LOWER MOLARS

Lower first and second molar tubes

The lower first molar has -20° of torque and the lower second molar has -10° of torque. They have zero offset and zero angulation. As with the uppers, they have a funnel-shaped entrance, for easy wire placement.

Mini lower second molar tubes

Full size lower second molar tubes are used to correct difficult rotated or tipped teeth, but in many treatments the mini second molar tube is preferred. Despite its small size it provides good tooth control in routine cases. It is more comfortable for the patient than the full size tube, with fewer interferences and it became available in late 2018.

Treating to a Class II molar relationship

When treating to a Class II molar relationship, the lower first molar tubes are often used in the upper arch on the contralateral side (see the ‘Fundamentals of Orthodontic Treatment Mechanics’ page 61). Thus the lower right tube can be used on the upper left molars, and the lower left tube can be used on the upper right molars. Some orthodontists use normal upper molar tubes to achieve most of the tooth movements, and then to switch to lower first molar tubes for finishing. Others use lower first or second molar tubes in the upper from the outset when treating to a Class II relationship.