Figure 2.

Ligature model of periodontal disease induces bone loss in old and young mice. A 6.0 silk suture inoculated with Porphyromonas gingivalis was tied around the second maxillary molar bilaterally (A). Sutures remained in place for 7 d to induce disease. The inoculated ligature induced significant linear bone loss, as measured from the cementoenamel junction to the alveolar bone crest, in both old and young mice (B). Mice of each age group were divided between 2 arms of the study, a disease induction arm and disease recovery arm (C). In the induction arm, the animal was euthanized after 7 d of disease induction. In the recovery arm, the ligature was removed at day 7 and the mice were allowed to recover for an additional 7 d before the animal was euthanized and tissues analyzed. PLX3397 was administered to deplete macrophages during the induction or recovery period. Non-PLX3397 groups received control chow. n = 6/group. Data presented as mean ± SD. *P < 0.05.