150 - 200 μm

These images show the drastic differences in the size of an RBC. at 7-8 um in comparison to an osteoclast at 150-200 μm. The osteoclast is a very complex cell which begins as a single nucleus monocyte and when called to duty by cell signals differentiates into a macrophage. They generally travel in the bloodstream as monocyte and differentiate into macrophages when they reach the work site. They then further differentiate into osteoclasts which coalesce and form a multi-nucleated huge bone-eating machine. Their size can almost fill the entire periodontal ligament and explains why space in the ligament is required. Through acid and enzymatic digestion, bone is efficiently resorbed and macrophages remove the remaining debris.