Merge two databases: OLD SITE -> NEW SITE

I am working to a restyle of a website.

I made DB dump from remote server and made local installation, then started to work on my local machine.

While i’ve been working other post have been added to remote site, so database has new entry that i missed.

Now i need to put online my restyled site and integrate the new entries in my DB. How can i do this?
Using Export/import tool would overwrite my new DB?

NOTE: The structure of new db is completely alterated from the old one: got new Post-type, categories, custom fields, ecc…