Editing Postbit will make Thread to a "new" one

[bpr]

Hi guys,
I would like. that a thread starter who did not get any answers within 24hrs that he can edit his post or click on a button to make the post come back in the top10 threads to get more attention.

However I am asking on which field the top10 is working on if you create it via the standart widget for your forum sidebar.

does anybody know that which table and which column is important for that ? couldnt really find anything else than

thread.lastpost which has a timestamp.

And another question is, which hook to I have to use for update the timestamp or whatsoever before sending the editied post.

All the best,
bpr