Understanding How Absorbable Sutures Work and How Long They Last

In veterinary surgery, every small detail can make a big difference in how well an animal heals. From surgical precision to postoperative care, one critical factor that often determines success is the type of suture used, particularly absorbable sutures.

Absorbable sutures are designed to support tissues temporarily and then gradually break down inside the body as healing progresses. They’re a cornerstone of modern veterinary medicine, allowing a safer internal wound management.

But how long do absorbable sutures last? How do they dissolve? And how can veterinarians ensure proper wound healing while minimizing complications like infection or swelling?

In this guide, we’ll explore the science, timeline, and practical aspects behind the absorbable sutures.

What Are Absorbable Sutures?

Absorbable sutures are sterile surgical threads made from natural or synthetic polymer materials that degrade safely inside the body after serving their purpose. Unlike non-absorbable sutures (like nylon or silk), which must be manually removed, absorbable sutures dissolve naturally through biological or chemical processes.

Veterinary surgeons use absorbable sutures for internal closures, such as in soft tissue, gastrointestinal, or orthopedic surgeries, anywhere that removing stitches would be impractical or cause additional trauma.

These sutures act as temporary scaffolds, maintaining tissue integrity while healing occurs. Once the tissue regains strength, the suture is broken down into harmless byproducts (like water and carbon dioxide), which the body absorbs and excretes naturally.

How Does Absorbable Sutures Work?

The mechanism behind how absorbable sutures work depends on their composition, whether they’re made from synthetic polymers or natural materials like purified catgut.

There are two main degradation processes:

Hydrolysis (Synthetic Sutures)

Synthetic sutures such as ASSUFIL® (Polyglycolic Acid – PGA), MONOFIL® (Polyglyconate), and ASSUFIL Monofilament® (Polydioxanone – PDO) degrade through a hydrolytic process. In this mechanism, water molecules gradually break down the polymer chains, leading to a controlled reduction in tensile strength over time until the suture is completely absorbed. 

This hydrolytic breakdown is predictable, clean, and associated with minimal tissue inflammation, making synthetic absorbable sutures ideal for veterinary surgeries that require long-term support and biocompatibility.

Enzymatic Absorption (Natural Sutures)

Natural materials such as ASSUCROM® (Chromic Catgut) dissolve through enzymatic activity. Here, the animal’s body produces proteolytic enzymes that digest the suture material, similar to how it processes natural collagen. While this method provides fast absorption and excellent handling, it’s less predictable than hydrolysis, as it can vary with each animal’s enzyme levels, tissue health, and local inflammation response.

Both synthetic and natural absorbable sutures play crucial roles in modern veterinary medicine, the key is matching each product’s absorption profile and mechanical strength to the animal’s healing needs and the surgical site.

Common Materials Used in Absorbable Sutures

Our veterinary line features several high-quality absorbable sutures designed to meet diverse surgical needs. Each material offers distinct handling, strength, and absorption properties.

Material	Type	Absorption Time	Key Characteristics
Polydioxanone (PDO)	Synthetic Monofilament	180–210 days	Long-term strength, minimal tissue reaction, ideal for orthopedic and tendon repair
Polyglycolic Acid (PGA)	Synthetic Braided & Coated	60–90 days	Excellent knot security, mid-term absorption, smooth handling
Polyglyconate	Synthetic Monofilament	90–120 days	Balanced flexibility and durability, good for fascia and internal soft tissues
Polylactic Acid (PLA)	Synthetic Monofilament	60–120 days	Biocompatible, smooth passage through tissue, controlled degradation
Purified Catgut (Chromic Catgut)	Natural Multifilament	90–120 days (with tensile strength loss in 15-20 days from implantation)	Fast absorption, flexible, widely used in mucosal or soft tissue surgery

Each suture type aligns with specific veterinary procedures from short-term tissue support in skin closures to long-term structural reinforcement in orthopedic cases.

How Long Do Absorbable Sutures Last?

The longevity of absorbable sutures varies by material, tissue type, and patient condition. Generally, sutures last from a few days to several months inside the body before fully dissolving.

Below is a breakdown of average timelines:

• Chromic Catgut: 90–120 days
  Ideal for mucosal tissues, catgut breaks down quickly through enzymatic digestion.

   

• PGA (Polyglycolic Acid): 60–90 days
  Provides consistent absorption through hydrolysis, suitable for internal soft tissue repairs.

   

• PGCL / Polyglyconate: 90–120 days
  Offers smooth handling and predictable mid-term support.

   

• PDO (Polydioxanone): 180–210 days
  Retains strength the longest, used in fascia, tendon, or orthopedic surgeries.

   

The tensile strength (how long the suture holds tissue) is distinct from absorption time. For example:

• Chromic Catgut with tensile strength loss in 15-20 days from implantation,
• PGA maintains ~70–80% strength for the first week,
• PGCL retains 50–70% by two weeks,
• PDO holds ~80% for up to four weeks.

This gradual loss ensures the wound remains supported during critical healing stages before the suture completely disappears.

The Science of Absorption: Step-by-Step

1. Implantation

When the surgeon inserts absorbable sutures into tissue, they act immediately to close the wound and maintain tension.

2. Hydration

Within hours, body fluids begin penetrating the suture, initiating hydrolysis (for synthetics) or enzymatic digestion (for catgut).

