Product Manual

60 days are nonabsorbable sutures. This terminology is somewhat misleading because
even some nonabsorbable sutures (i.e., silk, cotton and nylon) lose some tensile
strength during this 60-day interval. Postlethwait
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measured the tensile strength of
implanted nonabsorbable sutures during a period of two years. Silk lost approximately
50% of its tensile strength in one year and had no strength at the end of two years.
Cotton lost 50% of its strength in six months, but still had 30-40% of its original
strength at the end of two years. Nylon lost approximately 25% of its original strength
throughout the two-year observation period.
1. Nonabsorbable surgical sutures
The nonabsorbable sutures of Covidien (formerly Tyco Healthcare, Norwalk, CT)
can be classified according to their origin. Nonabsorbable sutures made from natural
fibers are silk sutures. Sofsilk™ silk sutures are nonabsorbable, sterile, non-mutagenic
surgical sutures composed of natural proteinaceous silk fibers called fibroin. This
protein is derived from the domesticated silkworm species Bombyx mori of the family
bombycidae. The silk fibers are treated to remove the naturally-occurring sericin
gum and braided sutures are available coated uniformly with a special wax mixture
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