Figure 24. Day 3: blood coagulation, inflammatory cells, granulation tissue At the end of this initial healing period, small segments of the coagulum are replaced by a highly vascularized granulation tissue and an inflammatory cell infiltrate that is stained dark red/blue.

  Figure 23. summary of biological events on third day after extraction On day 3, the socket is filled with a blood coagulum comprised of red blood cells and platelets trapped in a fibrin network together with isolated inflammatory cells such as neutrophils. Close to the bundle bone, mesenchymal cells, severed periodontal fibers, and dilated vascular units can be observed.