Tissue Repair Chapter 3 Ms. Figueroa

Objectives Describe the steps in tissue repair Explain the difference in repair depending upon the type of tissue injured Define wound healing

Introduction (p. 100-101) The body has many defenses for protecting itself from pathogens and injuries: skin, cilia, and the acid in your stomach are just a few. When injury occurs, it stimulates an inflammatory and immune responses, which begins immediately. Inflammation- generalized body response to prevent further injury. Immune response- extremely specific to the body region and mounts a vigorous attack

Types of Wound Healing There are two main ways: regeneration and fibrosis Regeneration- replacement of destroyed tissue by the same kind of cells Fibrosis- repair done by dense fibrous connective tissue that results in scar tissue. Depends upon: a. Type of tissue damaged b. The severity of injury In general, clean cuts heal more successfully than ragged cuts

Stages of Wound Healing Inflammation Inflammatory chemicals make the capillaries permeable This allows clotting proteins and other substances from the bloodstream to flood the injured area. A clot forms, stopping blood loss and holding the edges of the wound together. The air dries the clot, hardens, and forms a scab

Granulation Granulation tissue forms (pink, delicate) Tissue contains phagocytes: dispose of the blood clot Connective tissue cells produce the building blocks of collagen fibers Permanently bridges the gap between the torn tissue

Regeneration Surface epithelium begins to regenerate It makes its way across the scab causing it fall off The new repaired area is referred to as a scar. A scar can be visible depending upon the deepness/severity of the original injury

Diabetic Wound Healing= Much Slower Process Normal healing process