The data in Figure 2 were further analyzed to assess the differences between AltrX and AOX via rank order (A, B), and to define the relative bone osteolytic:osteogenic potential of both particles via linear regression (C,D). The results confirm that AOX particles stimulate more bone resorption and new bone formation versus AltrX (p<0.002 via Wilcoxon signed rank test). The results also demonstrate that osteoclast-osteoblast coupling is virtually perfect in AltrX treated calvaria (Slope=0.97, R2=0.7015, p<0.0001). While this response was more variable in AOX treated mice, the results demonstrate that these particles stimulate more bone formation than bone resorption as indicated by the positive slope (Slope=1.13, R2=0.2160, p<0.001).