Create a third database and import the tables from either
of the ones that you wish to compare, changing the table
names to identify which db they came from.
Then either import or link to the tables in the other db.
Now you can create queries for finding unmatched records
from each pair of tables in the db (queries / New / Find
unmatched). This will show you if any records were added
to the tables being compared.
If your concern is that one or more of the fields in one
or more of the tables have been changed, your query will
have to compare every field. Something like iif
(table1.field1 <> table1bkup.field1, "changed","same") in
the qbe pane should work.
Alternatively, you could just write over the newer db with
the data in the backup db. Then they will be the same.