3. Degradation

Molecular bonds start breaking down. For synthetic materials, hydrolysis leads to smaller fragments of polymers; for catgut, enzymes digest collagen fibers.

4. Strength Loss

Over days or weeks, the suture gradually loses tensile strength as tissue regains integrity. The rate of loss depends on polymer type, temperature, and pH balance.

5. Absorption

Finally, the degraded fragments are absorbed by surrounding tissues and metabolized or excreted. The entire process leaves behind no foreign residue.

How Long Does It Take for Sutures to Dissolve in Veterinary Patients?

The absorption timeline depends on multiple clinical and physiological factors:

• Species and Metabolism:
  Cats and dogs metabolize materials differently. Fast metabolism accelerates suture breakdown.

   

• Wound Environment:
  High humidity, infection, or inflammation increase enzymatic activity, speeding up absorption.

   

• Tissue Type:
  Well-vascularized tissues (like the mouth or mucosa) dissolve sutures faster than low-blood-supply areas (like tendons).

   

• Suture Composition:
  Synthetic polymer materials such as PDO and PGA break down more predictably, while natural catgut dissolves variably depending on local enzyme levels.

   

Comparing Absorbable vs Non-Absorbable Sutures

Feature	Absorbable Sutures	Non-Absorbable Sutures
Duration	Gradually dissolve (10–210 days)	Permanent or require removal
Common Materials	PDO, PGA, PGCL, Catgut	Nylon, Silk, Polyester
Tissue Reaction	Minimal (synthetic), mild (natural)	Very low
Ideal For	Internal tissues, fascia, ligaments	External skin closures
Removal Required	No	Yes
Risk of Infection	Low (monofilament)	Low, but prolonged presence increases risk

For most veterinary internal procedures, absorbable sutures are preferred. External wounds, however, often benefit from non-absorbable sutures, staples, or glue depending on location and tension.

Wound Healing and Absorbable Sutures

Understanding how long absorbable sutures last also requires knowing how wounds heal.
Veterinary wound healing occurs in three overlapping stages:

1. Inflammatory Phase (Days 1–5)
   The body initiates clotting, redness, and mild swelling. This is a natural immune response. Sutures provide essential tension support at this stage.

    

2. Proliferative Phase (Days 5–14)
   Fibroblasts produce collagen, new capillaries form, and tissues begin to close. Suture strength remains critical for alignment and wound stability.

    

3. Remodeling Phase (Weeks 2–8+)
   Collagen reorganizes, increasing tissue strength. Absorbable sutures begin losing tensile strength and eventually dissolve completely.
   

For large or slow-healing animals, like older dogs or horses, long-term sutures such as PDO are essential to provide extended support during this process.

Conclusion – Future of Absorbable Sutures in Veterinary Medicine

The veterinary surgical landscape is rapidly evolving toward precision medicine, bioactive materials, and knotless solutions like barbed sutures. Assut Europe’s innovations, including Filbloc® knotless sutures, represent the next generation of efficient, infection-resistant wound closure technology.

With continued R&D investment, Assut Europe aims to expand advanced suture lines that improve efficiency, safety, and surgical performance in modern veterinary practice.

So, how long do absorbable sutures last? The answer depends on the material, from Chromic Catgut’s 90–120 days, with tensile strength loss in 15-20 days to Polydioxanone’s 210 days. Understanding how absorbable sutures work, what they’re made of, and how they interact with tissue is essential for ensuring smooth, complication-free healing.

In veterinary medicine, absorbable sutures minimize stress for both patients and surgeons, enabling faster recovery, lower infection risk, and fewer post-surgical interventions.

Contact us whether you’re performing a soft-tissue repair, orthopedic surgery, or internal closure, Gexfix International Corp., in partnership with Assut Europe S.P.A., provides world-class absorbable sutures, adhesives, and staplers designed for precision and reliability.

Frequently Asked Questions (FAQs)

What is the life of absorbable sutures?

Absorbable sutures typically last anywhere from 10 days to 210 days, depending on their composition. For example, PGA dissolves within weeks, while Polydioxanone (PDO) or ASSUFIL Monofilament® can provide support for up to six months in slow-healing tissues.

Are dissolvable stitches as strong as regular stitches?

Yes, high-quality synthetic absorbable sutures such as ASSUFIL® (PGA) or MONOFIL® (Polyglyconate) offer exceptional tensile strength comparable to non-absorbable sutures. They maintain wound closure effectively during the critical healing phase before naturally degrading, ensuring reliable performance without requiring removal.

How to dissolve dissolvable stitches faster?

Absorption rate depends on body temperature, tissue health, and circulation. Warm, well-vascularized tissues accelerate dissolution, while infection or poor blood flow slows it. Never attempt to dissolve sutures manually, allow natural enzymatic or hydrolytic processes to occur safely under veterinary supervision.

What is the internal stitch's healing time? 

Internal healing varies with tissue type and patient health. In most animals, soft tissues heal within 10–21 days, while tendons or fascia require weeks to months. PDO sutures provide long-term tensile strength, ensuring stable closure throughout recovery.

Do dissolvable stitches fall out? 

Yes, as absorbable sutures lose integrity, remnants may loosen and fall out naturally. This typically happens after internal breakdown is nearly complete. Avoid pulling them, let the body expel remaining fibers under veterinary guidance to prevent irritation or infection.