Wednesday, October 19, 2011

Invisalign in Toronto- Dr. Tam Discusses Invisalign G4

In early October 2011, your Toronto Invisalign Specialist followed a program in which Invisalign announced a series of features known as Invisalign G4.  They sought to address 3 major issues that some Invisalign doctors had been having issues with.  These include:

1.  Greater root tip control for canines and upper laterals
2.  Improved predictability for upper laterals
3.  Better clinical outcomes for open bite treatments

There was a theme that Invisalign is based upon the science of orthodontics.  Namely, we have to think of a desired movement, determine a force system, and then design an appliance.  At this point, all other aligners other than Invisalign skip the middle step of determining a force system.  This is asking for failure of treatment when the proper orthodontic forces are not applied.  Anyone can make an aligner or video look good from start to finish.  The key is whether the teeth will move that way also.  Can you move roots with Invisalign?  According to the new changes, they should allow for root movement using new attachments.

In order to achieve these difficult movements, one of the newest features is to apply to force systems to one tooth.  This is in the form of attachments or a pressure point, where one feature will counteract the negative forces caused by the first.  They are supposed to allow for simultaneous movements such as extrusion and rotation, as well as translations.  There is a claim that these new attachments are more aesthetic than previous attachments, with the more gingival attachment often covered by the lip.

It was also announced that optimized attachments with G3 can now be used with precision cuts on canines.  This was not previously possible.  The cuts are not yet tested with G4 attachments, and thus cannot be used simultaneously.

Also, an update on the iOC scanner was given.

Over 1000 scanned cases have been submitted, with greater accuracy in seating, less spring, improved retention, and proper contouring around the gingiva (according to these numbers, your MCO Markham orthodontist has submitted about 3-4% of world-wide scans).  Patients have reported less saliva trapped under the plastic, likely since the aligners comform better to the teeth.  Rejections of scans to date have been virtually non-existent, since any deficiencies in the scans can be corrected easily chair-side.  Clinchecks are also back in the doctor VIP page on an average of 2 days vs 10 days for PVS impressions.

Overall, Invisalign has been very dedicated to the science of tooth movement with aligners and listening to concerns of doctors and patients.  However, remember that the most important factor in treatment is going to be proper treatment planning by your orthodontist of choice.  It is his/her job to decide exactly how the teeth will move and when to use specific features to help aid in these movements.