Detrapping phenomena in stressed MOS devices are observed by monitoring electrical characteristics after a constant current stress is applied. The "see-saw" behavior of the density of interface states and the subsequent partial recovery of the threshold voltage give evidence that detrapping occurs in the capacitor and transistor. Threshold voltage reversal has two components, thermal recovery (TR) and field-assisted-recovery (FAR). These results suggest the occurrence of a degradation reversal which could be of importance in future device design.