Suture synthetic

Absorbable sutures are classified by the USP into coUagen and synthetic sutures. Synthetic absorbable sutures are available as braids or monofilaments. Absorbable sutures are only intended for indications where temporary wound support is needed. 

Clothing made from this fabric is used to protect firefighters because of its fire resistance. Because it also insulates, Gore-Tex clothing is used by military forces and by many amateur athletes, for protection during strenuous activity in the cold. In addition to its use in protective clothing, Gore-Tex has been used in millions of medical procedures for sutures, synthetic blood vessels, and tissue reconstruction. 

Egyptians sutured wounds as early as 3500 b.c. using a variety of natural polymers including treated intestines, which are the early versions of collagen-based surgical gut sutures. Synthetic, absorbable polyesters based on... 

Natural collagen-based absorbable sutures have largely been replaced by synthetic absorbable sutures. Synthetic absorbable sutures are made from aliphatic absorbable polyesters and contain one or more of the five basic building blocks glycolide,L-lactide,p-dioxanone, -caprolactone and trimethylene carbonate. With the exception of the trimethylene carbonate building block which results in amorphous polymers, the polymers from the other four blocks are semicrystaUine. 

The first synthetic polyglycoHc acid suture was introduced in 1970 with great success (21). This is because synthetic polymers are preferable to natural polymers since greater control over uniformity and mechanical properties are obtainable. The foreign body response to synthetic polymer absorption generally is quite predictable whereas catgut absorption is variable and usually produces a more intense inflammatory reaction (22). This greater tissue compatibihty is cmcial when the implant must serve as an inert, mechanical device prior to bioresorption. 

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 sold ia the United States under generic and/or proprietary names. The most widely sold sutures are Hsted ia Table 1. The generic names for the synthetic polymeric sutures are those that have been approved by the United States Adopted Names Council (USAN). 

Braided Synthetic Absorbable Sutures. Suture manufacturers have searched for many years to find a synthetic alternative to surgical gut. The first successful attempt to make a synthetic absorbable suture was the invention of polylactic acid [26023-30-3] suture (15). The polymer was made by the ring-opening polymerization of L-lactide [95-96-5] (1), the cycUc dimer of L-lactic acid. 

Monofilament Synthetic Absorbable Sutures. Ethicon iatroduced the first monofilament synthetic absorbable suture ia 1984 when it marketed PDS polydioxanone (4) sutures. The polymer is produced by the bulk polymerisation of 2,5- -dioxanone. The suture is distributed under the trade name PDS 11. It is claimed to retain approximately 50% of its strength four weeks after implantation, 25% at six weeks, and to be absorbed within six months. 

Although silk and cotton are classified as nonabsorbable sutures, these do lose strength gradually in living tissue and slowly break up after long periods of implantation (18). The USP specifications for Class I nonabsorbable sutures (silk or synthetic fibers) are shown in Table 4. 

Braided Synthetic Nonabsorbable Sutures. Braided synthetic nonabsorbable sutures are made by melt-spinning thermoplastic polymers into fine filaments (yams), and braiding them, with or without a core, to form multifilament sutures in a range of sizes. Nylon-6,6 [32131 -17-2] (7) is a polyamide produced by the condensation polymerization of adipic acid and 1,6-hexanediamine. 

Monofilament Synthetic Nonabsorbable Sutures. Monofilament synthetic nonabsorbable sutures are made from thermoplastic resins melt-spun to form monofilaments. Spinnarets of different capillary diameter are used to make a range of suture sizes. 

Polymers used in medicine fall into two main categories those that are sufficiently inert to fulfill a long-term structural function as biomaterials or membranes, and those that are sufficiently hydrolytically unstable to function as bioeradible materials, either in the form of sutures or as absorbable matrices for the controlled release of drugs. For the synthetic organic polymers widely used in biomedicine this often translates to a distinction between polymers that have a completely hydrocarbon backbone and those that have sites in the backbone that are hydrolytically sensitive. Ester, anhydride, amide, or urethane linkages in the backbone usually serve this function. 

Common biodegradable polymers for medical devices are constructed from synthetic linear aliphatic polyesters. One material commonly used for internal sutures is poly(glycolic acid) (PGA). PGA is synthesized from the dimer of glycolic acid (Fig. 13.1.l). 1... 

Synthetic blood vessels and patches for soft tissue regeneration surgical sutures for use in vascular, cardiac, general surgery and orthopaedic procedures. .. 

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