Smooth or merge the hand and the forearm I have made a model in Sculptris which is a 3d sculpting program from the Zbrush team. And I have separated my whole character body from hand, feet and eyes. I exported it to .obj and what I'm trying to do is to "merge" all the separated parts I have sculpted. 

But my problem is that it was exported as a single object so there's a clear separation between forearm and hands, feets and legs. And i don't know how I have to proceed in Blender to "merge" them together. Here's an image to illustrate my problem.



I have never used blender. (it's my first time with sculptris too :p). So please be as precise as you can if you know how i can fix this. Thank you.
Since user hawkenfox suggested it, I will post my comment as an answer:

You need to Tab into Edit Mode, RClick to select a vertex on the hand, press Ctrl L to select all the connected (Linked) geometry, then H to Hide the hand geometry. This will let you see what's going on with the arm underneath and you can select then delete the faces of the arm stump. Then Alt H to un-Hide. Repeat this for the arm and delete the faces on the wrist of the hand geometry. Then you can use Merge (Alt M) or Fill (F) to connect the hand to the forearm. Whether modeling in Blender or Sculptris, it's better if you can sculpt all as one piece in the future and avoid this extra work.