Cytotoxicity of dental casting alloys after conditioning in distilled water.
OBJECTIVE
This study investigated the cytotoxicity of various types of dental casting alloys after they had been conditioned in distilled water.


METHODS
The casting alloys investigated included one high-noble alloy (Bioherador N) and six base-metal alloys, including four Ni-Cr alloys (Remanium CS, Heranium NA, Wiron 99, CB Soft), one Co-Cr alloy (Wirobond C), and one Cu-based alloy (Thermobond). Ten disks from each alloy were conditioned in distilled water at 37 degrees C for either 72 or 168 hours. The cytotoxicity of the alloys was then tested on Balb/C 3T3 fibroblasts, which were exposed to the alloys for 3 days at 37 degrees C. Cell viability was determined by the MTT method. The data were analyzed by ANOVA, and follow-up comparison between the groups was carried out using Tukey and t tests.


RESULTS
ANOVA revealed a significant effect of alloy type and conditioning time (P < .001). Bioherador N was significantly less toxic than all the other alloys in the 72-hour conditioned group. After 168 hours of conditioning, its cytotoxicity was not different (P > .05) from that of Remanium CS, Wiron 99, and Wirobond C. Thermobond and CB Soft were significantly more toxic than the other alloys at both conditioning times.


CONCLUSIONS
Conditioning of base-metal alloys, other than those containing Cu, for 168 hours in distilled water makes their cytotoxicity levels comparable to that of the high-noble alloy.
Al-Hiyasat
Ahmad S
AS
Department of Restorative Dentistry, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan. hiyasat@just.edu.jo
Darmani
Homa
H
Bashabsheh
Omar M
OM
D000535:Aluminum / Q000633:toxicity; D000704:Analysis of Variance; D000818:Animals; D041702:BALB 3T3 Cells / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002858:Chromium Alloys / Q000633:toxicity; D004396:Coloring Agents; D003300:Copper / Q000633:toxicity; D003722:Dental Alloys / Q000633:toxicity*; D003734:Dental Casting Investment / Q000633:toxicity*; D006047:Gold Alloys / Q000633:toxicity; D016555:Matched-Pair Analysis; D008422:Materials Testing; D051379:Mice; D009532:Nickel / Q000633:toxicity; D010984:Platinum / Q000633:toxicity; D013696:Temperature; D013778:Tetrazolium Salts; D013844:Thiazoles; D013997:Time Factors; D014867:Water / Q000737:chemistry
D002858:Chromium Alloys; D004396:Coloring Agents; D003722:Dental Alloys; D003734:Dental Casting Investment; D006047:Gold Alloys; D013778:Tetrazolium Salts; D013844:Thiazoles; D014867:Water; D010984:Platinum; D003300:Copper; D009532:Nickel; D000535:Aluminum; C022616:thiazolyl blue