Dr Byron Glenn does not consent

[Forsyth]

In the UK, Dentists are not called Doctors.

Nor are surgeons - they invariably start off as being a doctor, but when they qualify as a surgeon they become Mr, Mrs, Miss, Ms again. Apparently this is in recognition of the days when a "doctor" was a physician who regarded surgery as something akin to butchery. Nowadays surgeons see not being a doctor as a mark of superiority over the physicians and can be touchy about being called "doctor"!