Orthotown April 2020 - 32

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Fenrisúlfr
Member Since: 02/25/09
Post: 3 of 26

He has discrepancies in all three planes of space. I would begin right away, but have him
work on OH first, esp. around the L2-2. The first step would be to discuss the two possibilities:
Orthognathic surgery or premolar extractions. Non-extraction is not an option here.
Begin with RPE on the upper, to a decompensated lower arch in 21x25 SS (bypass the
2-2), so you can coordinate maxillary skeletal expansion to an accurate lower transverse. Once
the transverse has been addressed, and OH is better, you can begin leveling the L2-2 with an
intrusion arch. After the arches are leveled, aligned and in 19x25 SS, I would obtain progress
records, including a VTO and make the decision between orthognathic surgery, or the extraction
of U4s only vs. upper 4s/lower 5s. ■
2/11/2020

justinudm
Member Since: 09/29/14
Posts: 4 and 5 of 26

This is a tried and true surgery case. The L6s have buccal pits that likely have decay. I would
contact the GP about this before starting treatment.
There is an 8mm Class II skeleton due to a mandibular retrognathia. These types of Class II
skeletons do not grow with functionals. That's why I say surgery. Without measuring out the
crowding, I cannot know if it's lower 4s or L5s that need to be extracted to establish ideal lower
incisor position. But this is a hyrax, extraction of two lower premolars and a BSSO mandibular
advancement possible two-jaw advancement. I would need a smiling profile picture to know if
two-jaw surgery is indicated.
This cannot in my opinion be treated without surgery. A suitable secondary option, if parents
refuse surgery, is to expand the upper some, take lower teeth out and leave overjet. But most
people don't want to do that.
[I like the upright position of incisors to the face so I don't really wish to retract them.]
The LL1 already has a mucogingival defect, no way a Class II corrector/dental mover should
be placed that can further move this tooth out of bone. Once again, I ask for you to post a
similar case you have treated in the manner you describe, with before and after records, including
superimposed cephs. Because if you are doing something that I cannot, I would love to learn. ■
2/11/2020

3mortho
member since: 11/18/07
post: 7 of 26

Thank you for your comments. Can you please elaborate on your opinion that functional
appliance would not be an option in this case? I do not think the patient will accept the idea of
surgical treatment. ■

2/11/2020

Fenrisúlfr
Member Since: 02/25/09
Post: 8 of 26

justinudm
Member Since: 09/29/14
Post: 9 of 26

A functional will blow the lowers out of the bone. With tissue this friable, it is simply a very
bad idea. ■

2/11/2020

OK, here is my perspective. This is how my thinking on Class II skeletons evolved over time.
I have said this before, but functional appliances do not grow jaws; they move teeth through the
jaws. I discovered this after the first 18 months of private practice when I started to superimpose
my before-and-after cephs. I then went back and reread all the ABO board articles and discovered
a disturbing trend. All these articles used A-point and B-point to prove skeletal growth. This is an
error in thinking, because A-point and B-point move with the tipping of the U/L incisors. A-point
moves back as U2-2 move back;. B-point moves forward with procliniation of L2-2. What these
authors are doing is using dentoalveolar landmarks to prove skeletal change. This makes no sense.
Instead, bony landmarks like pogonion and ANS/PNS should be used. When you look at the tables
and raw data on these same studies, they show 1mm of change in pogonion. Well, that's within
the realm of measurement error.
So, next I reread the famous meta-analysis showing that 3-3.5mm of jaw growth is achievable
with functionals. The issue here is that the authors of the accepted articles for the meta analysis

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