@_mark_
Hi Mark,
the biggest issue is simply giving yourself enough time to build the right habits the first time around. The trumpet is first and foremost a "wind instrument", and that should be your focus.
Most trumpeters go through various stages of development. We start with "whatever we can get" and advance to a level that is hard to break though. Then we figure something out (or get help) and the next step comes along. At one point in time, we all have a bit of proficiency BUT want more range and end up using pressure to get it. This is legitimate, as pressure works - up to a point. The problem is, if we build a pressure habit, we will have to break it to get to the next step. Habits are tough to break as any drinker/smoker can tell us.
When we are at this stage, we need to ask the questions - how much is improvement worth and when does it make sense to make any changes. Very often a decision is made in mid playing season and the player only ends up screwing up his own reputation.
We make changes out of playing season! We can lay the plans and make preparations but never ever take a risk during times when we can play in public!
As far as teeth go, mine are crooked and I played to the side for 30 years. Then I mage some changes in my routine (more lipslurs and longtones), and the embouchure wandered more or less to the middle where I have been playing for the last 25 years.
I had an accident 18 months ago and now have a full denture instead the bottom teeth (no choice). Thanks to the Corona season, I had time to adjust and my playing is about where it was before the accident. My Circle of Breath, Earl Irons lip flexibilities, long tones and a lot of hymnbook were the way back.
As far as a teacher goes, I really do recommend getting some lessons early to at least get the daily routine, body use and ones own expectations pointed in the right direction. After that, success is very dependent on the players motivations. Even after 55 years of playing at all levels, I still take occasional lessons - some trumpet, some body use. There is still a whole lot to learn.
Best regards and good luck,
Rowuk