Comparative evaluation of clinical efficacy of two class II correctors in treatment of skeletal class II malocclusion. A randomised controlled trial.

Various removable and fixed functional appliances are used for correction of skeletal Class II malocclusion with retrognathic mandible in growing patients. In patients who report after the pubertal growth spurt or during the late stages of puberty with minimal growth left, fixed functional appliances are a treatment of choice. They are often called "non-compliant Class II correctors" as they require minimum patient co-operation unlike removable appliances. The Forsus FRD (3M Unitek Corp., Monrovia, Calif) is one of the most commonly used fixed functional appliance for correction of Class II malocclusion. But it is often associated with limitations like frequent breakage of canine brackets and soft tissue lacerations. It is available in various sizes, hence a large inventory must be maintained and chairside time is increased as correct size for individual patient needs to be selected. The PowerScope 2 (American Orthodontics, Sheboygan, Wis) is the latest addition to the orthodontist’s armamentarium. It comprises of several modifications in the original PowerScope to deliver latest, simple and efficient Class II correction. PowerScope 2 features a stronger wire attachment nut and visual activation indicators. It is available as a one-size-fits-all appliance, preassembled with attachment nuts for quick and easy chairside application. It provides a wire-to-wire installation with attachments placed mesial to the first molar in the maxillary arch and distal to the canine in the mandibular arch. Apart from a few case reports and clinical studies, literature evaluating the treatment efficacy of PowerScope and comparing with other fixed functional appliance like Forsus FRD is limited and at present there is no published study on the latest generation PowerScope 2. Thus, the purpose of this study is to evaluate the clinical efficacy of PowerScope 2 appliance in the treatment Skeletal Class II malocclusion and compare with Forsus FRD. The null hypothesis is that there is no significant difference in treatment effects between PowerScope 2 and Forsus.