘要中检索了涉及氧化锆和 PFM FDP 的临床研究。此外，还评估了纳入 PFM FDP 系统评价的研究。联系了任何氧化锆 FDP 临床研究的主要研究者，以获取更多信息。根据每个 FDP 的可用信息，构建了一个数据文件。贴面崩瓷分为三个等级（等级 1=抛光，等级 2=修复，等级 3=更换）。为了评估贴面崩瓷的频率和可能的影响因素，使用分段指数模型来调整研究效果。
没有一项关于 PFM FDP 的研究（综述和额外的搜索）充分满足本综述的标准，无法纳入。确定了 13 项关于氧化锆 FDP 的临床研究和两项同时调查氧化锆和 PFM FDP 的研究。这些研究涉及 664 个氧化锆和 134 个 PFM FDP 的基线。595 个氧化锆和 127 个 PFM FDP 有随访数据。两组的平均观察期约为 3 年。氧化锆组的内冠破裂发生率低于 1%，而 PFM 组为 0%。当所有研究都包括在内时，记录了 142 个氧化锆 FDP 的贴面崩瓷（24%）和 43 个 PFM FDP 的贴面崩瓷（34%）。然而，研究在氧化锆的贴面崩瓷方面差异很大：4 项研究中发生了 85%的所有崩瓷，43%的崩瓷包括氧化锆 FDP。如果仅包括评估两种核心材料的研究，则氧化锆支持的 FDP 的崩瓷率为 54%，PFM FDP 的崩瓷率为 34%。当调整研究效果的生存率时，氧化锆和 PFM FDP 之间的崩瓷差异具有统计学意义（P=0.001），3 级崩瓷也具有统计学意义（P=0.02）。如果考虑所有等级的贴面崩瓷，典型研究 3 年后 PFM FDP 的生存率为 97%，而氧化锆 FDP 的生存率为 90%。对于 PFM 和氧化锆 FDP，1 级和 2 级贴面崩瓷的频率明显高于 3 级。对于氧化锆和 PFM FDP，贴面崩瓷的频率在压制材料中明显低于手糊材料（P=0.04）。
由于氧化锆 FDP 的贴面崩瓷频率明显高于 PFM FDP，并且由于精细的加工工艺在实验室中已经开始产生更好的结果，因此必须进行新的临床研究，采用这些新的工艺，以确认贴面崩瓷的频率是否可以降低到 PFM 的水平。
