chaPter 9 Effects of Implant on the body: Biocompatibility 9.1 Local Effects 9.1.1 Definitions 9.1.2 Processes of healing 9.1.3 Acute vs Chronic Inflammation 9. 1.4 Phagocytosis(Small Particle Disease) 9.2 Systemic Effects 9.2.1 Migration of Molecules and Particles: Lymphatic System 9.2.2 Immune Response 9.2.3 Carcinogenicity
CHAPTER 9 Effects of Implant on the Body: Biocompatibility 9.1 Local Effects 9.1.1 Definitions 9.1.2 Processes of Healing 9.1.3 Acute vs. Chronic Inflammation 9.1.4 Phagocytosis (Small Particle Disease) 9.2 Systemic Effects 9.2.1 Migration of Molecules and Particles; Lymphatic System 9.2.2 Immune Response 9.2.3 Carcinogenicity
9.1 LOCAL EFFECTS 9.1.1 Definitions Healing Process of restoration of injured tissue Healing by First Intention(also referred to as primary and direct healing Restoration of continuity of injured tissue without the intervention of granulation tissue Examples are the healing of a scalpel incision in soft tissue or the healing in the very narrow gap (perhaps 2 cell diameters, 20 m) between the fragments of a fractured bone that have been re- approximated Healing by Second Intention: Healing involving granulation tissue filling the gap(defect)in the injured tissue Inflammation Dorland's dictionary definition and Pathologic Basis of Disease) A localized response elicited by injury or destruction of vascularized tissues, which serves to destroy, dilute, or wall off (sequester) both the injurious agent and the injured tissue. It is characterized in the acute form by the classical signs of pain( dolor), heat(calor), redness(rubor) swelling(tumor), and loss of function(functiolaesa). It is caused by injurious agents: biological agents(bacteria), physical agents(heat and mechanical trauma), chemical agents(small toxic molecules and immunogenic macromolecules). The role of inflammation is to contain the injury and facilitate healing. Unresolved inflammation can be harmful The end result of healing is scar Regeneration The end result of healing is tissue similar to the original tissue A semi-solid mass of blood platelets and blood cells in a fibrin matrix
9.1 LOCAL EFFECTS 9.1.1 Definitions Healing Process of restoration of injured tissue. Healing by First Intention (also referred to as primary and direct healing): Restoration of continuity of injured tissue without the intervention of granulation tissue Examples are the healing of a scalpel incision in soft tissue or the healing in the very narrow gap (perhaps 2 cell diameters , 20 m) between the fragments of a fractured bone that have been reapproximated. Healing by Second Intention: Healing involving granulation tissue filling the gap (defect) in the injured tissue. Inflammation (Dorland's dictionary definition and Pathologic Basis of Disease) A localized response elicited by injury or destruction of vascularized tissues, which serves to destroy, dilute, or wall off (sequester) both the injurious agent and the injured tissue. It is characterized in the acute form by the classical signs of pain (dolor), heat (calor), redness (rubor), swelling (tumor), and loss of function (functiolaesa). It is caused by injurious agents: biological agents (bacteria), physical agents (heat and mechanical trauma), chemical agents (small toxic molecules and immunogenic macromolecules). The role of inflammation is to contain the injury and facilitate healing. Unresolved inflammation can be harmful. Repair The end result of healing is scar. Regeneration The end result of healing is tissue similar to the original tissue. Clot A semi-solid mass of blood platelets and blood cells in a fibrin matrix
Coagulation The process of clot formation. Hematoma A localized blood clot in a tissue or organ due to a ruptured blood vessel Thrombus vesse,, An aggregation of platelets and fibrin with entrapment of cellular elements within a blood frequently causing vascular obstruction Hemorrhage Bleeding Hemostasis Arrest of bleeding
Coagulation The process of clot formation. Hematoma A localized blood clot in a tissue or organ due to a ruptured blood vessel. Thrombus An aggregation of platelets and fibrin with entrapment of cellular elements within a blood vessel; frequently causing vascular obstruction. Hemorrhage Bleeding. Hemostasis Arrest of bleeding
