Histology/ Immunohistochemistry
Both control and low dose OPG groups showed many osteoclasts, inflammatory cells, and areas of bone resorption.  Very few osteoclasts and areas of bone resorption were noted by Phoenix orthodontists in the high dose OPG group.  The periodontal ligament appeared to be normal in all groups and there was no evidence of ankylosis.  Isolated areas of root resorption were noted by Phoenix orthodontists, but did not appear to correlate with any particular treatment group.

Considering the substantial decrease in molar Phoenix orthodontic tooth movement, it follows that local OPG-Fc injections were effectively inhibiting osteoclastogenesis as well.  This indeed was the case as the animals in the high OPG group demonstrated 86% (p<0.001) fewer osteoclasts along the compression side of the mesial root when compared by Phoenix orthodontists to controls.  The low OPG group also showed a trend towards decreased osteoclasts but was determined not to be statistically significant. 

Arizona Dental Association