A group of studies have focused on the cytotoxicity of materials and procedures in Orthodontics. Conventional cytotoxicity assessment (MTT, DNA synthesis) involving human gingival or PDL fibroblasts and oestrogenicity using an in vitro model, have been on eluents of alloys and adhesives.
The growing body of evidence suggests that additional methods beyond conventional assays should be adopted as screening tests. Such a tactic will allow the exploration of the effect of various substances deriving from polymeric degradation products or ions released from alloys on cells. Moreover, current trends emphasize the significance of the action of these substances at subtoxic concentrations.