In vitro evaluation of the mutagenic and carcinogenic power of high purityzirconia ceramic

Tetragonal zirconia polycrystal (TZP) is a new interesting ceramic for the manufacture of medical devices. Its wide use in orthopedic and odontoiatric implants was limited till now by the high chemical and radiochemical impur ities of the raw materials. Purification processes now available allow to o btain high purity ceramic grade powders suitable for TZP ceramics manufactu re, even if their possible mutagenic and transforming effects are still unc lear. The aim of this work is to study in vitro the mutagenic and oncogenic effects of a new zirconia ceramic stabilized by yttria (Y-TZP). This ceram ic was sintered from high purity powders obtained by a process developed un der a project carried out within the Brite EuRam programme. For comparison, ceramics made from unpurified zirconia powder were also tested. Fibroblast s irradiated by a linear accelerator were used as positive control. The res ults obtained show that Y-TZP ceramic does not elicit either mutagenic or t ransforming effect on C3H/10-T-1/2 (10T(1/2)) cells and demonstrate that ce ramic from high purity powders can be considered suitable for biomedical ap plications from the point of view of the effects of its radioactive impurit y content. (C) 1999 Elsevier Science Ltd. All rights reserved.