A new fixed interarch device for Class II correction.

JCO/JANUARY 2003 F devices are increasingly being used for molar distalization in Class II treatment because they eliminate the need for special patient compliance. These appliances fall into two main categories: intra-arch (such as the Distal Jet,* Jones Jig,* and Hilgers Pendulum**) and interarch (such as the Herbst*** and active springs). The spring appliances can be further divided into cantilever types (such as the Jasper Jumper* and Bite Fixer**) and telescoping types (such as the Eureka Spring**** and Twin Force†). Recently, two new fixed interarch spring devices have been introduced for Class II correction: the Forsus Nitinol Flat Spring‡ (a cantilever spring) and the Forsus Fatigue Resistant Device‡ (a telescoping spring). This article describes the use of the Forsus Nitinol Flat Spring (Fig. 1).