The purpose of this study was to evaluate the effects of a functional appliance (the R-appliance) on Class II division I vertical growth pattern patients with mandibular deficiency. Twenty patients (13 girls and 7 boys) with a mean age of 10.6 (SD 0.8) years were treated with R-appliance for 16 (SD 0.4) months. All patients had Class II division 1 malocclusions due to mandibular deficiency and were vertical growers. Lateral cephalograms obtained at the beginning (T1) and at the end (T2) of the study were analyzed. Paired t-tests showed that SNB significantly increased from 72.8° (SD 2.2°) to 76° (SD 1.8°) (P<0.001) after treatment. The incisor mandibular plane angle (IMPA) significantly decreased and Jarabak index increased for 1.7% (SD 2.5%) (P<0.007). R-appliance was successful in moving the mandible forward in vertical growth pattern patients without proclination of the lower incisors.
Keywords: Functional Appliance, Class II Division 1, mandibular deficiency, R-appliance, vertical growth pattern
Authors: Abdolreza Jamilian, Rahman Showkatbakhsh, Minoo Alipanahi, Letizia Perillo