Fig. 4
From: Stresses in the midpalatal suture in the maxillary protraction therapy: a 3D finite element analysis
![Fig. 4](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40510-016-0121-5/MediaObjects/40510_2016_121_Fig4_HTML.gif)
Principal Stress vector’s section. a MinPS—section position. a′ MinPS—enlarged view of the MinPS vectors’ directions. b MidPS—section position. b′ MidPS—enlarged view of the MidPS vectors’ directions. c MaxPS—section position. c′ MaxPS—enlarged view of the MaxPS vectors’ directions