the asymptotic properties in dynamic panel data model is based only on cross-section dimension, N. the time dimension T is assumed to be fixed. but the asymptotic theory of panel cointegration model is based on both N and T. So the two models have differences in many ways. basically, if N>>T, it seems reasonable to use dynamic panel data. However, if N and T both large, you need to consider the stationarity of the time series, this is one of most important topics in high dimension data.