Fibroblasts are recruited from surrounding intact tissue and begin to synthesize and deposit collagen. The process is amplified by both paracrine and autocrine cascades, and a temporary matrix of (weaker) type III collagen, fibronectin, and glycosamino-glycans is laid down in the wound. Phase III: Maturation and Remodeling (Week http://www.selleckchem.com/products/kpt-330.html 1�CYear 1) The third and final stage of wound healing is marked by the evolution of the matrix into a highly refined and ordered collagen complex. Inability to mature results in a weak and ineffective scar; overzealous refining results in keloid formation. Myofibroblasts begin to shrink and contract the wound to minimize the amount of collagen deposition that is required; the wound further contracts as collagen fibers crosslink to increase their strength.

Collagen deposition continues to occur over 4 to 6 weeks.1,2 Initially, the collagen is laid down in thin fibrils that run parallel to the wound��s surface. As the wound matures, the thin collagen fibers become progressively thicker and reorient themselves in such a fashion as to minimize stress. This is reflected as increasing tensile strength of the wound over the postoperative period. At 1 week the wound has 3% of its final strength, at 3 weeks it has 30% of its final strength, and at 3 months and beyond, it has approximately 80% of its final strength.2 Wounds will never regain the strength of uninjured tissues.

Effects of Foreign Bodies and Excess Inflammation on Wound Healing The presence of foreign bodies (ie, suture material) in wounds induces excessive inflammatory tissue responses that lower the body��s defense mechanism against infection, interfere with the proliferative phase of wound healing, and ultimately lead to inferior wound strength due to excessive scar tissue formation. Although normal wound healing from surgical trauma involves an inflammatory process, as briefly described above, these reactions typically subside within a week as phase I transitions into phase II. However, inflammatory tissue reactions due to the presence of suture material will persist as long as the foreign body remains within the tissue. The degree of tissue reaction in turn depends largely on the chemical nature and physical characteristics of the various suture materials. Classification and Characteristics of Suture Materials There are numerous ways to classify suture material.

One can look at natural versus synthetic fibers, coated versus uncoated, dyed versus undyed, or almost any property versus another property of the materials used. For the purposes of this review, we discuss 6 categories of suture classification that we believe best assist surgeons in choosing the proper suture Drug_discovery material for their surgeries. These are: Suture size Tensile strength Absorbable versus nonabsorbable Multifilament versus monofilament Stiffness and flexibility Smooth versus barbed Suture Size Sutures of all compositions are available in a variety of sizes.