Molar DErotation in class II

[ArchWired28]

Apparently, rotated upper 1st molars are the cause of ~85% of all class II bites At least those mainly of a dental nature (as opposed to the true skeletal cases when small lower jaw is the cause). Since rotated molars take more space in the arch, derotating the 1st molars alone can create up to 4mm of dental class II correction.

I know that molar derotation can be achieved by proper positioning of the brackets and choosing the appropriate wires. There are certain easy techniques to tell if the molars are rotated. However, I have checked the models of my teeth taken for braces and now, and one of my molars is derotating (I can tell it is since it even looks differently) while the other does not seem to have moved a tad I of course want to know why, but perhaps nobody but my ortho will be able to answer that.

What I want to ask here, is does anybody know any specific technique(s) to have their molars derotated - in addition to wires and brackets? I can than ask my ortho if he thinks I can have anything specific done to facilitate derotation of that stubborn molar

[freysmiles]

The reason why molars become rotated with Class II cases is that the large palatal root (there are three roots on upper molars) drags along the ridge of bone that your teeth sit in and slows it down while the side of the molar towards the cheek moves a bit faster. This same principle may be why the molar isn't de-rotating as well (the roots might be near the bone cortex and moving slower).

If your molar is still Class II and you want to de-rotate it a Carriere Distalizer works extremely well. Otherwise your orthodontist can place the bracket in a new spot or actively de-rotate the tooth using a TPA.

[ArchWired28]

freysmiles
thank you very much for your reply! It is my understanding that my ortho relies on the brackets and the wire to derotate the tooth. But it has been 7+ months and it does not seem to move. Wouldn't you expect it to derotate by now? If my ortho continues to use only the fixed archwire, will it eventually derotate or will it remain rotated indefinitely? Wouldn't the thick square steel wire be better to achieve the derotation (I am now in the Australian wires whatever that is )?
Also, can you please comment on the shoe-in wire bends and how effective those are in molar derotation? My upper arch is fully bonded and perhaps Carrier distalizer is not an option, and a TPA looks too... uncomfortable

[freysmiles]

Your orthodontist will be able to get the rotation out with wires and brackets and be glad he/she is opting for that instead of using a TPA (those are uncomfortable). Sometimes teeth just move slowly so don't get discouraged.

[ArchWired28]

Thanks again, freysmiles! Your response is really helpful!

[GettingStraight]

It can take a LONG time. My upper 2nd premolars are rotated and they have been SLOW to move. One of mine took 11 months to derotate, and the other one is being even more stubborn - after 13 months still has some more to go.

[ArchWired28]

GettingStraight

it is long... Why do I read that it happens much faster, actually in 2 months in some cases. How are your teeth being derotated, with brackets and wires only?

[GettingStraight]

All my teeth have been moving slowly. Guess I'm just lucky that way

It's just been brackets, wires and metal ties instead of ligs on those teeth. No other special hardware.

[DrJasonKTam]

There are many ways molar derotation can happen. A lot of the times, it can happen with brackets and wires.

If more movement is desired, it can be helpful to bond buttons on the linguals of some of the teeth and use elastic chains or threads on the buccal and lingual. We often do this when teeth are so far rotated that we cannot get a bracket in position on the buccal of the tooth.

[ArchWired28]

There are many ways molar derotation can happen. A lot of the times, it can happen with brackets and wires.

If more movement is desired, it can be helpful to bond buttons on the linguals of some of the teeth and use elastic chains or threads on the buccal and lingual. We often do this when teeth are so far rotated that we cannot get a bracket in position on the buccal of the tooth.

Thanks Dr Tam! My molars are not that much rotated, however enough to cause a molar class II on one side. I have been watching for it to correct, but it does not seem to move I am not sure if this is normal for the molars to take that long to derotate, or if it's just the technique/force not being optimal. I am concerned that my treatment will take longer than initially planned, since I understand that there will work to be done after my molars are in the correct position and in the class I.... Thanks again!