title: Differences of cytotoxicity of orthodontic bands assessed by survival tests in Saccharomyces cerevisiae.
abstract: The aim of this study was to evaluate the cytotoxicity induced by orthodontic bands through survival tests on Saccharomyces cerevisiae, a microorganism that presents several genetic and biochemical characteristics similar to human cells. Three groups of bands were evaluated: silver soldered (SSB), laser soldered (LSB), and bands without any solder (WSB). Yeast cells were directly exposed to the bands and indirectly, when a previous elution of the metals in artificial saliva was performed. The negative control was composed of yeast cells or artificial saliva not exposed to any kind of metal. In the direct exposure experiments, all tested groups of bands induced a slight reduction in yeast viability compared to the control. This effect was more intense for the SSB, although not statistically significant. For the indirect exposure experiments, the SSB induced a statistically significant decrease in cell viability compared to the LSB. There were no significant differences between the survival rates of the negative control and the LSB group in both direct and saliva tests. SSBs were cytotoxic, whilst LSBs were not, confirming that laser soldering may be a more biocompatible alternative for use in connecting wires to orthodontic appliances.
authors: Department of Orthodontics, Dentistry Faculty, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga 6681, Building 6, Room 209, 90619-900 Porto Alegre, RS, Brazil.
authors: Tatiana Siqueira
authors: TS
authors: Gonçalves
authors: Department of Orthodontics, Dentistry Faculty, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga 6681, Building 6, Room 209, 90619-900 Porto Alegre, RS, Brazil.
authors: Luciane Macedo
authors: LM
authors: de Menezes
authors: Immunology and Microbiology Laboratory, Biosciences Faculty, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga 6681, Building 12, Lab 12D, 90619-900 Porto Alegre, RS, Brazil.
authors: Luciele Gonzaga
authors: LG
authors: Ribeiro
authors: Immunology and Microbiology Laboratory, Biosciences Faculty, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga 6681, Building 12, Lab 12D, 90619-900 Porto Alegre, RS, Brazil.
authors: Catieli Gobetti
authors: CG
authors: Lindholz
authors: Immunology and Microbiology Laboratory, Biosciences Faculty, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga 6681, Building 12, Lab 12D, 90619-900 Porto Alegre, RS, Brazil.
authors: Renata
authors: R
authors: Medina-Silva
mesh_terms: D006801:Humans; D008422:Materials Testing; D009967:Orthodontic Appliances / Q000382:microbiology*; D012441:Saccharomyces cerevisiae / Q000187:drug effects*