How to Control Open Bite Tendencies with Fixed Appliance Therapy

In the old days of orthodontics, the rule for patients who were vertically challenged was to not bracket the second molars.  Bracketing the lower 7s especially was viewed as a way to open the wedge and create a true open bite in a susceptible patient.  This approach was clearly a compromise since not bracketing the 7s allowed them to "wander" and sometimes resulted in a weird final occlusion.

The current approach is the opposite.  In general, you want to bracket the lower 7s as soon as possible.  Uppers also if they are available.  Then if you fear opening the bite is a possibility, you place a bonded bite turbo on the buccal cusps of the lower second molars.  If the lower 7s are not available, you can do the same thing with the last tooth in the lower strap up, the first molar, and then duplicate this when the lower 7s erupt.

At the same time (first or second visit) you ask the patient to wear vertical elastics (deltas) from the upper 3s to the lower 3s and 4s.

The idea is to prevent bite opening by keeping the molars intruded and supplementing the action of the masticatory muscles with elastics.

Finally, when bracketing the upper second molars, be very careful about accidentally extruding the 7s.  This is best accomplished by setting the bracket height to no more than 2 mm below the cusp tip. Rick McLaughlin calls this approach "hanging the bracket in space" since it seems that it is barely on the tooth.

Please feel free to comment or ask questions below.