This is something I realized when I got lip fillers recently. None of my family members knew, lol. It was really barely noticeable... You could only see a slight needle mark, but after about 3-4 days, it completely disappeared. But this wasn't the first time, but the second time. I had both done by the same doctor, and the one thing they had in common was that there was no bruising... I thought that getting lip fillers usually leaves some blue bruising around the mouth, but there wasn't a single one here. I think it's because they looked at me very carefully during the procedure. I don't know about anything else, but the fact that there was no bruising is really amazing and I keep thinking about it, lol.