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No, not while they are in default.
I think you would be better off to rehab the loans - have the lates removed after rehab and then pay in full if you want. I'm not 100% sure, but I think you can only remove the lates after the rehab is completed and only if they are federal loans. Check in the student loan section here to verify.
But if you are currently in default and you pay it off, then it will still show as a default, but a paid one.
Much better to get rid of the default notation