Surgical sutures are made from a wide range of materials, from synthetic polymers like nylon and polypropylene to natural proteins like silk. The specific material a surgeon chooses depends on where in the body the suture is placed, how long the wound needs support, and whether the suture should dissolve on its own or stay permanently. Most modern sutures fall into two broad categories: absorbable (they break down inside the body over weeks to months) and non-absorbable (they remain intact indefinitely unless physically removed).
Absorbable vs. Non-Absorbable Materials
The single biggest distinction in suture materials is whether or not the body can break them down. Absorbable sutures lose most of their holding strength over a few weeks to several months, then dissolve completely through a chemical process called hydrolysis. They’re used for internal layers of tissue, deep closures, and areas where removing stitches later would be impractical or unnecessary. Organs that heal relatively quickly, like the stomach, colon, and bladder, are typically closed with absorbable materials.
Non-absorbable sutures stay in the body permanently or until a clinician takes them out. They’re the choice for tissues that heal slowly and need long-term support: tendons, ligaments, bone anchoring points, and the tough connective tissue layer called fascia. They’re also standard for blood vessel repairs and hernia closures, where lasting strength matters more than convenience.
Synthetic Absorbable Materials
The majority of absorbable sutures used today are synthetic polymers designed to lose strength on a predictable schedule. The three most common are built from different combinations of the same basic chemical building blocks (glycolide, lactide, caprolactone, and dioxanone), each tuned for a different absorption timeline.
- Poliglecaprone 25 (Monocryl): A single-strand suture made from a copolymer of glycolide and caprolactone. It loses strength quickly, retaining only about 30 to 40 percent of its original holding power after two weeks. The body fully absorbs it within 90 to 120 days. It’s commonly used for skin closures and soft tissue layers that don’t need prolonged support.
- Polyglactin 910 (Vicryl): A braided suture made from 90 percent glycolide and 10 percent lactide. It holds up longer than Monocryl, keeping 50 to 65 percent of its strength at two weeks. By three weeks, though, almost no holding strength remains. Total absorption takes 60 to 90 days. It’s one of the most widely used absorbable sutures for internal tissue layers.
- Polydioxanone (PDS): A single-strand suture that retains strength far longer than the other two. It still has 74 percent of its original strength at two weeks, 50 percent at four weeks, and 25 percent at six weeks. Complete absorption doesn’t happen until six to seven months after placement. This makes it well suited for tissues that need extended support during healing.
The tradeoff between these materials is straightforward: faster absorption means less time holding the wound together, while slower absorption provides longer support but means the foreign material stays in the body longer.
Non-Absorbable Synthetic Materials
When a wound needs permanent or very long-term support, surgeons turn to synthetic materials that the body cannot break down. The most common options are nylon, polypropylene, polyester, and polybutester. Each comes as either a single strand (monofilament) or multiple strands woven together (braided), and that structure affects how the suture handles and how tissue responds to it.
Nylon sutures are available in both monofilament and braided forms. They’re widely used for skin closures and general soft tissue repair. Polypropylene sutures are monofilament, extremely smooth, and provoke very little tissue reaction, which makes them popular for vascular surgery and any situation where minimal scarring is important. Polyester sutures are braided, giving them excellent knot security, and they’re frequently used in cardiovascular and general surgery. Polybutester is a less common monofilament option with some built-in elasticity, allowing it to stretch slightly with tissue swelling and then return to its original length.
Stainless steel wire is also used as a suture material, particularly for closing the breastbone (sternum) after open-heart surgery or for repairing tendons and bones. It’s the strongest suture material available but is rigid and difficult to handle, so its use is limited to situations where maximum strength is essential.
Natural Suture Materials
Before synthetic polymers took over, natural materials were the only option. Two natural suture materials are still in use today: silk and catgut.
Silk sutures come from the fibers produced by silkworms. They handle beautifully, tie easily, and hold knots well, which is why some surgeons still prefer them despite better synthetic alternatives. The downside is that silk triggers more inflammation than almost any other suture material. In comparative studies, silk consistently produces the strongest inflammatory response, significantly more than synthetic monofilament materials and even more than catgut.
