Fig. 3From: A comparison of three-dimensional stress distribution and displacement of naso-maxillary complex on application of forces using quad-helix and nickel titanium palatal expander 2 (NPE2): a FEM studyEvaluated landmarks: point A, point near incisive foramen; point D, point near palatine bone; point B and C divide the A–D line into three equal partsBack to article page