My 76 year mother has a small piece of dental floss stuck in her back upper tooth. She can feel the end with her tongue on the inside of her gums, but can't seem to get it out with a toothpick. She reluctantly tried to floss it out with dental tape but can't get the new floss past the old floss. The dentist is closed until Tuesday. Any suggestions on a good way to dislodge it.