RO123135B1 - Non-absorbable surgical suture thread - Google Patents

Abstract

The invention relates to some non-absorbable braided threads for surgical sutures having a braided structure made of polyester threads having a linear density of 280 +- 6% dtex, comprising 48 +- 30% filaments with a twist of 360 +- 50 Z, or a linear density of 167 +- 6% dtex, having 48 +- 30% filaments with a twist of 250 +- 40 Z, or a linear density of 88 dtex +- 6%, comprising 34 +- 30% filaments with a twist of 350 +- 50 Z, made by braiding 12 threads which are twisted by three at 120 +- 20 twists/m, at a braid count of 200 +- 12 braids/10 cm, or by two at 150 +- 24 twists/m, at a braid count of 130 +- 8 braids/10 cm, with a bifilar joining at a joining ratio R1=4 and the tension of the threads on the spools of 0.10...0.30 cN/dtex.

Description

The invention relates to non-absorbable, braided yarns, intended for use in general surgery, for making sutures, and to a process for making them.

Making threads for surgical sutures, from non-absorbable biomaterials, is one of the research concerns that are currently being carried out worldwide.

There are known non-absorbable suture yarns used in general surgery, the so-called core-yarn yarns, which are obtained by braiding 12 polyester yarns around 4 polyester yarns, but which has the disadvantage that, during use in the operating block, they do not maintain dimensional stability at the ends, thus making the surgical act more difficult, which leads to the heavy manipulation of the cyst at the time of clinical placement.

There are also known two categories of yarns for non-absorbable sutures, with an apparent diameter of 420-589 pm, minimum breaking load 42 N, obtained by simultaneous braiding of 8 polyester yarns with the density of individual yarn lengths of 83 dtex / 32fx2-150 dtex / f32, and with an apparent diameter of 400-650 pm, the breaking load of at least 48 N, obtained by simultaneous braiding of 8 polyester yarns with the density of lengths of individual threads of 167 dtex / 32fx2, which has the disadvantage of the non-uniformity of the physical-mechanical characteristics (apparent diameter, density of product length, mass, number of braids / cm, load and elongation at break) along the length of the product, with a direct impact on the quality of the medical act (increased intervention times, the possibility of postoperative complications, etc.).

There is also known a multifilamentary yarn, braided, of non-absorbable material (WO 00/61202), consisting of a core and a blanket, used in the field of surgery, in making standard sutures, surgical nets or as an element - in support of various invasive medical procedures. The disadvantage of this thread is that the process of execution is laborious and expensive.

Also known is a thread for surgical sutures (RO 94978), consisting of at least three yarns 20 tex of flax fibers, having an average length of 45 ... 100 cm and a breaking load of 200 ... 500 cN. The disadvantage of this thread lies in the fact that it does not have the characteristics of uniformity and resistance suitable for making quality sutures.

The technical problem that this invention solves is to make non-absorbable wires for surgical sutures that have some constant structural characteristics throughout the length of the product (apparent diameter, mass) and to ensure a quality medical record.

Thread for surgical sutures, non-absorbable, according to the invention, having a braided structure of polyester yarn with a density of 280 + 6% dtex length, comprising 48 + 30% filaments with torsion 360 ± 50 Z, or with a density of length 167 ± 6% dtex , having 48 ± 30% filaments with 250 ± 40 Z torsion, or with 88 dtex ± 6% length density, comprising 34 ± 30% filaments with 350 ± 50 Z torsion, solves the aforementioned technical problem and eliminates the above disadvantages, by that is made by knitting 12 yarn, twisted three yarn with 120 ± 20 satin / m, with a braid of 200 ± 12 braid / 10cm, or two yarn with 150 ± 24 sat / m, with one tenth of the braid of 130 ± 8 cm / 10 cm, after a two-wire connection with a binding ratio R ₁ = 4, and a tension for the strands on the strands of 0,10-0,30 cN / dtex.

