Figure 3From: Effects of crown-root angle on stress distribution in the maxillary central incisors’ PDL during application of intrusive and retraction forces: a three-dimensional finite element analysisStress distribution in PDL of upper central during application of retraction force, palatal view. (a) Stress distribution in PDL of upper central with crown-root angle of 166.7° during application of retraction force, palatal view. (b) Stress distribution in PDL of upper central with crown-root angle of 173.4° during application of retraction force, palatal view.Back to article page