Polydioxanones

Polydioxanone (PDS) is completely elirninated from the body upon absorption. The mechanism of polydioxanone degradation is similar to that observed for other synthetic bioabsorbable polymers. Polydioxanone degradation in vitro was affected by gamma irradiation dosage but not substantially by the presence of enzymes (39). The strength loss and absorption of braided PDS, but not monofilament PDS, implanted in infected wounds, however, was significantly greater than in noninfected wounds. 

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. 

Class III Premarket Approval. Similar to a new dmg approval, a premarket approval grants the appHcant a Hcense to market a specific weU-characterized device. These devices are subject to the requirements of Section 515 of the Eood, Dmg, and Cosmetic Act. A post-amendment device is a device put ia commercial distribution after May 28, 1976. If it is not substantially equivalent to a preamendment device it is automatically ia Class 111, and a premarket approval appHcation (PMA) is required. The appHcation must iaclude reports of preclinical and clinical studies done ia support of claims of safety and efficacy as well as any labeling claims made for the device. Once the PMA is submitted, the PDA determines whether the appHcation iacludes the required information. If the PMA is suitable for scientific review, the PDA has 180 days from the filing date to approve or deny the appHcation. Polybutester, polydioxanone, polyglyconate, and ePTPE sutures are all regulated as Class 111 devices. 

Polydimethylsiloxane oils, properties and applications of, 22 573-575, 576 Polydimethylsiloxane diol, in silanol condensation, 22 566 Polydimethylsiloxanes, 10 3 Polydioxanone, bioresorbable polymer,... 

Meanwhile Ethicon (and others) developed alternative absorbable surgical sutures, based, for example, on copolymers of polyglycolide with poly-L-lactide or poly(trimethylene carbonate), and on polydioxanone, and on poly(e-oxycaproate), and also on copolymers of these with polyglycolide or with each other. These different structures made it possible to provide fibres with different rates of absorption, with different degrees of stiffness or flexibility, and for use in monofilaments, braided multifilaments, and other yam structures, as required for different surgical operations. 

The aliphatic poly(ether lactonejs are a group of synthetic polymers with high elasticity and high tissue absorptivity [293]. The ether function in the polymer backbone adds flexibility to the ester chain. Ring-opening polymerization of l,4-dioxan-2-one yields an elastic polymer, polydioxanone, with a tensile strength similar to that of human tissue [294]. Polydioxanone has been successfully used to prepare monofilament sutures, with a flexibility superior to that of PGA sutures [294]. Recently, the lipase-catalyzed polymerization of polydioxanone was demonstrated [295]. 

Other types of synthetic biopolymers that have been in use for medical applications for a number of years are polyglycolide, polydioxanone and poly(lactide-co-glycolide). 

Most of the commercially available biodegradable devices are polyesters composed of homopolymers or copolymers of glycolide and lactide. There are also devices made from copolymers of trimethylene carbonate and e-caprolactone, and a suture product made from polydioxanone. 

Polydioxanone was the first clinically tested monofilament synthetic suture, known as PDS and marketed by Ethicon. 

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... 

Sell SA et al (2006) Electrospun polydioxanone-elastin blends potential for bioresorbable vascular grafts. Biomed Mater 1 (2) 72—80... 

McClure MJ et al (2009) Electrospinning-aligned and random polydioxanone-polycaprolactone-silk fibroin-blended scaffolds geometry for a vascular matrix. Biomed Mater 4(5) 055010... 

Indeed most polymers are receptive to attack including cellulose nitrate, cellulose acetate, polycaprolactone, polyethylene succinate, polyethylene adipate, polyvinyl alcohol, polybutadiene, styrene butadiene, butyl acrylonitrile, butadiene acrylonitrile, polyester polyurethanes, polyacetate, polyglycollate, polydioxanone and Nylon 2,6. 

Polydioxanone (PDS) was produced in the early 1980s as an absorbable suture material [33] ... 

Ray, J.A., et al, Polydioxanone (PDS), a novel monofilament synthetic absorbable suture. Surgery, Gynecology Obstetrics, 1981, 153, 497-507. 

Bartholomew, R. S., PDS (polydioxanone suture) a new S5mthetic absorbable suture in cataract surgery. A preliminary study, Ophthalmologica, 183, 81, 1981. 

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