Absorbable sutures nonabsorbable

Surgical sutures are sterile, flexible strands used to close wounds or to tie off tubular structures such as blood vessels. Made of natural or synthetic fiber and usually attached to a needle, they are available ia monofilament or multifilament forms. Sutures are classified by the United States Pharmacopeia (USP) (1) as either absorbable or nonabsorbable. The USP also categorizes sutures according to size (diameter) and Hsts certain performance requirements. Sutures are regulated by the Food and Dmg Administration (FDA) as medical devices under the Food, Dmg, and Cosmetics (FDC) Act of 1938, the Medical Device Act of 1976, and the Medical Device Reporting regulation of 1995. 

Sutures are required to hold tissues together until the tissues can heal adequately to support the tensions exerted on the wound duting normal activity. Sutures can be used ia skin, muscle, fat, organs, and vessels. Nonabsorbable sutures are designed to remain ia the body for the life of the patient, and are iadicated where permanent wound support is required. Absorbable sutures are designed to lose strength gradually over time by chemical reactions such as hydrolysis. These sutures are ultimately converted to soluble components that are then metabolized and excreted ia urine or feces, or as carbon dioxide ia expired air. Absorbable sutures are iadicated only where temporary wound support is needed. 

With the exception of sutures made from steel, all others are polymeric. Sutures are generally divided into two broad categories (1) absorbable sutures, which are absorbed by the healing tissue through proteolysis or hydrolysis and (2) nonabsorbable sutures, which remain in the tissue, often for the lifetime of the patient. 

In general, absorbent sutures are composed of materials that are natural to mammals, such as catgut, and to materials that are either quite susceptible to hydrolysis and/or polymers derived from natural materials such as polyglactin, which is a copolymer of lactic and glycolic acid. Nonabsorbent sutures can be made from natural materials such as cotton, which is a plant material, polymers that range from being hydrophobic to hydrophilic, and steel. 

Fiber characteristics that should be taken into account for making filters include temperature capability, corrosion resistance (withstand adds, alkalies, solvents, etc.), hydrolysis (humidity levels), dimensional stability, and cost. Among important medical application of fibers, we should mention sutures and filters. Sutures are used to close the wound during surgical operations. Fibers used as sutures can be absorbable or nonabsorbable. The main requirements are that the suture must have only a minimal amount of reaction with the tissue and, in the case of absorption, there must be minimal chemical irritation (Lyman,... 

Absorbable sutures are collagen sutures, polyglycolic acid and its lactide copolymers, and polydioxanone. Nonabsorbable sutures include silk, cotton, polyethylene, polypropylene, nylon, PET, and stainless steel. These fibers can be used as monofilaments or multifilaments (twisted or braided). Figure 2.16 shows examples of filters for medical purposes made of polyester, nylon, and metallic fibers. In summary, fibers are used in almost everything that we can see in our... 

Sutures remain the most common method of tpproximating the divided edges of tissue (1). Sutures are categorised by size, material, design and behaviour. Absorbable and nonabsorbable materials are further divided into synthetic versus natural products, some of vdiich can be fabricated in braided and/or monofilament form. Non-absorbable sutures have played an important role in the development of surgical procedures, generally made of silk, polyamide, polyester, polypropylene, polyethylene and poly(tetrafluoroethylene) (2). 

The previous chapter provided a general overview of the properties of materials used for surgical sutures and of the desirable characteristics of such materials. This chapter considers absorbable and nonabsorbable materials in greater detail, looking within each category first at natural materials, and second at synthetic materials. In the section on absorbable materials, natural materials reviewed are ... 

Materials for absorbable and nonabsorbable surgical sutures 279 Table 11.1 Building blocks of commercial synthetic absorbable sutures... 

Casey, D J and Lewis O G (1986), Absorbable and nonabsorbable sutures , in von Recum A F, Handbook of Biomaterials Evaluation Scientific, Technical, and Clinical Testing of Implant Materials, New York, Macmillan Publishing, 86-94. 

Abstract The chapter describes properties of materials used for sutures that may be absorbable or nonabsorbable of varying size made from monofilament, multifilament, twisted or braided threads. 

Based on the US Pharmacopeia, absorbable and nonabsorbable sutures are defined as follows ... 

---