Department of Oral Rehabilitation, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
J Oral Rehabil. 2010 Aug;37(8):641-52. doi: 10.1111/j.1365-2842.2010.02094.x. Epub 2010 Apr 9.
Zirconia is unique in its polymorphic crystalline makeup, reported to be sensitive to manufacturing and handling processes, and there is debate about which processing method is least harmful to the final product. Currently, zirconia restorations are manufactured by either soft or hard-milling processes, with the manufacturer of each claiming advantages over the other. Chipping of the veneering porcelain is reported as a common problem and has been labelled as its main clinical setback. The objective of this systematic review is to report on the clinical success of zirconia-based restorations fabricated by both milling processes, in regard to framework fractures and veneering porcelain chipping. A comprehensive review of the literature was completed for in vivo trials on zirconia restorations in MEDLINE and PubMed between 1950 and 2009. A manual hand search of relevant dental journals was also completed. Seventeen clinical trials involving zirconia-based restorations were found, 13 were conducted on fixed partial dentures, two on single crowns and two on zirconia implant abutments, of which 11 were based on soft-milled zirconia and six on hard-milled zirconia. Chipping of the veneering porcelain was a common occurrence, and framework fracture was only observed in soft-milled zirconia. Based on the limited number of short-term in vivo studies, zirconia appears to be suitable for the fabrication of single crowns, and fixed partial dentures and implant abutments providing strict protocols during the manufacturing and delivery process are adhered to. Further long-term prospective studies are necessary to establish the best manufacturing process for zirconia-based restorations.
氧化锆在其多晶态晶体结构上具有独特性，据报道其对制造和处理过程敏感，并且对于哪种加工方法对最终产品的危害最小存在争议。目前，氧化锆修复体通过软质或硬质铣削工艺制造，每个制造商都声称自己的工艺优于其他工艺。报道称，饰面瓷的剥落是一个常见问题，并被认为是其主要的临床缺陷。本系统评价的目的是报告通过两种铣削工艺制造的氧化锆基修复体的临床成功率，具体涉及修复体的基底断裂和饰面瓷剥落问题。在 1950 年至 2009 年间，我们在 MEDLINE 和 PubMed 中对氧化锆修复体的体内试验进行了全面的文献回顾，并对手头相关牙科杂志进行了手动搜索。共发现 17 项涉及氧化锆基修复体的临床试验，其中 13 项是关于固定局部义齿的，2 项是关于单冠的，2 项是关于氧化锆种植体基台的，其中 11 项基于软质铣削氧化锆，6 项基于硬质铣削氧化锆。饰面瓷的剥落是一个常见问题，基底断裂仅在软质铣削氧化锆中观察到。基于数量有限的短期体内研究，氧化锆似乎适合用于制造单冠以及固定局部义齿和种植体基台，但需要严格遵守制造和交付过程中的规范。进一步的长期前瞻性研究对于确定氧化锆基修复体的最佳制造工艺是必要的。
