Suture Materials Comparison

The choice of suture material determines the mechanical performance, tissue interaction, and clinical outcome of a wound closure. Each material has a unique combination of tensile strength, flexibility, surface friction, tissue reactivity, and (for absorbable materials) degradation rate. Understanding these properties at the material level is essential for informed suture selection.

This guide covers the seven primary suture material categories, with specific reference to Desmo Care's product range. All specifications are typical values under standard USP/EP test conditions.

PGA (Polyglycolic Acid)

Polyglycolic acid is a linear aliphatic polyester first introduced as a surgical suture material in the 1970s. It was the first synthetic absorbable suture and remains the most widely used absorbable material globally. PGA is synthesized by ring-opening polymerization of glycolide, producing a highly crystalline polymer (approximately 46-52% crystallinity) with excellent initial tensile strength.

PGA degrades by hydrolysis of its ester bonds. The high crystallinity results in relatively rapid degradation compared to other synthetic absorbable polymers. Standard PGA sutures (DesmoNex) retain 75% of tensile strength at 2 weeks and 40% at 3 weeks, with complete absorption in 60-90 days. The high-strength variant (Absorbex) with Glycomer 370 coating retains 70% at 2 weeks and 50% at 3 weeks.

The rapid-absorbing formulation (DesmoNex Rapid) is gamma-irradiated to reduce molecular weight, accelerating absorption to 42 days with tissue support limited to 7-10 days and 50% strength retention at 5 days.

PGA sutures are manufactured as braided multifilaments and coated to reduce surface friction. DesmoNex uses a polycaprolactone and calcium stearate coating that provides smooth tissue passage while minimizing capillarity. Clinical applications include general soft tissue approximation, fascial closure, peritoneal closure, pediatric surgery, plastic surgery, ophthalmic procedures, and oral surgery.

PDO (Polydioxanone)

Polydioxanone is a polyester synthesized by ring-opening polymerization of p-dioxanone. Its ether-ester backbone gives it greater flexibility and lower crystallinity (approximately 37-55%) compared to PGA, which translates to a longer degradation timeline and extended strength retention.

DesmoPol retains 70% of tensile strength at 2 weeks and 50% at 6 weeks — significantly longer than PGA. Complete absorption occurs at 180-210 days. This makes PDO the material of choice when extended tissue support is needed but permanent fixation is not required.

As a monofilament, PDO suture passes through tissue with minimal drag and does not harbor bacteria in interstices. It produces less tissue reaction than braided absorbable sutures. However, PDO monofilament has moderate “memory” — it tends to retain the coil shape from packaging, which can affect handling. Surgeons typically find that gentle straightening before use addresses this.

Primary applications include pediatric cardiovascular surgery (where growth accommodation is needed), orthopedic soft tissue closure, fascial closure requiring extended support, plastic and reconstructive surgery (subcuticular closure), and general soft tissue approximation where monofilament properties and extended strength retention are desired.

PGCL (Polyglyconate)

Polyglyconate (PGCL) is a copolymer of glycolic acid and trimethylene carbonate. This copolymer composition gives PGCL a balance between the high strength of glycolide-based polymers and the flexibility of carbonate-based polymers, resulting in a monofilament suture with excellent handling characteristics.

DesmoCryl retains 65% of tensile strength at 2 weeks and 40% at 3 weeks, providing medium-term tissue support of 21-28 days. Complete absorption occurs at 180-210 days — similar to PDO. The standard version is suited for general soft tissue approximation, pediatric procedures, plastic surgery, and ophthalmic procedures.

The rapid version (DesmoCryl Rapid) provides shorter tissue support of 7-10 days, making it ideal for superficial closure where suture removal should be avoided.

PGCL monofilament offers particularly smooth tissue passage — smoother than PDO in many surgeons' experience — combined with excellent knot security for a monofilament material. This makes it a preferred choice in plastic surgery and pediatrics where both atraumatic tissue passage and reliable knot performance are required.

PLLA-PCL (Poly-L-Lactide-co-Caprolactone)

PLLA-PCL is a copolymer of poly(L-lactide) and poly(epsilon-caprolactone). The combination of the slowly degrading PLLA component with the flexible PCL component produces a suture with exceptionally long strength retention — the longest of any absorbable suture material currently available.

DesmoCapro retains approximately 80% of its original tensile strength at 90 days post-implantation — three times longer than PDO maintains comparable strength. Tissue support extends up to 180 days. Mass loss is minimal until 90 days, with essentially complete absorption between 12-18 months.

