Evaluation of Safe Zones for Miniscrew Placement in Class II Patients with Different Vertical Skeletal Patterns

SUMMARY The aim of this study was to compare interradicular space, buccolingual alveolar distance, and cortical bone thickness in skeletal Class II patients with long face and short face. The gender differences were also evaluated. 30 CBCT images obtained from patients with skeletal Class II malocclusion were divided into two groups according to patients’ facial type. 15 patients (9 girls, 6 boys) with short face comprised SF group and 15 patients (6 girls, 9 boys) with long face comprised LF group. Interradicular space, buccolingual bone distance and cortical bone thickness between first and second molars, second premolar and first molar, first and second premolars were examined at four different depths from the alveolar crest. LF and SF groups and gender differences were compared with MannWhitney U test. Interradicular space between mandibular molars and mandibular premolars were smaller in LF group and cortical bone was thicker at some sites in SF group. Girls’ buccolingual bone distance was lower than boys’ in both maxilla and mandible. Mandibular interradicular space is shorter and cortical bone is thinner in long-faced skeletal Class II patients. Sex only affects the buccolingual bone distance and it is shorter in girls.