Ok, you can only explunge a record that is convicted, so since there is no conviction, there is nothing you can explunge.
I will still argue despite what is said, that national fingerpints are not destroyed. They are keep at least in National Security.
Also remember fingerprints don't say you ever did a crime, that record is the criminal records, Fingerprints are on file only to prove Identity. 100s of thousands of people get fingerprinted each year for all sorts of other reasons.