9.1 LOCAL EFFECTS: PROCESSES OF HEALING 9.1.2 Processes of healing Inj Biological Agents Microbial infection Chemical Agents Physical Agents Therma Electrical Mechanical Trauma urge Implant movement Features of healing End result Similar to original tissue Regeneration pall Size of wound No/minimal tissue destruction Resolution Small wound(e. g, incision) Healing by first intention(primary or direct healing) arge Healing by second intention(healing with granulation Vascularity Vascula Inflammation precedes repair or regeneration Nonvascular No inflammation No healing(cornea, meniscus, articular cartilage), regeneration(epidermis), or repair(?) Time Early(e. g, due to surgery) Acute inflammation Late(e. g, due to persistence Chronic inflammation of"injury"associated with presence of an implant) Predominant Cell Types Acute PMN, Leukocytes, Macrophage, Endothelial, Fibroblast Chronic Macrophage, MFBGC, Fibroblast Repair vs. Regeneration
9.1 LOCAL EFFECTS: PROCESSES OF HEALING 9.1.2 Processes of Healing Injurious Agents Biological Agents - Microbial infection Chemical Agents Physical Agents - Thermal - Electrical - Mechanical Trauma Surgery Implant movement Features of Healing End Result Similar to original tissue Scar Size of Wound No/minimal tissue destruction Small wound (e.g., incision) Large Vascularity Vascular Nonvascular Time Early (e.g., due to surgery) Late (e.g., due to persistence of "injury" associated with presence of an implant) Predominant Cell Types Acute Chronic Repair vs. Regeneration Regeneration Repair Resolution Healing by first intention (primary or direct healing) Healing by second intention (healing with granulation tissue) Inflammation precedes repair or regeneration No inflammation No healing (cornea, meniscus, articular cartilage), regeneration (epidermis), or repair (?) Acute inflammation Chronic inflammation PMN, Leukocytes, Macrophage, Endothelial, Fibroblast Macrophage, MFBGC, Fibroblast
9.1.3 Acute Vs Chronic Inflammation 9.1.3.1 Acute Inflammation Comprises cellular processes, soluble mediators, and vascular changes occurring immediately following injury to vascular tissue and is of relatively short duration(from a few minutes to a few days). The classical clinical signs are: heat, redness, swelling, and pain. In many cases function of the tissue is compromised 9.1.3.2 Chronic Inflammation that cell types and activities associated with a persistent injury or permanent implant, that could continue for months or years 9. 1.3.2.1 Synovium The chronic inflammatory tissue bordering an implant often has the cell composition(macrophages and fibroblasts) and arrangement(cells in mono-or multiple-layer)consistent with synovium, The tissue that lines joints and encapsulates fluid-filled sacs(bursae) 1.3 2.2 Granuloma A focal accumulation of epithelioid cells(macrophages altered in appearance to resemble epithelial cells) and multinucleated giant cells. This term is also applied to collections of lymphocytes surrounded by fibrous tissue 9.1.3. 3 Scar and Contraction
9.1.3 Acute Vs. Chronic Inflammation 9.1.3.1 Acute Inflammation Comprises cellular processes, soluble mediators, and vascular changes occurring immediately following injury to vascular tissue and is of relatively short duration (from a few minutes to a few days). The classical clinical signs are: heat, redness, swelling, and pain. In many cases function of the tissue is compromised. 9.1.3.2 Chronic Inflammation Cell types and activities associated with a persistent injury or permanent implant, that could continue for months or years. 9.1.3.2.1 Synovium The chronic inflammatory tissue bordering an implant often has the cell composition (macrophages and fibroblasts) and arrangement (cells in mono- or multiple-layer) consistent with synovium, The tissue that lines joints and encapsulates fluid-filled sacs (bursae). 9.1.3.2.2 Granuloma A focal accumulation of epithelioid cells (macrophages altered in appearance to resemble epithelial cells) and multinucleated giant cells. This term is also applied to collections of lymphocytes surrounded by fibrous tissue. 9.1.3.3 Scar and Contraction