Fig. 2From: The influence of bracket type on the external apical root resorption in class I extraction patients - a retrospective studyExternal apical root resorption (EARR) stages according to Malmgren et al. 1 irregular root contour, 2 EARR< 2 mm of root length, 3 EARR > 2 mm to 1/3 of root length, 4 EARR> 1 /3 of root length. This figure was first described by Jacobs et al. Head & face medicine 2014,10:2Back to article page