Depending on what files / documents you deleted you might be in a world of hurt. If they are audio files and you have a back up, you can restore them to the sessions audio files folder. If it's the session file that you deleted, and you have auto session back-up enabled, then you can launch your session from the most recent session back-up file (located in the session folder, session file back-ups folder). Launching the session this way will also tell you what if any audio files, fade files are missing. You might post additional ProTools related questions to the Digidesign support site, specifically the DUC. Lots of info there.
Tommy