Polyglycohc acid

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. 

Polylactic Acid. Polylactic acid (PLA) was introduced in 1966 for degradable surgical implants. Hydrolysis yields lactic acid, a normal intermediate of carbohydrate metaboHsm (23). PolyglycoHc acid sutures have a predictable degradation rate which coincides with the healing sequence of natural tissues. 

PolyglycoHc Acid. PolyglycoHc acid (PGA), also known as polyglycoHde, was first reported in 1893, but it wasn t until 1967 that the first commercially successful patent was granted for sutures (27). Like polylactide, polyglycoHde is synthesized from the cycHc diester as shown below ... 

Low humidity ethylene oxide gas sterilisa tion procedures and moisture-proof packaging for polyglycoHc acid products are necessary because of the susceptibihty to degradation resulting from exposure to moisture and gamma sterilisation. 

Similar to pure polyglycoHc acid and pure polylactic acid, the 90 10 glycolide lactide copolymer is also weakened by gamma irradiation. The normal in vivo absorption time of about 70 days for fibrous material can be decreased to less than about 28 days by simple exposure to gamma radiation in excess of 50 kGy (5 Mrads) (35). 

Chu, C.C. and Browning, A., 1988. The study of thermal and gross morphologic properties of polyglycohc acid upon annealing and degradation treatments. J. Biomed. Mater. Res., 22 699-712. 

Chu, C.C. and Louie, M., 1985. A chemical means to study the degradation phenomena of polyglycohc acid absorbable polymer. J. Appl. Polym. Sci., 30 3133-3141. 

PolyglycoHc acid (PGA) A synthetic polymer formed from glycolic acid monomers which degrades by hydrolysis. 

The holding power of the pin comes from elastic deformation of surrounding bone. In order to increase the holding power to bone, threaded pins are used. Most pins are made of 316L stainless steel however, recently, biodegradable pins made of polylactic or polyglycoHc acid have been employed for the treatment of minimally loaded fractures. 

Wang C, Cen L, Yin S, Liu Q, Liu W, Cao Y, et al. A small diameter elastic blood vessel wall prepared under pulsatile conditions from polyglycohc acid mesh and smooth muscle cells differentiated from adipose-derived stem cells. Biomaterials February 2010 31(4) 621-30. 

Postlethwait RW. Polyglycohc acid surgical suture. Arch Surg 1970 101 489-94. 

Higgins, S. P., A. K. Solan, and L. E. Niklason (2003). Effects of polyglycohc acid on porcine smooth muscle cell growth and differentiation. Journal of Biomedical Materials Research Part A 67A(l) 295-302. 

Barralet, J.E., Wallace, h.h., and Strain, A.J., Tissue engineering of human biliary epithelial cells on polyglycoHc acid/polycaprolactone scaffolds maintains long-term phenotypic stability. Tissue Eng. 2003,9(5), 1037-1045. 

Mooney, D.J., Mazzoni, C.L., Breuer, K., McNamara, l.R, Vacant , l.R, and Langer, R., 1996b. Stabilized polyglycohc acid fibre-based tubes for tissue engineering. Biomaterials, 17 115 124. 

Pratt, L. and Chu, C.C., 1993b. Hydrolytic degradation of a-substituted polyglycohc acid a semi-empirical computational study. /. Comput. Chem., 14 809-817. 

Mahmoudifar, N. and RM. Doran, Chondrogenic differentiation of human adipose-derived stem cells in polyglycohc acid mesh scaffolds under dynamic culture conditions. Biomaterials, 2010. 31(14) 3858-67. 

Ueki, K., Takazakura, D., Marukawa, K. et al. 2003. The use of polylactic acid/polyglycohc acid copolymer and gelatin sponge complex containing human recombinant bone morphogenetic protein-2 foUow-ing condylectomy in rabbits. / Craniomaxillofac Surg 31(2).T 07-14. 

Jiao, H, Yao, J, Yang, Y et al. 2009. Chitosan/polyglycohc acid nerve grafts for axon regeneration from prolonged axotomized neurons to chronically denervated segments. Biomaterials 30(28) 5004-5018. 

Bucknall TE, Elhs H. Abdominal wound closure comparison of monofilament nylon and polyglycohc acid. Surgery 1981 6 672-7. 

Yokoya,S., Mochizuki, Y.,Nagata, Y.,Deie, M., and Ochi, M. 2008. Tendon-bone insertion repair and r en-eration using polyglycohc acid sheet in the rabbit rotator cuff injury model. Am. J. Sports Med. 36 1298-1309. 

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