Skeletal and dental changes following the use of the Frankel functional regulator

The purpose of this study was to assess the relative contributions of skeletal and dental components in correction of Class II division 1 malocclusions when treated with Frankel's functional regulator (FR). This was a retrospective study involving analyses of pre- and post-treatment cephalograms of 63 Class II division 1 patients treated with the FR to demonstrate the relative maxillary, mandibular, incisor, and molar movements during treatment compared with normal growth within a control group of untreated 39 Class II division 1 cases drawn from the same demographic population. All cephalograms were digitized and subjected to a Pitchfork analysis, which measured individual anteroposterior skeletal and dental changes during the period of study. It was shown that the FR was effective in treating Class II division 1 cases with the studied group being corrected to a clinically acceptable overjet and overbite of 2-3 mm. The majority of the correction came from dental movements, the most significant being the retroclination of the upper incisor teeth (mean 4.1 mm, 95 per cent CI +/- 0.44) and proclination of the lowers (mean 2.2 mm 95 per cent CI +/- 0.57). As regards skeletal correction, the most significant contribution was the restraint of normal maxillary forward growth (mean -0.2 mm, 95 per cent CI +/- 0.62) with forward mandibular growth not being a significant factor.