The aim of this study was to evaluate the effects of a magnetic appliance, MAD IV, on the treatment of anterior open bites in growing patients. The study material included the lateral cephalograms and hand-wrist radiographs of 16 patients who had an anterior open bite malocclusion. The radiographs were taken at the beginning (T1) and at the end of observation period (T2) and at the end of MAD IV application (T3). At the beginning of the study, the mean age of the subjects was 11 years two months. To define the direction of facial growth, the patients were first observed for nine months without any orthodontic or orthopedic approach. At the end of the observation period, patients who had shown a vertical growth direction, resulting in an increase in open bite, were given an MAD IV appliance and were instructed to wear the appliance 18 hours a day for 7.5 months. Thirty-two different parameters were evaluated from the lateral cephalograms. Paired t-tests were used for statistical evaluation of differences that occurred during the periods and between the periods. During the observation period, the patients continued their mandibular posterior rotation resulting in an increase in lower facial height (P < .001) and an open bite (P < .01). During the treatment period, the patients showed an anterior mandibular rotation with statistically important decreases in lower facial height and open bite (P < .001). In the treatment of anterior open bite with the MAD IV appliance, skeletal changes played a role along with dental and dentoalveolar effects.