Catgut (sometimes called “plain gut” or “chromic gut”) is made from the intestinal lining of sheep or cattle, not cats. It’s a natural absorbable material that the body breaks down through enzyme activity rather than the hydrolysis process that dissolves synthetic absorbable sutures. “Chromic” catgut is treated with chromium salts to slow its absorption and extend its useful life in the body. Catgut has largely been replaced by synthetic absorbable sutures, which offer more predictable strength and absorption timelines, but it’s still available and used in some settings.
Monofilament vs. Braided Construction
The material itself is only half the story. How that material is physically constructed changes its behavior significantly. Monofilament sutures are a single smooth strand. Braided sutures are made of many smaller fibers woven together, similar to a rope.
Braided sutures are easier to handle and hold knots more securely because the textured surface creates friction. But that same texture has a significant drawback: the tiny spaces between the woven fibers can harbor bacteria. This “wicking” effect can draw microorganisms along the suture and into the wound, increasing infection risk. Monofilament sutures resist bacterial colonization because their smooth surface offers nowhere for bacteria to hide. They also slide through tissue with less drag, causing less trauma. The tradeoff is that monofilament sutures are stiffer and require more throws (wraps) per knot to stay tied.
Polypropylene, polydioxanone, poliglecaprone 25, and nylon are all available as monofilaments. Polyglactin 910, polyester, and silk are typically braided.
How Tissue Reacts to Different Materials
Every suture triggers some degree of inflammation when placed in tissue. The body recognizes it as foreign and mounts a response. But the intensity of that reaction varies dramatically depending on the material. In general, synthetic monofilament sutures cause the least inflammation, while natural braided materials like silk cause the most.
In animal studies directly comparing tissue reactions, synthetic monofilament materials (like polyvinylidene fluoride) produced the mildest inflammation at seven days, while silk sutures produced significantly more. Braided synthetic sutures made from polyglycolic acid fell somewhere in the middle. This is one reason why monofilament synthetics have become the default choice for most surgical closures, particularly in cosmetic procedures or areas prone to infection, where excessive inflammation would worsen outcomes.
Antimicrobial Coatings
Some modern sutures are coated with an antiseptic called triclosan to reduce the risk of surgical site infections. Triclosan is a broad-spectrum antimicrobial compound that’s been incorporated into several major suture brands (marketed with a “Plus” designation, such as Vicryl Plus or Monocryl Plus). The coating works by reducing bacterial colonization on the suture surface, which is important because bacteria clinging to suture material can serve as a starting point for wound infections.
Multiple studies have confirmed that triclosan-coated sutures reduce both bacterial colonization and surgical site infection rates. The coating doesn’t appear to generate antibiotic resistance, and in most studies it doesn’t interfere with normal wound healing or change how the suture absorbs. One small pilot study in breast reduction surgery did find higher rates of wound separation with triclosan-coated sutures, but this finding has not been replicated broadly.
Barbed Sutures
A newer category of suture doesn’t introduce a new material so much as a new design. Barbed sutures have tiny projections cut into the filament that grip tissue as they pass through, eliminating the need for knots. The barbs collapse flat when the suture is pulled in one direction but lock into place when pulled the other way, anchoring the suture along its entire length rather than just at the knot points.
These sutures are made from the same polymers used in conventional sutures. Absorbable barbed versions use polydioxanone or glycolide-caprolactone copolymers. Non-absorbable barbed versions use polypropylene. Brand names like Quill and V-Loc are common in minimally invasive and laparoscopic procedures, where tying knots through small incisions is technically difficult. The knotless design also distributes tension more evenly along the wound, which can improve closure in some surgical settings.
Why the Material Matters for Your Surgery
The choice of suture material directly affects how your wound heals. A tissue that heals slowly, like a tendon or fascia, needs a suture that holds its strength for weeks or months. A quickly healing organ like the bladder only needs a few weeks of support, so a fast-absorbing suture makes more sense and avoids leaving unnecessary foreign material behind. Skin closures are often done with non-absorbable nylon or polypropylene that gets removed at a follow-up visit, or with a fast-absorbing material like poliglecaprone 25 that dissolves before it needs to be taken out.
Infection risk also plays into the decision. In contaminated or high-risk wounds, monofilament sutures are preferred over braided ones because they resist bacterial colonization. Adding a triclosan coating provides an extra layer of protection. In clean, low-tension wounds, the surgeon has more flexibility and may choose based on handling characteristics or personal preference.