text: If the acute inflammatory response persists, the body then proceeds to undergo chronic inflammation. During this continual and systemic inflammation phase, one of the primary driving forces is the infiltration of macrophages. The macrophages and lymphocytes induce the formation of new tissues and blood vessels to help supply nutrients to the biomaterial site. New fibrous tissue then encapsulates the foreign biomaterial in order to minimize interactions between the biomaterial and surrounding tissue. While the prolonging of chronic inflammation may be a likely indicator for an infection, inflammation may on occasion be present upwards to five years post-surgery. Chronic inflammation marked by the presence of fibrosis and inflammatory cells was observed in rat cells 30 days post implantation of a device.
  Following chronic inflammation, mineralization occurs approximately 60 days after implantation due to the buildup of cellular debris and calcification, which has the potential to compromise the functionality of biocompatible implanted devices in vivo.