Dissolvable stitches can be naturally made of intestinal linings of ruminant animals or synthetically made of polymers or copolymers. Regardless of what they're made of, they will all get absorbed by our bodies in due time.
However, depending on the type of material the sutures are made of, they will dissolve at different rates and also via different mechanisms. Please read carefully because there are many different kinds of dissolvable sutures. It also doesn't help that some of their names look incredibly similar to one another.
Table of dissolvable stitches materials
We've created a table below which organizes all of the absorbable stitches based on how they're made, the type of material used to make them and also how they dissolve.
Type of Suture | How its made | Type of material | How it dissolves |
|---|---|---|---|
Fast Gut | Natural | Animal intestines | Proteolytic enzymes |
Plain Gut | Natural | Animal intestines | Proteolytic enzymes |
Chromic Gut | Natural | Animal intestines | Proteolytic enzymes |
Polyglycolic acid | Synthetic | Polymers | Hydrolysis |
Polydioxanone | Synthetic | Polymers | Hydrolysis |
Polytrimethylene carbonate | Synthetic | Copolymers | Hydrolysis |
Polyglactin 910 | Synthetic | Copolymers | Hydrolysis |
Glycomer 631 | Synthetic | Copolymers | Hydrolysis |
Polyglytone 6211 | Synthetic | Copolymers | Hydrolysis |
Poliglecaprone | Synthetic | Copolymers | Hydrolysis |
The simplest way to think of them is by broadly categorizing them into three groups:
Group 1 - All natural
Group 2 - Synthetic polymers
Group 3 - Synthetic copolymers (multiple types of polymers)
If you attempt to look at each dissolvable suture individually and what they're made of, your head will spin based on the chemistry heavy terminology. Above is the simplest way that we can group them together and make sense of them.
Nonetheless, for completeness sake we will go into further depth for each type including what color they are so you know how to identify them.
Natural dissolvable stitches
The all natural dissolvable stitches called catgut are made of collagen that is derived from the small intestine of ruminant animals (cows, goats, & sheeps).
Contrary to its name, it is not actually made out of the guts of cats but rather ruminant animals instead. Since it is basically made of collagen, it is similar to food. That means it can be dissolved and absorbed just like collagenous foods.
Specifications:
Types: Plain gut, Fast gut, Chromic gut
Stitch color: Light yellow, gold, can be mistaken as white colored
Dissolution time: 5-14 days
Dissolution mechanism: Naturally dissolves by body's proteolytic enzymes.
The chromic gut sutures are commonly used for wisdom teeth stitches.
Dissolvable synthetic polymer sutures
Dissolvable synthetic polymer stitches are made of long chains of repeating monomers.
Polymer vs monomer:
Monomer - single molecule, often organic meaning it has carbon atoms.
Polymer - multiple monomers that are stringed together into a long chain.
In the case of sutures, you can think of the polymers as a long thread (no pun intended) of the same monomer repeating itself over and over again. They are connected to form a long string.
Two types of dissolvable polymer sutures:
Polyglycolic acid (Polysyn)
Polydioxanone (PDS)
Suture Name | Monomer | Stitch color | Dissolving time | Dissolving mechanism |
|---|---|---|---|---|
Polyglycolic acid | Glycolide | Violet | Hydrolysis | |
Polydioxanone | Paradioxanone | Violet | Hydrolysis |
Due to these polymers being dissolved via hydrolysis in lieu of proteolytic enzymatic degradation, there is less of a tissue inflammatory reaction. This characteristic is preferred by surgeons since it is less impeding upon the healing of the wound.
Dissolvable synthetic copolymer sutures
Dissolvable synthetic copolymer stitches are made of long chains of different polymers that are stitched together (no pun intended).
Copolymer vs polymer vs monomer:
Monomer - single molecule, often organic meaning it has carbon atoms.
Polymer - multiple monomers that are stringed together into a long chain.
Copolymer - multiple polymers that are stringed together into a long chain.
An alternative way to think of what these terms mean and what the sutures are is in terms of lego blocks.
Monomers are different colored lego blocks. A single monomer represents one lego block.
Polymers are multiple lego blocks of the SAME COLOR that are attached together.
Copolymers are multiple lego blocks of DIFFERENT COLORS that are attached together.
Suture Name | Copolymers | Stitch Color | Dissolving time | Dissolving Mechanism |
Polytrimethylene carbonate | Glycolide, Lactide, Trimethylene carbonate | Green | ||
Polyglactin 910 | Glycolide, Lactide | Violet | ||
Glycomer 631 | Glycolide, Paradioxanone, Trimethylene carbonate | Violet | Hydrolysis | |
Polyglytone 6211 | Glycolide, Caprolactone, Trimethylene carbonate, Lactide | Violet | Hydrolysis | |
Poliglecaprone | Glycolide, epsilon-capralactone | Violet |
A suture isn't a single molecule but rather a long strand of a combination of monomers stringed together. You may have also noticed that a lot of the dissolvable ones are violet/purple in color.
Takeaway
Dissolvable stitches are either synthetically made or naturally made from the intestines of ruminant animals. The synthetically made ones consist of either polymers or copolymers, which are essentially long strands of various monomers.
The natural sutures will dissolve via proteolytic enzymatic degradation while the synthetic ones all dissolve via hydrolysis. The latter produces less tissue inflammation while it breaks down so is currently preferred over the former.
