ABSTRACT

The aim of this prospective clinical study is to evaluate the treatment effects of the miniscrew implant supported distalization system in patients with Class II malocclusion.

The study sample consisted of 10 patients (5 girls and 5 boys) with a mean age of 14,9 years. Two titanium intermaxillary fixation screws were placed lateral to the foramen incisivum in the anterior paramedian region of the palate. Alginate impressions were taken and appliances were constructed on the model casts. The MISDS was cemented on the upper first molars, then connected to the miniscrews by means of metallic ligatures. The appliance was activated by squeezing the open coil springs. 200 g of distalization force was applied on each side. Lateral cephalometric radiographs were obtained before (T0) and after (T1) the distalization were measured. Data was analysed by SPSS.

The mean maxillary first molar distalization was 2,45 mm (p<0.05) and 1° (p<0.05) slight distal tipping accompanied distalization. Maxillary second molars distalized 4.35 mm (p<0.05) and tipped 2°(p<0.05) distally. The upper second premolars showed 3 mm distal drift following the upper first molars and tipped 2.3° distally, while 2.35 mm spontaneous distalization and 1.6° distal tipping were seen on the upper first premolars. Upper incisors were retroclined 1.45° (p<0.05), which decreased the overjet 0.8 mm.

MISDS is an efficient way of noncompliance maxillary molar distalization which results with almost translatory distal upper molar movement.