What's a normal bite ?

Message

#1 Post by **Relentless2** » Mon Aug 28, 2006 6:40 pm

here's the rundown...

I had class II overjet at 6.5 mm and needed a wider upper arch, plus redressing of some slightly inward slented lowers... I've been braced with Daemon 2 on March 21st, 2005.

I've had 2 elastics to correct the class 2 for over 6 months now. now I am supposed to have them removed on Oct 12th....

now I'm wondering what really *is* a normal smile.... let me explain...

when I bite down hard, and I make my back teeth really connect (like when I an chewing), there is still a 4-5mm overjet, but my cannines are perfectly aligned (slightly touching the lowers).

when I superpose my front teeth or nearly so, the back aren't touching... is this normal ?

I'll try to post some pictures... but my girlfriend is gone for the week and I can't find where she put the camera !!

thanks for your opinion, 'cause I'm wondering if it's really time to remove them, and to what extent the retainer can correct this...

#2 Post by **Relentless2** » Mon Aug 28, 2006 7:54 pm

wow ! thanks for the info ! I can't say I understand all the terms, but from what I read the alignment seems ok, but I still overjet more than 1-2mm... I'll post pictures tomorrow...

thanks !

#3 Post by **SDFD TSchott** » Mon Aug 28, 2006 8:05 pm

I'd just have to say Meryaten You've done a great job at an awesome description of the different classes!

SDFD TSchott

#4 Post by **rsprouse** » Mon Aug 28, 2006 8:10 pm

A Class I molar relationship has the front cusps of the upper molar resting when the bite is fully closed within the fissure (not sure if that's the right term, but...) of the corresponding lower molar.

It is actually the fossa that you are referring too. Molar relationship is determined by the location of the mesial buccal cusp of the maxillary first molar in comparison to the buccal groove. It is normally the desired out come of orthodontic treatment because it represents the normal sagital relationship of the posterior teeth. Although it is still a malocclusion at times. So in english it is the front outer cusp of the upper first molar fitting in the mid point groove thing on the outside of the lower first molar.

The upper canines should be between the lower canine and first premolar:
The upper canines should come outside of the lowers and vertically overlap them by a small amount.

Not always, but that is the typical location to achieve canine guidance which is a desired distribution of force upon functional load.

The Class I incisal relationship has the upper front incisors just in front (1 - 2 mm, I believe) of the lower front incisors. The upper front teeth should overlap the lowers by a small amount (sorry I forget the measurement in mm or as a percentage of the tooth size) - too much and there is a deep bite.

You are actually referring to "division", and it has to do with how the maxillary incisors flare in relation to the mandibular incisors. Division 1 has a nice \ shape, whereas Division 2 is a more | (straight or even negative tilt) to the maxillary incisors.

Lastly, of course, in the ideal occlusion the midlines (top and bottom) will line up.

Not always true, the only thing that it really matters for is aesthetics. There is not a functional requirement to having the midlines line up.

Occlusion is a very in depth and difficult subject. If you talk about it in a room with 10 Dental Professionals then you will likely get 7-8 different opinions. You take a more than a year of class in most Dental schools on occlusion and even more if you become an Orthodontist. So this is a basic explanation of a deep subject.

So the answer to the original question is a normal bite is what works for you. Hopefully it is something that is bilaterally balanced with anterior and canine guidance that will not cause any excess wear and tear from normal use.

Best,
Rory

#5 Post by **rsprouse** » Tue Aug 29, 2006 5:21 am

It goes back to the 10 Dentists in a room comment and would be handled on a case by case and a per person opinion basis. There is no definitive answer like "Class I molar relationship is the most important factor". It depends on wear patterns, present teeth, bone levels, etc. Proper Class I molar relationship allows for better intercuspation on function allowing the patient a more comfortable and useful bite. It is typically more desirable to have and a slight priority over correcting a minor overjet or overbite. Overbite and overjet typically come into play with anterior guidance (shifting your mandible forward). The human body is pretty amazing at adapting and you would be pretty surprised at some of the crazy bites I have seen in people that have perfectly healthy TMJ's and oral cavities. Kinda makes you wonder if Ortho is really necessary

(it is!)

Best,
Rory

#6 Post by **Chris** » Tue Aug 29, 2006 9:06 am

The human body is pretty amazing at adapting and you would be pretty surprised at some of the crazy bites I have seen in people that have perfectly healthy TMJ's and oral cavities. Kinda makes you wonder if Ortho is really necessary (it is!)

Best,
Rory

Ok, I want my money back!

#7 Post by **wiredkitty** » Tue Aug 29, 2006 10:30 pm

Thanks Meryaten for putting those pictures of the classes. I had no idea what class I was but think I must be Class II - which is why I also need the surgery to extend my lower jaw (to make my profile look more like class I

)

#8 Post by **Relentless2** » Wed Aug 30, 2006 8:12 pm

Ok thanks for all the info !!! I'll try to post pictures tomorrow so as to get some feedback from you, which I would very much appreciate !!!

thanks !

#9 Post by **rsprouse** » Thu Aug 31, 2006 4:27 am

I started out with a class II (no clue which div). Here are my initial X-rays, for what it's worth:

Looks like Division I. Usually I see a brain in lateral ceph's, where is yours?

(jk!!)

Best,
Rory

#10 Post by **Relentless2** » Thu Aug 31, 2006 4:54 pm

Ok, FINALLY ! here are some pictures

They are all when biting down.... so, what do you all think of the overjet ? I think overall I'm very close to completion, no ? I should be off Oct 12th !
I have RAM elastics, (on for 8 months now)... didn't need the 3M Forsus (yes !)

Thanks !

#11 Post by **jennielee81** » Thu Aug 31, 2006 5:49 pm

It's hard to see the relationship between your uppers and your lowers on the side, but from the front teeth it looks like you've got only a few mm's to go.

You've come a long way!

If you can get SIDE pix without your elastics (we wont' tell your ortho you took them out...honest

) and with your cheek pulled back, we could see where your cusps line up.

Again, you've come a LONG way so far!!

#12 Post by **Relentless2** » Thu Aug 31, 2006 7:15 pm

Here are side pics !!! OMG my face is distorted on those pictures !!! damn camera ! lol

so how does it look ? should I make the Oct 12th deadline or is it just a tactic that the doc uses on all his patients ?

I already have my appointment for my retainer on the 26th though... does this sound fishy ? My ortho is *very* experienced, so I doubt he'd let me go half done... but I really want some 2nd opinions !

Thanks !

#13 Post by **jennielee81** » Fri Sep 01, 2006 4:29 am

They look real good from the side (from this untrained eye). Your uppers look like they're where they should be. In relationship similar to that posted by Rory and Maryaten and that which my ortho is trying to achieve with my bite.

I can't say anything about your deadline though. When ever I think I've gotten to one in my treatment, there's a whole new goal to achieve and months to wait!

Best of luck to you!!

#14 Post by **Relentless2** » Fri Sep 01, 2006 4:58 am

I have to admit that this last month I've really felt things move into place.. my bite is more even and I get really good contact point all across.... I am just wondering about the fact that my fronts arent nearly touching, while at the same time the molar relationship is good and the two arches are nearly perfect !

#15 Post by **jennielee81** » Fri Sep 01, 2006 5:44 am

maybe they'll tilt the top teeth in a bit or the lowers out???

My front, top teeth connected with my lowers before my bite has finished moving back so he's tilting them (top) out to allow for this.

My daughter's ortho didn't bother to do any of that. He just did the best job he could witht he bite and left the "overhang"...