Suture, artificial

This approach was considered because it would permit the synthesis of biomaterials (for drug delivery systems, sutures, artificial organs, etc.) which are derived from nontoxic metabolites (amino acids and dipeptides) while also having other desirable properties for example, the incorporation of an anhydride linkage into the polymer backbone could result in rapid biodegradability, an iminocarbonate bond may provide mechanical strength, and an ester bond may result in better film and fiber formation. 

Polyethylene terephthalate Sutures, artificial vascular grafts... 

Collagen has been widely studied for biomedical applications such as bioresorbable sutures, artificial skin, wound dressings, and vascular grafts, due to its biocompatibility, mechanical properties, and degradability by enzymes like... 

These include use of chitosan in tissue engineering, in the preparation of sutures, artificial skin and soft/hard contact lens, owing to its excellent film-forming ability [170],... 

Personal care Hair care Dietary foods Skin care Bum therapy Biodegradable suture Artificial skin... 

Health Safety. PET fibers pose no health risk to humans or animals. Eibers have been used extensively iu textiles with no adverse physiological effects from prolonged skin contact. PET has been approved by the U.S. Eood and Dmg Administration for food packagiug and botties. PET is considered biologically iuert and has been widely used iu medical iaserts such as vascular implants and artificial blood vessels, artificial bone, and eye sutures (19). Other polyester homopolymers including polylactide and polyglycoHde are used iu resorbable sutures (19,47). 

In contrast, the total artificial heart (TAH) is designed to overtake the function of the diseased natural heart. While the patient is on heart—lung bypass, the natural ventricles are surgically removed. Polyurethane cuffs are then sutured to the remaining atha and to two other blood vessels that connect with the heart. 

Polymers are a fundamental part of the modem world, showing up in everything from coffee cups to cars to clothing. In medicine, too, their importance is growing for purposes as diverse as cardiac pacemakers, artificial heart valves, and biodegradable sutures. 

Teflon was introduced to the public in 1960 when the first Teflon-coated muffin pans and frying pans were sold. Like many new materials, problems were encountered. Bonding to the surfaces was uncertain at first. Eventually the bonding problem was solved. Teflon is now used for many other applications including acting as a biomedical material in artificial corneas, substitute bones for nose, skull, hip, nose, and knees ear parts, heart valves, tendons, sutures, dentures, and artificial tracheas. It has also been used in the nose cones and heat shield for space vehicles and for their fuel tanks. 

Long-term inertness without loss of strength, flexibility, or other necessary physical property is needed for use in artificial organs, prostheses, skeletal joints, etc. Bioerodability is needed when the polymer is used as a carrier such as in controlled release of drugs, removal of unwanted materials, or where the materials purpose is short-lived, such as in their use as sutures and frames for natural growth. 

Last but not least requirement, artificial arterial substitutes must be able to be connected to the host s vessels using sutures, the only reliable mean surgeons trust (Fig. 2). The connections performed must be stable and blood tight for as long as the prosthesis will remain patent. This last condition has supported the interest of surgeons for vascular prostheses made of woven or non-woven and knitted synthetic fabrics. The following sections give an outline of the different steps that line the evolution of materials for the cardiovascular system, and present some prospective solutions that have been proposed and supposed to improve the performances of these materials. 

Materials synthesis is a necessary component in the development of advanced technologies for national security and homeland defense. For instance, new composites, nanoscale molecules and compounds, and polymers are needed for tougher, explosion- or puncture-resistant materials that can be employed in buildings, garments, bridges, and other products and structures. Personal protective materials could be enhanced with new chemical adsorbents filter materials, impermeable membranes, artificial sutures, and improved energetic materials for... 

Artificial Soft Biologies. In addition to sutures, polymers are used for a number of biomedical applications, as illustrated in Figure 5.128. Polymers used for hard structural applications such as dentures and bones are presented in this figure, but will be described in the next section. In this section, we will concentrate on polymers for soft biological material applications and will limit the description to mechanical properties as much as possible. 

Artificial biologies, whelher soff or hard, can be categorized as eifher temporary (short term) or permanent (long term) in their intended application. Most, but certainly not all, polymers for biomedical applications are of the short-term type and include sutures, drug delivery devices, temporary vascular grafts and stents, tissue scaffolds. 

Our investigations on BASYC (BActerial-SYnthesized Cellulose) as artificial blood vessel and cuff for nerve suturing [65] are reviewed below. Because of... 

Most of the studies on PLA degradation have concentrated on abiotic hydrolysis [35-37]. The effects of, e.g., residual monomer and other impurities, molecular weight and copolymerization on hydrolysis rate and properties have been studied [3,37-42]. Impurities, residual monomer [43,44], and peroxide modification [45] all increase the hydrolysis rate, while copolymerization can either increase (GA-copolymers) or decrease (CL, DXO-copolymers) the hydrolysis rate. Degradation of PLA and its copolymers in clinical applications ranging from absorbable sutures to drug delivery systems and artificial ligaments has also been widely studied [46-48]. 

For much of the last century, scientists attempted to make useful plastics from hydroxy adds such as glycolic and lactic acids. Poly(glycolic acid) was first prepared in 1954, but was not commercially developed because of its poor thermal stability and ease of hydrolysis. It did not seem like a useful polymer. Approximately 20 years later it found use in medicine as the first synthetic suture material, useful because of its tendency to undergo hydrolysis. After the suture has served its function, the polymer biodegrades and the products are assimilated (Li and Vert 1995). Since then, suture materials, prosthetics, artificial skin, dental implants, and other surgical devices made from polymers and copolymers of hydroxy carboxylic acids have been commercialized (Edlund and Albertsson 2002). 

Nonetheless, artificial biodegradable aliphatic polyesters are still mainly based on the industrial polymerization of monomers such as glycolic acid (PGA), lactic acid (PLA), and caprolactone (PCL). (See Figure 12.29). These polyesters are applied in implants, absorbable sutures, controlled-release packaging, and degradable films and moldings. 

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