Total arch maxillary distalization using infrazygomatic crest miniscrews in the treatment of Class II malocclusion: a prospective study

Objectives: To evaluate treatment effects in Class II patients using infrazygomatic crest (IZC) miniscrews (MS). Materials and Methods: A prospective sample of 25 adolescents (14 females and 11 males; mean age: 13.6 +/- 1.5 years) who underwent maxillary dentition distalization treatment with IZC MSs were recruited. Lateral cephalograms and digital models at the beginning of treatment (T1) and after Class II molar correction (T2) were obtained. To compare cephalometric and digital model changes, paired t-test and Wilcoxon test were used. A significance level of 5% was used. Results: All patients achieved Class II molar correction over a mean period of 7.7 +/- 2.5 months. The IZC MS therapy provided 4 mm of distalization; there was 1.2 mm of intrusion of the first molar with 11.2 degrees distal tipping. The maxillary incisors were retracted 4.7 mm and tipped lingually 13.4 degrees. Overjet and overbite showed a reduction of 3.6 mm and 2.4 mm, respectively. The occlusal plane rotated clockwise 2.8 degrees. The upper lip was retracted by 1 mm and the nasolabial angle increased 5.1 degrees. There was an increase in the interpremolar and intermolar distances. Conclusions: Total arch distalization of the maxillary dentition using IZC MS was effective in the treatment of Class II malocclusions.