Any doctor who properly manages his practice can hit $400K. Of course, if you only want to work four days a week, have limited hours, and not invest in your practice you may make less but $400K is very attainable for US physicians.
If they own their practice, sure.
Really depends on what you do and how you are staffed.
One of my best friends is a Dentist and Orthodontist.
Owns two practices with his wife and makes well over a million a year.
She does all the administrative work and staffing, he does ALL the professional work.
They have 8 employees.
He staffs low and works 5 - 10-hour days, Tues-Sat. Pays his people well but works a crazy pace.
He draws in tons of people because he's open late and on Saturdays.
The money is in braces for young adults. It's the new thing now. He can sell braces to anyone because people are obsessed with their looks more than ever.