Duplicate emails in Exchange

We recently were forced to perform a restore of our priv.edb database and then a restore of individual mailboxes. Since the database was old, we didn’t ‘overwrite’ when we did the restore. As a result of this, we have several hundred mailboxes with lots of duplicate email addresses and contacts. Is there an easy way to remove duplicate emails and contacts with the least impact to the individual users? Thanks for your help!