Search

The most common extra-alveolar sites for miniscrew placement are the infrazygomatic crest region (IZC) and mandibular buccal shelf region (MBS). The aim of the study is to determine the amount of distalization achieved with IZC and MBS mini screws, and if it has any correlation with the growth pattern. Pre-treatment scan (T1) and post-distalization (T3) scans of 30 patients were taken in whom en masse distalization with either IZC or MBS mini screws or both was achieved. T1 and T2 scans were then superimposed on OrthoAnalyzer software using landmark reference points on maxilla and mandible and assessed for the amount of distalization. The following statistical tests were conducted: Kappa statistics to assess the intra-observer reliability, Descriptive statistics for the amount of distalization by both IZC and buccal shelf mini screws, and its correlation with varying growth patterns and gender. The mean distalization achieved with IZC anchorage was 3.491 ± 0.471 mm and the mean distalization achieved with buccal shelf mini screw anchorage was 4.412 ± 0.904 mm. A weak negative correlation between growth pattern and amount of distalization was observed (r=-0.379; p=0.007). The present study suggests that both infrazygomatic and buccal shelf anchorage for arch distalization in borderline surgical class II and III cases are effective modalities. It also suggests that the skeletal facial pattern may favorably influence the amount of distalization in hypodivergent facial type, especially with MBS anchorage. [ABSTRACT FROM AUTHOR]