Development of a New Zirconia-Toughened Alumina: Promising Mechanical Properties and Absence of In Vitro Carcinogenicity

Abstract

High purity alumina as well as zirconia ceramics have been widely used as orthopaedic implant biomaterials and dental devices displaying optimal, but sometimes exclusive, mechanical properties. In order to combine the advantages of alumina and zirconia ceramic materials different types of composites have been developed in which either zirconia is dispersed in an alumina matrix or vice versa. Orthopaedic and dental implant biomaterials are expected to be in contact with living tissues for a long period of time and their long term toxicity must be carefully evaluated. In this study we report the development of a high performance chromia-doped Zirconia Toughened Alumina (ZTA) material which displays promising mechanical properties in terms of hardness, strength and fracture toughness that make it suitable for prosthesis even for small joints. The long-term biocompatibility of this material was also evaluated, mainly in terms of DNA damage, mutagenicity and cancerogenetic potential in mammalian cells. The results obtained suggest that this new ZTA material does not display any long-term carcinogenic effect and it is suitable for biomedical applications from a cancerogenetic point of view. In conclusion, we report the development of a new chromia-doped ZTA material with interesting properties both from a mechanical and a biocompatibility point of view which warrant further studies on its suitability as a candidate biomaterial for orthopaedic implants and dental devices.

In Vivo Characterization of Zirconia Toughened Alumina Material: A Comparative Animal Study

“…In a previous study we reported a new ZTA ceramic obtained within a project aimed to develop new ceramic materials of high strength and toughness suitable for biomedical applications and demonstrated that it did not elicit mutagenic nor carcinogenic effects in vitro (7). The material is currently under consideration for patent and we proposed it as a suitable biomaterial for load bearing applications such as orthopaedic implants or dental devices.…”

Strength and reliability of alumina ceramic femoral heads: Review of design, testing, and retrieval analysis

“…Additives such as zirconia are incorporated into alumina matrices to serve as toughening agents. The details of these mechanisms are beyond the scope of this review, but in short, controlled phase transformation of sub-micron zirconia particles within the alumina matrix prevents subcritical crack propagation, resulting in decreased fracture rates (De Aza et al, 2002;Insley et al, 2002;Maccauro et al, 2009). However, these materials have a relatively short clinical history, so further monitoring is necessary.…”

Effect of the Compositions on the Biocompatibility of New Alumina–Zirconia–Titania Dental Ceramic Composites

“…These biocompatibility capabilities are preserved also on binary zirconia-alumina composites, as assessed by Maccauro et al [49]. Their results, based on DNA damage, mutagenicity, and cancerogenetic potential in mammalian cells, confirmed that ZTA material could be considered suitable for biomedical applications.…”