Help with Cephalometric Analysis

[tjarrr]

Hi everyone. I had a ceph done and i am wondering whether my maxilla is recessed? My N-A perpendicular is 0.1 mm which appears to be pretty normal (range apparently is 0-2 mm), and this is one measurement used to determine maxilla position. However, my ANB is -2.5 degrees which is very abnormal (normal value is 2.5 degrees) so my measurement is 2 standard decisions below normal. My SNA and SNB values got messed up so I can't use them for reference. My Pog-N perpendicular is 2.3mm, which is one standard deviation above normal. Overbite is 0.2 mm and the normal is 2.5 mm. Gonial angle is 116; mandibular plane angle (FMA) is 19.2; facial angle (FH-NPo) is 93.3.

Can someone make a guess at whether my maxilla is recessed? What about my lower jaw? Any insight would be greatly appreciated!!

[tjarrr]

Better question: could people who have had cephs done that showed they have a retruded maxilla attach their analyses or send them to me so I could compare mine to yours? Mostly interested in what you got for the N-A perpendicular measure. Thanks!

[ditterbo]

Not many people here are versed in numerical analysis like that.. you're better off posting a ceph for a rough cut judgement.

[Eilerson]

 Your ANB angle means your maxilla is posterior (further back) to your mandible i.e. Class III malocclusion. This can be caused by a deficient maxilla or a prognathic mandible, or probably combination of both in your case.

 It's probably better that you post your own CEPH as they aren't easy to interpret, probably moreso since you don't seem to know what a standard deviation is.

[tjarrr]

Ceph is attached.  And no, those standard deviations are what is listed. The titles of the four columns are as follows: (1) my individual value; (2) what the norm value is; (3) the standard deviation; (4) my individual deviation from the norm.

[attachment deleted by admin]

[Wheatsnax]

it still looks like you are having a lot of neck extension in that ceph and it will affect your values hence the weird findings

take another one with your chin dropped and relaxed and eyes staring at the horizon

[idk]

What ceph is that? McNamara?

Also how long is your ramus? Is normal or short?

How is your overbite?

And also if you don't mind. Do you have your ricketts lateral ceph? I am very interested in comparing my values to your specifically the value that is number 27 (at least in my ceph) that relates the posterior occlusal plane to Xi (center of the ramus).

Regarding to  your main question please tell me in which ceph i can find those measurements. Rickets, mc namara or bjork jarabak? So I can go to mine or do google research to try to do some feedback.  Thanks

[idk]

Ok starting.

The NA perpendicular seems normal, but tending to retrusion. Now: if we look at the ceph xray, your skull is upward tilted. If I am not wrong, the more the skull is upward tilted with neck hyperxtension, the more the A point will appear forward to N point, yet that position of the head is NOT physiologic. So that measurement has no value. We should have the measurement taken with natural head position without neck hyperextension and eyegaze paralel to true horizontal.  It's my view that the value would be very different and probably show a maxilla retrusion. 

[idk]

Continue:

ANB. So your ANB is lower than the norm.  I did not have that ceph measurement taken it seems son can't compare. It seems that value indicates a skeletal class III. But seeing your pictures is obvious that you are not skeletal III.  Now: The AN line is not altered by head position. But the NB line is altered by head position and dental occlusion so by it self it seems that that angle is not a reliable source to adress skeletal sagital problems of the maxilla.

[tjarrr]

My head is not tilted upward. I just have a recessed forehead so it looks like that.

Facial Axis Ricketts - 92.3 degrees

[idk]

My head is not tilted upward. I just have a recessed forehead so it looks like that.

Facial Axis Ricketts - 92.3 degrees

Can you explain me what having this value lower or higher means?

If I understand, low value means CW grow pattern and high value CCW grow pattern?

[idk]

I dont understand what facial axis is related with the head being tilted or not. The flattened occlusal plane displays the tilt in my view.

