easy.
the premise is certain message was wiped out on your iphone harddrive, but it has NOT been PHYSICALLY OVERWRITTEN YET.
first off, you need to make sure your iphone can run a win32 program, i hope apple OS can do that.
then you can install any disk recovery softwares such as diskrecovery etc to bring back the data lost.
Again this would only work with the situation that your data has been wiped out, (not in the recycle bin), but on physical harddrive, those information were still there, and only been marked as "delete", as a software design inefficiency, so then you can use disk recovery softwares to recover it back.
if you wiped out the data, and refilled your harddrive with new data, then most likely your already done, and nothing else can be done to rescue anything.