Three professors (apart from Dumbledore) come to mind:
First, Minerva Mcgonagall. In the Order of the Phoenix, we see Minerva go head to head with Umbridge about Harry’s future. She’s dedicated to Harry’s well being, but also to standing up for students in the face of admin/legality trying to pass along further harm. In the 7th book, she is dedicated to Harry’s success against Voldemort, arguably for the greater good but also out of pure love and admiration for Harry. In the 3rd book, she’s dedicated to Hermione achieving all her goals by providing her a time turner. The moral: Minerva is my queen. She’s the teacher I aspire to be.
Second, Severus Snape. Odd choice, and not only because I’m a Slytherin. I see Snape’s dedication in both a positive and negative light. He only accepts students with the highest potions scores for his advanced classes, making it clear he’s purely dedicated to the success of his brightest which arguably isn’t so good. He’s positive in that he is dedicated to Harry’s occlemency (spelling idk) lessons, although they don’t go so well. He’s dedicated to Dumbledore, which in turn in my eyes makes him dedicated to students because at the end of the day, if he didn’t believe in students or education he would have found another job.
Third, and twisted, is Dolores Umbridge. She is the example of the kind of dedicated teacher no one wants or needs. She believes she’s doing what is best for Hogwarts. She does not take into account the school culture, the culture of the students, or their best interests to her but rather pursues wholeheartedly what she deems is the “right” form of education. She’s dedicated to proving all those she disagrees with wrong that she ends up doing more harm than good. She’s the example of a teacher so dedicated to her students that she fails to see the harm she’s doing. We have to be aware of those who are seemingly dedicated to students but actually dedicated to their own self interest, then use students as a decoy.