If you have the recycle bin in AD enabled you can restore deleted items.
To get all the items in recycle bin:
Get-ADObject -ldapFilter:"(msDS-LastKnownRDN=*)" -IncludeDeletedObjects
To get one item (change the username):
Get-ADObject -Filter {displayName -eq "username"} -IncludeDeletedObject
To restore one item (change the username):
Get-ADObject -Filter {displayName -eq "username"} -IncludeDeletedObjects | Restore-ADObject