In Britain, when a doctor becomes a surgeon, they become a fellow of the Royal Academy of Surgeons (and use the initials FRCS after their names), and they revert to the title "Mister"
A letter would be addressed to Mr. and Doctor. If they are both Doctors it would be Doctor and Doctor.
'Mr' is the usual designation for a consultant or senior surgeon.
A person with a PhD is addressed as Dr.
Mr and Mrs = Familie
Hazel addressed Mr. Baxter as 'Mr. B'
He's still addressed as Mr. President.
Some therapists hold the degrees Ph.D.,Ed.D., or PsyD. these degree holders are addressed as Dr...Others have Masters degrees and are generally addressed as Mr. or Ms.
In Japan, both doctors and teachers are addressed as "sensei", a term of respect.
Is it Dear Mr. President when writing a letter?
It should be addressed as Rev and Mrs John Doe.
Mr.
as "Mr. President" or "Sir"