Here we are with our first info letter of 2019. I will try in the coming year to publish 1 or 2 info letters per month. In our last info letter of 2018, we discussed progressive torque in the posterior area of the arch. This time, we will look at ways to torque a single tooth. If the clinician decides at the beginning of treatment that a certain tooth needs more or less torque than other teeth, he may decide at bracketing to bond that one tooth with a bracket with a different torque, example: an upper lateral with a palatally positioned root can receive a bracket that has a negative torque to promote buccal root torque. This will help proper root positioning with the progression from smaller to bigger wires but it does not guaranty 100% of correction. Often additional torque will have to be added directly to the wire for that specific tooth. The wire has to be of metallurgy and a shape that makes it possible to torque, rectangular either SS or TMA. To do that modification, special pliers make it easier. You can use a combination of a key and plier (this system is specific to a wire size which makes it less versatile, Figure 1) or a set of Rose torquing pliers (Figure 2). Deliver the torque in in small increments and in a repetitive way over 2 or 3 visits spaced at 3-4 weeks intervals until you get a slight overcorrection. Remember that slower is better to avoid overpowering the root.
Figure 1. Figure 2.