Effect Of Recasting On Cytotoxicity And Mechanisms Of The Non-Nickel-Based Ceramic Alloys

Objective: To study the effects of recasting on ions release, cytotoxicity, cellcycle and apoptosis of the non nickel-based ceramic alloys.Methods:(1) the non-nickel-based ceramic alloys recast for1~3times wereavailable respectively after the non-nickel-based ceramic alloys provided bythe manufacturer having been cast1~3times. Before being recast again, thenon-nickel-based ceramic alloys should be treated with “the most appropriateway to treat metal alloys before recast”. According to ISO10993-5:2009standards, rectangular samples of the non-nickel-based ceramic alloys wereimmersed in DMEM culture medium,(2) Determined the concentration of ionsof the leaching liquor by ICP-MS total-quantization method,(3) L-929cellswere cultured with the leaching liquor of the non-nickel-based ceramic alloys.Relative growth rate (RGR) was analyzed using cell counting kit-8(CCK-8)assay and the shape of L-929cells was observed by an inverted phasecontrast microscope,(4) L-929cells were cultured with the leaching liquor, andthen staining by PI. Flow cytometry tested cell cycle progression,(5) L-929cells were cultured with the leaching liquor. Flow cytometry tested induced cellapoptosis. Annexin-V-FITC/PI apoptosis staining kit quantitative detected celldeath patterns.Results:(1) After casting1-3times, there presented no statistical increase inthe concentration of ions of Co-Cr ceramic alloys except Ga, the concentrationof Ga increased with the times of recast; after casting1-3times, therepresented no statistical increase in the concentration of ions of Ti ceramicalloys; after casting1-3times, the concentration of Ga increased with the timesof recast, and the concentration of Zn decreased. There presented nostatistical increase in the concentration of other ions of Pd-Cu ceramic alloys;after casting1time, Ag and Pd of Au-Pt ceramic alloys could not beendetected by ICP-AES, but they had been detected after casting2~3times. (2)Cytotoxical grades of Co-Cr ceramic alloys after casting1-3times weregrade1or2, the grades of Ti and Pd-Cu ceramic alloys after casting1-3timeswere grade1or2, and the grades of Au-Pt ceramic alloys after casting1-3times were grade0or1.(3) No statistically differences in cell cycle were foundfor the non nickel-based ceramic alloys between the samples cast for1timeand for2-3times, but Co-Cr ceramic alloys could restrain the synthesize ofDNA and the proliferation of L-929cells.(4) No statistically differences in therates of apoptosis and necrosis were found for the non nickel-based ceramicalloys between the samples cast for1time and for2-3times, but the rates ofapoptosis of Co-Cr and Ti ceramic alloys were above the negative control.Conclusion: It is preliminarily estimated that the biocompatibility of the nonnickel-based ceramic alloys, which were casted for1~3times, had notchanged.