These photos are real and not manipulated. They show something natural and normal – the exfoliation of teeth. This is something we all understand; children loose their teeth and the new tooth pushes up from beneath.
However, what we don’t think about very much is the process of storing the new tooth underneath the old tooth. For lower teeth his happens in the jaw. For upper teeth this happens just below the nose.
Both of these pictures are simply the skulls of children who have died before getting rid of their milk teeth. As a word of warning – they’re freaky.
There’s no doubt in my mind that describing an encounter where adventuring characters come across bones that look as odd as this would mislead and alarm the party. They may assume they’re dealing with monsters. If you insist, perhaps after medical skill rolls (without any amazing successes) that the bones are natural, normal and human then the characters may wonder about mutants and vampires.
It may be tempting to show them the pictures too (I think the black and white one is especially scary) but I think that may reveal your hand. Perhaps do so afterwards or modify the edges of the pictures so they look less photographic and more photoshopped or created.
What do you think? Freaky? Is this something only an evil GM would do?
Front view photo via io9.com, black and white photo shared without attribution on Twitter.