Creep in amalgam class V restorations

The purpose of the investigation was to examine the creep rate in an amalgam Class V restoration. The stresses in a central bucco-lingual plane of a loaded bicuspid with a Class V restoration were computed with aid of the finite element method. When the stresses were known, the creep rate was calculated. The results showed that the creep rate of a load of 150 N varied between 0.6% and 3.5% per 104 s for amalgams with large differences between their viscoelastic behaviors. A gap between the restoration and the cavity margin will thus occur if a tooth is often heavily loaded.