This profile positions PLLA-PCL as the absorbable alternative for applications traditionally requiring non-absorbable sutures. In cardiovascular, orthopedic, and reconstructive surgery where tissue healing is slow and prolonged mechanical support is essential, DesmoCapro provides the extended support duration of non-absorbable materials with the eventual absorption of absorbable materials.

The monofilament structure ensures minimal tissue reaction and resistance to bacterial colonization. The material produces less inflammatory response than PGA braided sutures, making it suitable for procedures where tissue quality and healing environment are critical priorities.

Polypropylene

Polypropylene is a stereo-regular crystalline polyolefin. It is one of the most chemically inert suture materials available — it does not hydrolyze, is resistant to enzymatic degradation, and provokes minimal inflammatory tissue reaction. Its monofilament structure further reduces tissue interaction and bacterial adherence.

DesmoMid maintains its tensile strength permanently in tissue with no degradation over time. This combination of permanent strength, chemical inertness, and monofilament construction makes polypropylene the standard suture material for cardiovascular surgery, where the suture must withstand constant hemodynamic stress while minimizing thrombogenicity at the anastomotic site.

Polypropylene is also used in general soft tissue closure, hernia repair (mesh fixation), and plastic surgery. Its smooth monofilament surface allows easy removal when used for percutaneous skin closure — the suture slides out cleanly without tissue adherence.

The primary handling consideration is that polypropylene has moderate memory and requires careful knot technique. Additional throws (typically 5-6 per knot) are recommended to ensure knot security, as the smooth surface can allow knot slippage if inadequately secured.

Silk (Natural Protein Fiber)

Silk is a natural protein fiber produced by the Bombyx mori silkworm. It is classified as non-absorbable, though it gradually loses tensile strength over 6-12 months in tissue and may eventually be fully degraded by proteolytic enzymes over 1-2 years. Clinically, it is treated as non-absorbable because it is not reliably eliminated and typically requires removal in external applications.

DesmoSilk is widely regarded as the gold standard for suture handling. Its braided construction provides exceptional pliability, precise knot placement, and high knot security — silk holds knots more reliably than any other suture material with fewer throws required. These handling properties make it the preferred suture for procedures demanding fine motor control, particularly ophthalmic and microsurgical applications.

The trade-off is tissue reactivity. Silk provokes a greater inflammatory response than synthetic materials, which can lead to encapsulation of the suture by granulation tissue. This makes silk less suitable for permanent implantation in deep tissue and inappropriate for use in contaminated or infected wounds where the braided structure could harbor bacteria.

Clinical applications include general surgery (ligatures, wound closure), ophthalmic surgery (tarsorrhaphy, strabismus), oral surgery, and any application where the suture will be removed after initial healing and where handling precision outweighs concerns about tissue reactivity.

Linen (Natural Plant Fiber)

Linen sutures are derived from flax (Linum usitatissimum) plant fibers. They are manufactured as twisted multifilament strands that provide high initial tensile strength and excellent knot security. Unlike braided sutures, the twisted construction of linen gives it a distinct handling feel that many gastrointestinal surgeons prefer.

DesmoLen maintains its non-absorbable classification, providing permanent tissue support. The material produces minimal tissue reaction relative to other natural fibers and offers reliable performance in the gastrointestinal environment.

Primary applications include gastrointestinal procedures, general surgery, and oral surgery. While synthetic alternatives have displaced linen in many applications, it retains a clinical niche where its specific combination of natural biocompatibility, knot security, and handling characteristics is valued.

Stainless Steel (316L Surgical Grade)

Surgical-grade 316L stainless steel is an austenitic chromium-nickel-molybdenum alloy. The “L” designation indicates low carbon content (below 0.03%), which improves corrosion resistance — particularly resistance to intergranular corrosion in the chloride-rich environment of body tissues.

DesmoSter provides the highest tensile strength of any suture material, with permanent strength retention and essentially zero tissue reactivity. The material produces no inflammatory response and is completely resistant to degradation in tissue. It is available in a wide USP range (5/0 to 7), with the larger gauges used in sternal closure and the finer gauges in orthopedic applications.

Sternal closure after median sternotomy remains the primary application. No polymer suture can match the tensile strength required to secure the sternum under the cyclic loading of respiration. Steel sutures are also used in abdominal wall closure in high-risk patients (where burst abdomen risk is elevated) and in orthopedic tendon repair requiring maximum fixation strength.

The primary limitation is handling. Steel sutures require dedicated wire-handling instruments, can kink if mishandled (kinking creates a stress concentration that weakens the wire), and cut ends must be carefully buried to prevent tissue irritation. DesmoSter is sterilized by gamma irradiation rather than ethylene oxide, as metals do not require gas-permeable packaging.

Complete Materials Comparison Table

Frequently Asked Questions