Kavan, very good points. This my natural head position (not parallel to Frankfort), which accentuates my sloping forehead, but reduce the lower third recession. If I want to SNA to be in a more normal range, I will have to change (tilt down) my natural head position and make a CCW?
Thanks
There are some adjustments they need to make for what I call 'cranial tipping'. It's not a matter of tilting your head down more. It's a matter of the cranium being oriented on an incline at an angle kind of far from the horizont. Those types of orientations CHANGE how one's face projects relative to some vertical drop lines.
I'm finding that people with 'wierd' ANB angles and forward faces to those red drop lines but when you look at them also look like they have some recession that the lines don't reveal, seem to have the tipped cranium in common. 'Weird' ANB in the sense one looks for something more than '4' for the class 2 skeletal.
Anyway, the cranial orientation, (well according to my observations) is somewhat parallel to the S-N line. Not exactly, but somewhat. Orientation in terms of drawing a line from one part of the forehead to the back of the skull such that THAT line is the LONGEST. The length of the skull is basically, the longest line you can get to where my line starts to somewhere in back where it ends.
S-N lines that are inclined a LOT away from the horizont often reveal the tipped cranial orientation. Also, not everyone actually has a horizontal Franfort line.
Here are some full cephs.
Person 'A' has the S-N line angled far away from the horizont and the maximum cranial length is somewhat parallell to the S-N line. So, you see the cranium is tipped relative to a true horizont.
Person 'B' has the S-N line closer to the horizont and the maximum cranial length is found somewhat parallel to that.
It really isn't a matter of either tipping their heads. In fact the S point does not change that much with slight head tips which is one of the reasons Steiner used it in his analysis. (Also easier to spot on an X ray than the porion point from which they draw the Frankfort horizont.) Person 'A' does not have a 'true' horizontal FH either. Person B does.