*4.5. Bone Resorption Assay*

Here, 5 <sup>×</sup> <sup>10</sup><sup>4</sup> purified human CD14<sup>+</sup> monocytes were seeded on dentine slices (IDS, Gaithersburg, MD, USA) in 96-well plates containing a-MEM with 10% FBS and M-CSF (20 ng/mL) for 72 h. The cells were subsequently incubated with RANKL (100 ng/mL) and TNF-α (100 ng/mL) to induce osteoclast differentiation. At day 13, dentine slices were imaged using a bright filed microscope (Leica DM2500, Wetzlar, Germany). The Bone resorption pits were calculated using ImageJ software (NIH, Bethesda, MD, USA) from four randomly selected HPFs.
