I'm not sure if people have totally perfected the use of Cryogenics, for the human body to be frozen without "Damaging" it would have to freeze extremely quickly so that ice crystals don't form. The problem is that different parts of the body would freeze at different times (because of their makeup and density) which means it's very likely that a whole body would indeed be damaged.
There are how ever possible ways of dealing with this, but that's still in the testing stages.