Fig. 1From: Influence of orthodontic treatment with premolar extraction on the spatial position of maxillary third molars in adult patients: a retrospective cohort cone-bean computed tomography studyMaxillary coordinate system shown with 3 planes: horizontal(xOy), frontal(xOz) and sagittal(yOz) planes. 4 landmarks were used for setting up the system: ANS, anterior nasal spine; PNS, posterior nasal spine; Or_L, left orbitale; Or_R, right orbitaleBack to article page