Idk what your overjet is, but if you have little to zero overjet it seems like your maxilla is actually retruded and that your lower jaw has not place to ccw rotate and fit properly. So for to airway not colapse you need to tilt the head and that way your occlusal plane looks flattened, which is not normal for people with dolico/hyperdivergent grow type. If you were a brachi I would understand the flattened occlusal plane, but in this case that flattened occlusal plane is not phisiologic  in my oppinion. So the jaw ccw of your airway by means of a upward tilt of the head, that way you dont  have premature contacts in the anterior sector that you would have if the head was in properly position with bipupilar plane paralel to true horizontal.   So in order to your bipupilar align to horizontal for eyesight you need to move your head forward,  which is seen in your side picture  that I have seen in other thread.  Forward head posture implies a hyperactivity of the extensor muscles of the head.

Still pretty interested in know your values of occlusal plane to xi (center of the ramus). Could you provide me that value?

[tjarrr]

I dont understand what facial axis is related with the head being tilted or not. The flattened occlusal plane displays the tilt in my view.

Idk what your overjet is, but if you have little to zero overjet it seems like your maxilla is actually retruded and that your lower jaw has not place to ccw rotate and fit properly. So for to airway not colapse you need to tilt the head and that way your occlusal plane looks flattened, which is not normal for people with dolico/hyperdivergent grow type. If you were a brachi I would understand the flattened occlusal plane, but in this case that flattened occlusal plane is not phisiologic  in my oppinion. So the jaw ccw of your airway by means of a upward tilt of the head, that way you dont  have premature contacts in the anterior sector that you would have if the head was in properly position with bipupilar plane paralel to true horizontal.   So in order to your bipupilar align to horizontal for eyesight you need to move your head forward,  which is seen in your side picture  that I have seen in other thread.  Forward head posture implies a hyperactivity of the extensor muscles of the head.

Still pretty interested in know your values of occlusal plane to xi (center of the ramus). Could you provide me that value?

 I think the theories about head posture have much less mileage than people think they do.  This is simply the posture I was asked to assume while the x-rays were being taken and the chin rest was level with my head.  My head is not in any weird, unnatural position; again, I just have a recessed forehead so it looks like an unnatural head position.

 I'm not entirely sure what you mean by the issue with overjet, but yeah, I have a lower than normal overjet: it's 1 mm, when the norm is 2.5 mm. It's within the normal ranges though because the z score is -.6. Overbite is .3 mm and the norm is 2.5. I don't have a steep mandibular plane so I think the stuff you mention about ccw rotation does not apply here.

Unfortunately I don't have the values you're looking for, my ceph doesn't give me an occlusal plane to Xi value. As for the Ricketts facial angle value + other facial angle measures: I think those measure facial growth patterns. So an angle near or above 90 degrees= horizontal growth pattern; angle below 90 degrees=vertical growth pattern.

[idk]

Well. If you are asymptomatic and can function well with that occlusal plane and forward head posture, then it's right. Maybe your body is adapted to that occlusion.

What's the inclination of your upper incisors? Is normal or they are proinclinated?

About the overjet: If your skull rotates around a fulcrum in the upper maxillary incisors in a CW direction, eventually the change in inclination of the maxillary incisors would make premature contacts with the inferiors. Thats why your skull has to be placed in that tilted position to avoid those prematurities.  If your upper incisors are labial inclined, this would me more proof to my theory, but I don't know if that is the case.

Anyways...If you feel ok with your occlusion and head posture, then probably your organism is in it range of adapatation so no problem.  Yet still I think the maxilla lack developement.

Regarding growth pattern.. There are quite a few number of different grown patterns. 

A true skeletal horizontal pattern needs a thick and long ramus. Do you have that? I don't think so.

Your chin is retruded as well as you have a kinda convex profile. Definitely not a horizontal grower. You are not a traditional vertical one because the muscular tone is OK so you avoided an open bite.
That's my view.