Polydioxanone (PDO) threads are absorbable, medical-grade sutures repurposed in aesthetic medicine for non-surgical skin lifting and rejuvenation. This minimally invasive procedure involves inserting threads into the skin’s subdermal layer to provide mechanical support and stimulate biological regeneration. A common concern is whether the body’s reaction to this foreign material results in unwanted, permanent scar tissue. The answer lies in understanding the specific, controlled biological mechanism PDO threads are designed to activate.
The Body’s Expected Response to PDO Material
When a PDO thread is placed beneath the skin, the body recognizes it as a foreign material, initiating a localized, mild inflammatory response. This reaction is the deliberate biological trigger that makes the thread lift procedure effective for long-term skin quality improvement. The inflammation attracts specialized cells, particularly fibroblasts, to the area surrounding the thread.
These fibroblasts are the body’s natural collagen-producing factories. They cluster around the implanted thread and begin the process of neocollagenesis, which is the formation of new collagen. This controlled healing mechanism results in a dense, supportive matrix of protein fibers that acts as an internal scaffold.
The PDO material is a polymer that is fully hydrolyzed by the body over time, typically dissolving into harmless compounds within six to nine months. The biological response is temporary and terminates once the foreign material is completely absorbed. The newly formed collagen network remains, providing sustained lift and firmness to the treated tissues.
Distinguishing Controlled Collagen Formation from Scar Tissue
The structural support created by PDO threads is a form of healing response known as controlled fibrosis, which is fundamentally different from pathological scar tissue. Fibrosis is the general term for the formation of fibrous connective tissue following an injury. In a PDO thread lift, this process is organized and intended to produce a healthier dermal matrix.
Normal skin tissue has a basket-weave arrangement of collagen fibers, providing elasticity and strength. The neocollagenesis stimulated by PDO threads aims to regenerate a similar, organized collagen network, improving the density and resilience of the skin.
In contrast, pathological scar tissue, such as hypertrophic scars or keloids, is characterized by an overproduction of dense, disorganized collagen fibers that extend beyond the original injury site. This excessive, misaligned collagen lacks the functional quality of native tissue, resulting in a raised, firm, and persistent mark.
Because the PDO material is fully bio-absorbed, the stimulus for the foreign body reaction is removed before a chronic, disorganized fibrous mass can form. The resulting firmness is a natural biological reinforcement, not a persistent, pathological scar.
Procedural and Patient Factors That Influence Tissue Reaction
While the material is designed to avoid pathological scarring, adverse tissue reactions can occur due to external variables, primarily related to procedural technique.
Procedural Technique
The depth of thread placement is a significant factor. Placing a thread too superficially can lead to the thread becoming visible or palpable beneath the skin. Improper placement can also cause temporary skin irregularities like puckering or dimpling, which cause localized inflammatory stress.
The total thread load, or the number and size of threads used, also influences the body’s reaction. Overwhelming the treated area with excessive threads can lead to a more pronounced or prolonged inflammatory response. This increases the possibility of a chronic foreign body reaction, such as the formation of inflammatory nodules or granulomas, which deviates from controlled fibrosis.
Patient Biology
Patient biology plays a determining role, as individuals with a known predisposition to forming hypertrophic scars or keloids are more likely to exhibit an excessive fibrous reaction to skin trauma. Furthermore, any post-procedure infection or mechanical stress that disrupts the early healing phase can prolong inflammation. Chronic inflammation is a known precursor to disorganized and excessive tissue formation, emphasizing the importance of sterile technique and diligent aftercare.