Something to bear in mind about Doctor Doom: AFAIK, the canon explanation for Doom's deformity is that he was slightly scarred from the explosion that got him kicked out of his university, but the vast majority of his scarring comes from him strapping a red-hot iron mask to face. However, Doom has repeatedly switched bodies since then - I'm pretty sure his current one is a clone. In order for him to still have the same level of scarring, he has to have burned his own face again, even though he could have just kept his unaltered face.