monofilament polyamide ethilon polyamide suture
Ethilon polyamide suture is a synthetic, absorbable material. It is made of a non-absorbable polyamide (nylon) with two absorbable polymers, glycolide and caprolactone. The ratio of the three materials can be varied to give different properties to the suture. Ethilon was developed by SulzerMedica in Switzerland in 1955.
How is it used ?
It’s used as an alternative material for permanent sutures because it has better tissue compatibility than silk and nylon (e.g. Vicryl/polyglactin 910). It is a viable alternative to silk or nylon sutures since it provides better knot security than the absorbable materials. This means there’s less tendency for the knots to work loose.
Ethilon is classified as a synthetic, absorbable suture material; it’s not absorbed in its entirety. This means that after placement, and subsequent absorption of the glycolide and caprolactone portions of the suture, part of the nylon core remains in place.
The types of Ethilon polyamide sutures are classified according to the composition of their polyamides. The three main types are, naturally-derived (polyamide 6), all-synthetic (polyamide 8) and a blend of both (polyamide 12).
Strength of properties
The strength properties of monofilament polyamide suture depend upon the type of polyamides used in construction. The natural polyamides are hydrolytic resistant, which implies that they can be processed with boiling water without decaying. Their tensile strength is more consistent than artificial polyamides due to their elongation at break, and compliance at break. The all-synthetic polyamides have a lower tensile strength than the natural polyamides due to the intermolecular bond within the polymer, which allows bond breakage at a smaller degree of elongation.
The strength properties of synthetic polyamide suture are limited by the molecular weight and the molecular weight distribution. The higher the molecular weight, the more efficient the result is when using ethylene glycol as a reactant to hydrogenate these molecules. The higher molecular weight obtained from this process leads to an increase in tensile strength. At low dosages (below 20 kg/m), it is possible to obtain both high tensile and elongation properties in synthetic polyamides. This is because of the amorphous nature of the polymer, which allows for a good entanglement between the molecules.
The optimal type of polyamide depends upon the application. Synthetic polyamides are widely used for their strength, high elongation and low micromoment tensile strength. Synthetic polyamides have been compared to natural fibers in their microhardness and resistance to degradation by amino acids during the healing process. Natural fibers are hydrolytic resistant. Their tensile strength is partly dependent on this characteristic, since they do not significantly change when subjected to boiling water without being degraded. Ethilon sutures are heat resistant, a factor that is important in the tissue integration if the sutures remain in place for a long time.
Ethilon polyamides are used in eye surgery, ophthalmologic surgery and various orthopedic procedures such as anterior cruciate ligament reconstruction and rotator cuff repair. It’s also used to repair tendons and ligaments thanks to its good knot security. Ethilon polyamide suture is used for tie-down procedures on patients with abdominal wounds and when low tensile strength polyethylene or polypropylene material is contraindicated.