Creep, Hardness, and Elastic Modulus of Lingual Fixed Retainers Adhesives.

The aims of this study were twofold: a) to characterize a wide array of time-independent and -dependent properties and b) to find possible correlations among the properties tested. Seven commercially available orthodontic adhesives were included in this study and ten cylindrical specimens were prepared from each material. Five specimens from each material were used for the characterization of Martens Hardness (HM), indentation modulus (E), and elastic index (η), and the remaining five for the determination of indentation creep (C).