Zirconia and radioactivity: An in vitro study to establish the presence of radionuclides in dental zirconia

Abstract

Statement of problem: Dental zirconia possesses concentrations of radionuclides, but their possible radioactivity is unknown.

Purpose: The purpose of this in vitro study was to evaluate the radioactivity and radionuclide concentration in dental zirconia.

Material and methods: Three specimens were obtained from commonly used dental yttria-stabilized tetragonal zirconia polycrystal materials: Vita In-Ceram YZ, Zirkonzahn, and Zirkonzahn Prettau-producing a powder for the evaluation of radioactivity through gamma spectrometry. For the determination of radioactivity, a group of radionuclides (Ac-228, Pb-212, Tl-208, Pb-214, Bi-214, and Be-7) was evaluated.

Results: The measurements of all the specimens reported that most activity came from the decay chain of uranium, radium, and thorium, obtaining a radioactivity of 11.082 Bq/kg for Vita In-Ceram YZ, <11.63 Bq/kg for Zirkonzahn, and <34.91 Bq/kg for Zirkonzahn Prettau.

Conclusions: Although all specimens contained radionuclides, their radioactivity was below the limit established by the International Atomic Energy Agency.