[Dovecot] Auto rebuild indexes?

Here's an easy question for you. I'm restoring some emails from a backup. Do I need to delete or otherwise manually rebuild the indexes?

dovecot.index.cache dovecot.index.log dovecot-uidlist

Or will Dovecot itself detect that something is amiss and handle it on first folder access?

Using Maildir with Dovecot 1.2.9