"Sorry to bother you" in an email? I recently sent an email to a professor asking him about an administrative problem I was having, but after I'd hit the send button, I realized I'd forgot to say: "Sorry to bother you" or something of that sort in the beginning... 
Now I'm wondering is that considered impolite? Shoud you apologize to professors for bothering them or does that just make you sound phony?  I greeted him with"Dear Professor X", told him who I was, asked the question, and thanked him in advance. 
He answered my question and all, but I'm just asking for future reference.
I think that @ndpl hit the nail on the head when he commented that what's most important is that your message to the professor be clear and concise. 

During an academic semester I, like most academics, get a crazy number of emails. (I'm an assistant professor of mathematics at a college in the US.) If your email is short and to the point then chances are I'll be able to read it right away, decide what action on my part needs to be taken (if any), and move on to the next email. Empty statements like "I'm sorry to bother you." are polite, but just make my goal of getting through all the unread messages in my inbox that much harder to achieve. 

So if your email was written in a professional manner, but was just terse, that's absolutely fine.