Bone resorption assay
Functional evidence of osteoclast formation was determined via a lacunar resorption assay system using cell cultures on dentine slices as previously described(17). Cells were removed from the dentine slices by treatment with 0.1 M ammonium hydroxide. The dentine slices were washed in distilled water and ultrasonicated to remove adherent cells, then stained with 0.5% (v/v) toluidine blue to reveal areas of lacunar resorption, and examined via light microscopy.