I agree with Wendell on the side screen. Best thing that ever happened to the board.
No one would EVER remove your posts from the board.
The best way to deal with this is to find your name on a post at the top left. Left click on it, then select View Posts. This will show you all of your posts from ascending to descending. Find the post in question and click on it. It should bring you to your post. If it has been deleted, you will know.
If you think it has been deleted, I would PM me. I can check the logs and see who, what, and when has happened.