Open the Bite with Reverse- Curve Archwires?

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trang le:
I had a patient with deep bite and excessive soft tissue show after alignment. Now, patient is 13 yr.old, female. Now I  would like to intrude the maxillary anteriors with the reverse curve archwire. This is OK or not? Please help me. Thanks a lot!

These are photos of her.


















DMcGann:
I am NOT the guy to ask about reverse curve archwires.  I used these about 20+ years ago and did not like the results I was getting, so NOT taught in POS. You can use these products if you understand what you are using, (not sold at PDS), so here is a discussion of Reverse curve archwires so I can go on record of what happens and why.
1. the archforms will NOT be what you have diagnosed for your case, you have to accept whatever shape is being sold. All the archwires (nickel-titanium) will be in a gauge that will change the archform...so be sure to use upper and lower to avoid arch coordination problems.
2. Upper arch: incisors feel intrusive force and the wire has lingual root torque. This will procline the upper incisors until you reach the advancing limit...never will get there especially with the lingual root torque added to the archwire...so do not worry about the size of the wire doing much for you. can use round wire and same. will this force intrude incisors to reduce gingival display? I would say NO, but would welcome someone sending me a ceph overlay and photo documentation that it happened. Gingival display is corrected in POS using skeletal anchorage (very reliable).  Bicuspids feel extrusive force, that will make the mandible open, swing down and back, increasing class II.  Molars...well depending on how big your arch is, if you extracted bicuspids are not, and where you cut the archwire, the molars would feel an intrusive force...hmmm, intrude molars to open the anterior deep bite...inconsistent.
3. Lower arch:  force is applied down on the lower incisor...tipping it forward until you reach the advancing limit of your wire size+ bracket torque combination. this is generally not good, especially in class II cases where you want to retain overjet. There is an extrusive force on the bicuspids, opening the bite (mandible swings down increasing class II).  This bicuspid extrusion is considered in ortho to be unstabile...muscles/bite will push the bicuspids back down. Actually, in tight muscle patients, bicuspids probably will not even extrude.
4. what you gain in reverse curve nitie will be lost when you engage 19x25ss, unless of course you reproduce the shape to that wire. Then maybe lost in finishing wire?

vasquezdds:
Did you extract teeth? if yes at this point you will be better off repositioning bracket to open bite, if you use reverse curve is not a stable movement and  Dr McGann explain 4. what you gain in reverse curve nitie will be lost when you engage 19x25ss, unless of course you reproduce the shape to that wire. Then maybe lost in finishing wire?

trang le:
Thank you so much...much for your help. Dr DMcGann.
Thank you vasquezdds. However I wonder what should I do now? Should I will be off repositioning brackets to open bite? or  should I use the fixed functional appliance " Forsus" to move the mandible forward. That mean: At first,  I would like to reduce overbite and overjet  because patient with chin retruding and CS4 stage (after clinical examine and ceph analysis). Then I think I will  place minivis  to intrude the maxillary teeth. But, I don't know this plan is OK or not. It seem too complicate...So plesase show any my mistake in my plan....
 At present,  I have changed to the 18x25 heat cool archwire for torque adjustment and I am waiting for....the advices.

DMcGann:
Trang Le, seems that you are all over the place, shooting arrows in the dark hoping they hit something. Waiting for alignment to make treatment decisions on how to correct the class II and how to correct the gingival display. You need to spend MUCH MORE TIME in the initial diagnosis, identifying what you need to correct, what you are NOT going to correct, and the methods you plan for your treatment to reach the final goal.  What is your 'mistake'? poor diagnosis and planning.
   For instance, I am certain the gingival display was present BEFORE alignment. I am sure there was class II in the posterior consistent with the amount of anterior overjet you see now.  If you were planning to correct the gingival display, then you needed to decide BEFORE the first bracket is placed how you were going to fix this...and if you were not going to correct it, then include in the agreement with the patient that you were NOT.  Seminar 1.
   I am certain this cannot happen to you if you followed the REQUIREMENT of having a dental vto of your treatment decision. That is the golden key that you are searching for. It is right in front of you, but you have to control your wandering mind.
      You have NOT shown us any documentation (except ceph) of the class II posterior that is associated with the overjet. PLEASE stop what you are doing now, take new study models, and make NEW Dental VTO predictions of where you are going...are you distalizing the upper arch, are you using class II elastics, do you need to extract? Get a dental vto of where you are going (a new treatment decision), telling the patient that now that the teeth are straight, you can really see what you are doing and will make the best decisions. If you plan to intrude (not sure you have those skills and will likely end up with a big anterior open bite in this case), make a skeletal anchorage vto of how much you plan to intrude and if that is going to even correct the gingival display, adding to your documentation the 'resting upper lip' to the upper incisor to help in making your treatment decision.
    Overall, it appears to me that you need to submit this case with the records I have suggested, and other cases, to POS instructors to get a comprehensive diagnosis and treatment plan. Diagnosing your cases 'on the fly' on this Forum is just not the way to do it. There is a fantastic resource of knowledge that you can use to put these cases together...but you have to use it. On this forum, we work with incomplete information.  We do NOT teach "minivis", do not teach reverse curve archwires, and do not teach "forsus". I would suggest you stay within the POS system, where we know you will be successful.  Go in these directions and you are 'on your own'. 


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