The intern primitive is a hoax.
While one can accept that there might be attorneys, three or four of them, among the primitives, one doubts Skins's island holds much of an attraction for other professionals, who simply don't have the time to hang around there.
Physicians and dentists and veterinarians and somesuch are just too busy in real life to bother with Skins's island.
I suspect the intern primitive, rather than being a dentist, is the person who comes into the office after office-hours, to clean it.