what are dissolvable stitches made of

2 min read 19-03-2025

Dissolvable stitches, also known as absorbable sutures, are a crucial advancement in surgical techniques. Unlike traditional stitches that require removal, these sutures gradually break down and dissolve within the body. But what are they actually made of? This article will explore the materials used to create these remarkable medical tools and discuss their properties.

The Materials of Dissolvable Stitches

Dissolvable stitches are primarily composed of materials that the body can naturally absorb and metabolize. The most common materials include:

1. Polyglycolic Acid (PGA) and Polylactic Acid (PLA)

These synthetic polymers are the workhorses of the dissolvable stitch world. PGA and PLA are both biodegradable, meaning they break down into simpler substances over time. These simpler substances are then absorbed into the body and eliminated naturally. Stitches made from these materials are often used for internal tissues where removal is difficult or impractical.

PGA: Offers good tensile strength initially, but loses it more rapidly than PLA.
Polydioxanone (PDO): A longer lasting synthetic absorbable suture. It provides stronger tensile strength and is absorbed more slowly.

2. Polydioxanone (PDO)

PDO is another synthetic polymer frequently used in creating dissolvable stitches. It offers superior strength and a slower absorption rate compared to PGA and PLA, making it suitable for situations requiring longer-lasting support.

3. Vicryl (Polyglactin 910)

Vicryl is a popular copolymer composed of glycolide and lactide. This combination provides excellent strength and a controlled absorption rate, striking a balance between early support and timely dissolution. It's frequently used for subcutaneous tissue and skin closure.

4. Catgut

Catgut is a naturally derived absorbable suture made from collagen extracted from the intestines of sheep or cows. Although historically significant, its use has decreased due to concerns about allergic reactions and inconsistent absorption rates. It is still used in certain applications but is gradually being replaced by synthetic alternatives.

How Dissolvable Stitches Dissolve

The process of dissolving varies depending on the specific material used. However, the general principle is enzymatic hydrolysis. The body's enzymes break down the polymer chains of the suture material into smaller molecules that are then absorbed into the bloodstream and ultimately eliminated by the kidneys or liver. This process happens gradually over several weeks or months, depending on the type of suture and the location of the stitch.

Factors Influencing Absorption Rate

Several factors influence how quickly a dissolvable stitch will dissolve. These include:

The material itself: Different materials have inherently different absorption rates.
The size of the suture: Thicker sutures generally take longer to dissolve than thinner ones.
The location of the suture: Stitches in areas with higher blood flow tend to dissolve faster than those in areas with lower blood flow.
The patient's overall health: Factors such as age and immune function can also affect absorption rates.

Conclusion

Dissolvable stitches represent a significant advancement in surgical technology. Their composition, primarily from synthetic polymers like PGA, PLA, and PDO, allows for effective wound closure without the need for removal. Understanding the materials and properties of these sutures is essential for both medical professionals and patients. The choice of suture material depends on the specific needs of the surgical procedure and the desired absorption rate. While catgut remains in use, synthetic polymers are increasingly the preferred choice for their reliability and reduced risk of complications.