When I was in college, my professors always addressed me as "Mr. Huston." The practice of addressing a student with a title is something that I begin the first day of class & I believe that it's very important not to address a student by first name in class.
Using a title such as Mr, Mrs, Ms, or Miss helps from the beginning to establish appropriate boundaries between teacher & student. It's important because I think that students need to be reminded that:
(1) I'm here as your instructor & that's my role in this class: I'm not here to be your buddy;
(2) you're an adult now, not a child, so I'm addressing you as such & I expect you to behave accordingly;
(3) this is a career college & I'm here to model professional behavior, & the professional addresses clients, customers, superiors &, sometimes, even colleagues by title & surname unless & until they invite you to operate on a first-name basis;
(4) these are the ground rules for this classroom & you must conform here much as you will be expected to conform to corporate cultures wherever you go in your career.
More than anything else that I do, this incurs rebellion from my students. I have some who still insist on calling me by first name & fight tooth & nail to get me to do the same, But I won't cross that boundary in front of another student. I may address some students by first name privately when I'm certain that they can distinguish between the roles of teacher & friend.