The process of realizing the structure, according to the invention, consists of: conditioning the polyester yarns for 24 hours, at a temperature of 22-25 ° C and a relative humidity of 65%, depositing the yarns on special braiding formats (tapping), with a wire voltage of 0.1-0.3 cN / dtex; the weaving of 12 wire systems in two-wire connection in a binding ratio of 4; the interphase finish and the finished product consisting of a succession of operations: extraction of oligomers from methylene chloride p a, for 3 hours, at a temperature of at least 40 ° C; washing with degreasing solution of sodium hydroxide, hydrosolvent and acetic acid at 60 ° C; disinfection in 1: 3 oxygenated water solution; successive rinses (3 cycles) in distilled water; drying

RO 123135 Β1 at maximum temperature 40 ° C, for 2-3 days; steaming at a maximum temperature of 120 ° C, 1 for 30 minutes; drying at a maximum temperature of 40 ° C for 24 hours; winding with a voltage of not more than 0.20 cN / dtex; thermofixation at 200 ° C for half an hour; reeling; 3 sections at a length of 1.4 m; cuts formed to the size of 3.5 cm; washing-degreasing formed in solution of sodium hydroxide, hydrosolvent and acetic acid, at 60 ° C; 5 successive rinses (3 cycles) in distilled water for 4 hours; drying at a maximum temperature of 40 ° C for 8 hours; format submission; washing-degreasing solution of sodium hydroxide, hydro-7 solvent and acetic acid at 60 ° C; disinfection in oxygenated water solution, 30%, for 4 hours; rinse (4 cycles) in distilled water; drying at a temperature of maximum 40 ° C, for 9 2-3 days; packaging and sterilization of the finished product by Co60 gamma irradiation, absorbed dose 27.6-37.5 KGy. 11

The invention has the following advantages:

- superior use of raw materials for medical purposes; 13

- ease of handling;

- reducing the financial efforts related to imports; 15

- the possibility to realize on the equipments provided with easily accessible materials.

The following are two examples of embodiments of the invention

Example 1. On a bobbin machine, the polyester yarn is deposited on a spool, with a density of length 280 ± 6% dtex. Having 48 ± 30% filaments 360 ± 5019

Z or 88 dtex ± 6% having 34 ± 30% filaments, torsion 350 ± 50 Z, being twisted 3 wires each with 120 ± 20 raz / m, with a tension of 0.20-0.30 cN / dtex.21

On a machine made of tubular products, it is realized the braiding of the 12 loops after a bifilar connection with a ratio of binding R _d = 4, with a braid thickness: 200 ± 1223 loops / 10cm and a tension for the threads on the loops of 0, 15-0.20 cN / dtex.

The resulting braided structure has the breaking strength of at least 100 N, the elongation at 25 breaks of maximum 60% and the apparent diameter in the range 620 ... 750 pm.

In order to obtain the non-absorbable sutures, usable in surgery, the woven structure 27 obtained is subjected to a complex process of interphase and final finishing, consisting of: extraction oligomers in methylene chloride p.a, for 3 hours, at a temperature of at least 40 ° C; 29 washing-degreasing in solution of sodium hydroxide, hydrosolvent and acetic acid, at 60 ° C; disinfection in 1: 3 oxygenated water solution; successive rinses (3 cycles) in distilled water 31; drying at a temperature of maximum 40 ° C, for 2-3 days; steaming at a maximum temperature of 120 ° C for 30 minutes; drying at a maximum temperature of 40 ° C for 24 33 hours; winding with a voltage of maximum 0.20 cN / dtex; thermofixation at 200 ° C for half an hour; reeling; sectioning to a length of 1.4 m; cuts formed to the size of 3.5 cm; 35 washing-degreasing formed in solution of sodium hydroxide, hydrosolvent and acetic acid at 60 ° C; successive rinses (3 cycles) in distilled water, for 4 hours; drying at 37 maximum temperature 40 ° C for 8 hours; format submission; washing-degreasing in solution of sodium hydroxide, hydrosolvent and acetic acid, at 60 ° C; disinfection in solution 39 of oxygenated water 30%, for 4 hours; rinse (4 cycles) in distilled water; drying at a temperature of maximum 40 ° C, for 2-3 days; packaging and sterilization finished product by gamma irradiation 41 Co60, absorbed dose 27.6-37.5 KGy.

