Do Mormon dentists refer to non Mormon dental specialists?

Of course! Members of the Church of Jesus Christ of Latter-day Saints (commonly called "Mormons") do not have a problem promoting the businesses of those who are not members of the Church. If a Mormon dentist refers you to a specialist, it is his duty to refer you to someone he considers a good dental specialist, not a good Mormon. Religion and business are kept seperate, something most Mormons understand very well.