Molecular dynamics simulations were employed in order to examine the effects of the dendritic topology to the characteristics of local environment and its association with the manifestation of glass transition phenomena. Dendrimer models of the AB(2) type of generations 3, 4, and 5 were simulated in the melt state in a wide temperature range. Investigation of intradendrimer motional properties revealed that connectivity constraints inherent to this topology impose a strong dynamic contrast within the dendritic structure which increases with molecular size. This strong separation of the relevant time scales particularly at the largest size model, combined with structural rearrangements both of intra- and intermolecular nature, offers a new basis for the rationalization of recent experimental findings where existence of multiple dendrimer glass transitions was observed.