Example 2. On a grooving machine, the filing 43 of polyester yarns, with a density of length 167 ± 6% dtex, having 48 ± 30% filaments 250 ± 40 Z or 88 dtex ± 6%, having 34 ± 30% filaments, torsion 350 ± 50 Z, being twisted 2 45 threads each with 150 ± 24 ras / m, with a tension of 0.15-0.23 cN / dtex.

RO 123135 Β1

On a machine made of tubular products, the twisting of the 12 threads is realized after a two-wire connection with a binding ratio 4, with a braid height: 130 ± 8 threads / 10 cm and a tension for the threads on the threading of 0,10- 0.18 cN / dtex.

The resulting braided structure has a breaking resistance of at least 65 N, an elongation at 5 breaks of maximum 60% and the apparent diameter in the range 480 ... 600 pm.

In order to obtain the non-absorbable sutures, usable in surgery, the braided structure obtained is subjected to a complex process of interphase and final finishing, as in Example 1.

Claims (3)

Claims 1 1. Thread for surgical sutures, having a braided structure of polyester yarns with 3 density of length 280 ± 6% dtex, comprising 48 ± 30% filaments with torsion 360 ± 50 Z, or having a density of length 167 ± 6% dtex, having 48 ± 30% filaments with torsion 5 250 ± 40 Z, or having a density of length 88 dtex ± 6%, comprising 34 ± 30% filaments with torsion 350 ± 50 Z, characterized by the fact that it is made by knitting 12 threads, 7 twisted three threads each with 120 ± 20 satins / m, with a braid thickness of 200 ± 12 widths / 10 cm, or two threads with 150 ± 24 satins / m , with a wedge height of 130 ± 8 m / 10 cm, after 9 a two-wire connection with a binding ratio Ri = 4, and a tension for the strands on the strands of 0.10-0.30 cN / dtex. 11 2. Surgical suture wire according to claim 1, characterized in that it has a rupture resistance of at least 65 N, an elongation at rupture of maximum 60% and a 13 diameter apparently in the range 480 ... 750 pm. 3. Process for making surgical suture wires, according to claims 1 and 15 2, characterized in that it comprises the following phases: - extraction of oligomers from methylene chloride p.a, for 3 hours, at a temperature of 17 minimum 40 ° C; - washing-degreasing in solution of sodium hydroxide, hydrosolvent and acetic acid, at 19 at 60 ° C; - disinfection in 1: 3 hydrogen peroxide solution, 21 - successive rinses (3 cycles) in distilled water; - drying at a temperature of maximum 40 ° C, for 2-3 days; 23 - steaming at a maximum temperature of 120 ° C for 30 minutes; - drying at a maximum temperature of 40 ° C for 24 hours; 25 - winding with a voltage of maximum 0,20 cN / dtex; - thermofixing at 200 ° C for half an hour; 27 - tooling; - sectioning to a length of 1.4 m; 29 - cuts formed to the size of 3.5 cm; - washing-degreasing formed in solution of sodium hydroxide, hydrosolvent and acetic acid, 31 at 60 ° C; - successive rinses (3 cycles) in distilled water, for 4 hours; 33 - drying at a temperature of maximum 40 ° C, for 8 hours; - format submission; 35 - washing-degreasing in solution of sodium hydroxide, hydrosolvent and acetic acid, at a temperature of 60 ° C, 37 - disinfection in oxygenated water solution, 30%, for 4 hours; - rinse (4 cycles) in distilled water, 39 - drying at a temperature of maximum 40 ° C, for 2-3 days; - packaging and sterilization of the finished product by Co60 gamma irradiation, absorbed dose 41 27.6-37.5 KGy.