No Genotoxicity of a New Nickel-Free Stainless Steel

Abstract

Stainless steel is a metallic alloy largely employed in orthopedics, maxillofacial surgery and orthodontic therapy. However, the presence in its composition of a high quantity of nickel, an agent known to trigger toxic, allergic and cancerogenous responses in humans, is cause of some concern. In this study, we have investigated the in vitro mutagenicity and genotoxicity of a new nickel-free stainless steel, namely P558, in comparison to the conventional stainless steel AISI 316L. The cytogenetic effects were evaluated by studying the frequency of Sister Chromatid Exchanges (SCE) and chromosomal aberrations. Ames test was performed to detect the mutagenic activity. Both P558 and AISI 316L did not cause any significant increase in the average number of SCE and in chromosomal aberrations, either with or without metabolic activation. Furthermore, the Ames test showed that the extracts of both P558 and of AISI 316L are not mutagenic. Overall, these findings prove that P558 is devoid of genotoxicity and mutagenicity. The present results, together with other previous interesting observations that P558 promotes osseointegration, suggest that this new nickel-free stainless steel can represent a better alternative to other conventional steel alloys.

Preclinical Alterations of Oral Epithelial Cells in Contact With Orthodontic Appliances

“…The corrosion causes the release of metals from the alloys used for their manufacture. In this context, some studies have shown that contact of orthodontic appliances with the oral mucosa is unable to cause cytotoxicity or genotoxicity [28][29][30] . White patches and ulcerations reflect extensive tissue injury upon orthodontic treatment.…”

In vitro oxidative stress induced by conventional and self-ligating brackets

“…Knowledge of the genotoxic properties of orthodontic materials, such as oxidative stress, should be an important criterion for selecting an appliance that would have safe biological effects on patients. 28 The advantage of using an immortal cell line is that the cell can be grown indefinitely in culture. Performing analysis on primary cells from tissue donors (human gingival fibroblasts) does not offer such advantages and raises some ethical concerns.…”

Nickel-free austenitic stainless steels for medical applications

“…Montanaro et al from Italy have investigated in vitro the mutagenicity and genotoxicity of a new nickel-free stainless steel (Fe-17Cr-10Mn-3Mo-N), namely P558, in comparison to the AISI 316L [84,85]. The result of the cytogenetic effect and Ames test proved that P558 alloy is devoid of genotoxicity and mutagenicity, and suggested that this nickel-free stainless steel represents a better alternative to other conventional medical stainless steels.…”