My daughter bumped her chin 3 weeks ago and only 3 days ago a massive black bruise has come up. She has been to the dentist as her gums were a little bruised as well to get her teeth checked and they are fine. The bruise has faded a little and some areas have gone yellow which is good but now the bruise is working its way up her chin in a straight line. The dentist thinks she could have a fractured chin, could this be right? She is in no pain unless you press on it but it did hurt her when she was swimming. If it is a fracture, does it heel by itself?