SMB Cardiovascular suture needles meet the highest standards of modern surgery. Our supplier’s years of experience as a needle manufacturer and continuous technical development have resulted in the development of needles, which combine outstanding quality with functionality. As a result of continual development we offer a product, which combines a high strength needle with a finely honed and extra sharp point.

SMB Cardiovascular needles are made from special maraging steel conforming to ‘Custom 455’, duly age-hardened to around VPN 525 so as to give optimum strength & ductility after heat treatment. This grade of steel offers much greater strength and resistance to bending as compared with austenitic or martensitic grades of steel.

The Stiffness of the cardiovascular taper point needles is enhanced through either a ribbed body section or square flattening. Stiffness is objectively evaluated on a digital stiffness tester, which measures the force in grams for producing a given deformation of the needle.

The cardiovascular needles have a long taper ratio point, with superior penetration characteristics.

These maraging steel needles have superior cutting edge retention because of the higher hardness of the needle.

All cardiovascular needles are siliconised using Dow Corning silicone grade MD-4159, duly cured. The silicone coating considerably reduces tissue drag and enhances point durability.

The Sharpness of the cardiovascular needle point is measured on a specially developed sharpness comparator, which measures the actual penetration force required for the needle point to pierce a polyurethane film, which closely mimics human skin.

Our cardiovascular needles have been benchmarked against similar needles from other companies including B.Braun, Ethicon, Tyco-D&G, etc and score comparably in terms of (a) initial point sharpness; (b) retention of point sharpness; and (c) stiffness.

SMB Atraumatic Channel Needle are manufactured from superior quality martensitic grade stainless steel, conforming to AISI 420, equivalent to EN 56D or Werkstoffnummer 1.4031. Needles are hardened and tempered to a controlled hardness of VPN 525-625, which ensures adequate stiffness to withstand the pressure encountered in the suturing procedure while eliminating brittleness.

The composition of this grade of stainless steel is as follows:

C	0.32-0.40%
Si	1.00%max.
Mn	1.00%max.
p	0.04%max.
S	0.03%max.
Ni	0.60%max.
Cr	12.5-14.0%

The Atraumatic needles are polished to minimize micro-asperities on the surface by a series of mechanical polishing operations followed by electro-polishing. This reduces tissue drag during the suturing operation to a minimum

All Atraumatic needle points are machine-honed on special purpose machines to ensure the highest standards of sharpness of the point. The point profile, both in the case of taper point needles and cutting edge needles, is specially designed to be a convex profile, which minimizes tissue penetration force while preserving the strength of the needle point. This type of point profile is also resistant to 'feathering'.

In the case of cutting edge needles, the widest part of the point is just before the shank of the needle, thereby minimizing tissue drag once the point has penetrated. This type of point configuration is also referred to as a 'cobra head' point.

In channel-type atraumatic needles, the channels are cold forged to close tolerances to ensure that final dimensions of the channel correspond to the suture diameter. Furthermore, the needles manufactured are uniformly heat-treated. Most manufacturers anneal the channel end to avoid cracking during crimping. The metallurgy of needles permits a hardened channel to be crimped satisfactorily without any problems; this results in uniform metallurgy of the needle and thereby improved corrosion resistance as well as resistance to bending.

A strict Quality Control protocol is followed at each stage of manufacture. The test done include point sharpness testing, which is carried out on a specially designed digital sharpness comparator, which measures the force (in grammes) required for penetrating of the needle point through a special polyurethane diaphragm. The polyurethane material is selected as it closely mimics the characteristics of human skin.

The stiffness of the needles is also measured with a special digital tester, which enables the Force Vs Displacement of the needle to be plotted and which also determines whether the needle has regained it's original shape without any permanent set having taken place.

Random samples of atraumatic needles' are drawn and test-attached with a suture after which they are subjected to pull-out strength testing in a digital tensilometer to ensure that USP standards are met.