Professional arrogance in health care fields?

I've noticed a pattern than seems to be forming around professionals in health care fields, particularly medicine and dentistry. I'm not formally educated in either field, but I'm an intelligent middle-aged man, and my curiousity tends to result in me acquiring various tidbits of knowledge that laypeople would not ordinarily have. For example, I was at the dentist recently to have an old filling replaced after it had fallen out. When the dentist asked me where it had come out, I replied that it was on my "Four-six M", which is dental lingo for the forward facing surface of the 1st molar in the lower-right quadrant of my mouth. The dentist was impressed that I correctly identified the filling's location with the proper terminology, and continued on his way. Here's what I've found. If I'm talking to an older professional (roughly 45 or older), they tend to respond to such knowledge as if it were 'classified', and I shouldn't be worrying my little head with it - in a somewhat patronizing fashion. Younger doctors, on the other hand, tend to almost universally react by not even acknowledging that I knew something they wouldn't expect from a non-doctor. Furthermore, they seem to immediately switch gears and start discussing the upcoming procedure with a more complicated vocabulary, assuming that you already know nearly as much as they do. Basically, the reactions seem to be like this: Old doctor: "My knowledge is special, and you shouldn't be able to have it, so I'm going to patronize you like a child" Young doctor: "It was unlikely you would know that, but it's cool that you do, and I'm happy to discuss things in those terms if you wish." Any ideas why this shift in mentality might be occurring?
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Four-six M....are you kidding? That is not dental lingo. I'm surprised the dentist did not have to pick himself off the floor from laughing. You, my friend are a hoot. Have a great day.
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