WO2015033043A1

WO2015033043A1 - Implantable prosthesis whose non-adhesive part has an amorphous polymer

Info

Publication number: WO2015033043A1
Application number: PCT/FR2014/052129
Authority: WO
Inventors: Gilles Solecki; Mathilde Barlian; Stephane Noel
Original assignee: Cousin Biotech
Priority date: 2013-09-09
Filing date: 2014-08-27
Publication date: 2015-03-12
Also published as: FR3010303A1; FR3010303B1; EP3043742A1

Abstract

The invention relates to an implantable prosthesis (10) having an adhesive part (12), which is designed to form adherences with organic tissues and is composed of a knit (12) with at least a first non-resorbable monofilament (14), and a non-adhesive part (18), which inhibits the formation of adherences with organic tissues and is rigidly connected to the adhesive part. The invention is characterized in that the non-adhesive part (18) has at least a first layer (20) composed of an amorphous polymer and bonded at least to the first non-resorbable monofilament (14) of the adhesive part.

Description

IMPLANTABLE PROSTHESIS WITH NON-ADHERENT PORTION COMPRISING AN AMORPHOUS POLYMER

Background of the invention

The present invention relates to the field of medical devices intended to be placed in the body of a patient, and in particular a prosthesis intended to be implanted in the peritoneal cavity of the patient, between the peritoneum and the viscera, in order to repair the abdominal wall.

Traditionally, such an implantable prosthesis comprises:

an adherent portion configured to form adhesions with organic tissues of the peritoneum, the adherent portion consisting of a knit having at least a first non-absorbable monofilament; a non-adherent part, inhibiting the formation of adhesions with organic tissues of the viscera, integral with the adherent part.

Such a prosthesis is described in particular in US 6,270,530, which discloses a prosthesis made of a knitted fabric whose son forming meshes are melted on an expanded PTFE membrane. The adhesion of the knitted surface to the membrane is obtained by melting the non-resorbable polypropylene monofilament constituting the knit stitches on the surface of the expanded PTFE membrane and by the flow of the molten polypropylene into the porosity of the membrane, and this without melting of said membrane.

Although this technique has the advantage of improving the adhesion of the expanded PTFE membrane with polypropylene, it nevertheless has the drawback of considerably reducing the mechanical strength of the adhering part. To solve this problem, US 6,270,530 proposes to use a textile composed of two mesh surfaces attached to each other, only one of the two surfaces being melted on the expanded PTFE membrane. This solution, however, has the disadvantage of doubling the amount of implanted material, which has the consequence of increasing the cost of the prosthesis, and to stiffen the latter which can no longer be applied intraperitoneally.

The document EP 2 280 664 proposes, in relation to US Pat. No. 6,270,530, a prosthesis comprising filaments projecting from the mesh surface, which are melted on the expanded PTFE membrane, and this, in particular in order to avoid weaken the mesh surface that is not melted. This solution however has the disadvantage of adding material to the mesh surface whose purpose is to strengthen the abdominal wall. Another disadvantage is that the membrane has areas of weakness between the protruding filaments. Fragile areas are due to the presence of voids of material shown in Figure 3 of EP 2 280 664. Each space is located between two adjacent filaments protruding and between the mesh surface and the membrane. The prosthesis being manipulated by the clamps and rubbing against the edge and the inner wall of the trocar used, it is conceivable that the membrane may perforate or tear during handling.

Object and summary of the invention

An object of the present invention is to overcome the aforementioned drawbacks by providing an implantable prosthesis that is both flexible and robust.

The invention achieves its object by the fact that the non-adherent part comprises at least a first layer consisting of an amorphous polymer which is bonded at least with the first non-absorbable monofilament of the adherent part, and the non-adherent part comprises in addition a second layer consisting of a semi-crystalline polymer, arranged so that the first layer is located between the second layer and the knit of the adherent part.

The collage is made without melting the first monofilament. The inventors have found that the use of an amorphous polymer allowed an adhesion with the first non-absorbable monofilament without fusion of the latter.

The amorphous polymer is advantageously a thermoplastic polymer.

Since the polymer is amorphous, it has a glass transition temperature, but no melting point. The adhesion between the first layer and the non-resorbable monofilament is when the amorphous polymer is in its rubbery state. This rubbery state is one of the known features of amorphous polymers that intervene above their glass transition temperature.

According to an advantageous embodiment, the first layer consisting of an amorphous polymer is heat-bonded at least with the first non-resorbable monofilament of the adherent part.

To do this, the first layer made of an amorphous polymer on the first non-resorbable monofilament is thermocoated. According to the invention, the heat-sealing is performed without exceeding the melting temperature of the first non-absorbable monofilament. It is therefore understood that, according to the invention, the joining between the non-adherent part and the adherent part is obtained by adhesion of the first layer at least with the first monofilament, the latter not melting.

It is also understood that the glass transition temperature of the amorphous polymer is advantageously less than the melting temperature of the first non-resorbable monofilament.

The implantable prosthesis according to the invention may therefore advantageously be manufactured by hot rolling of the adherent part with the non-adherent part, by applying a pressure and a temperature greater than the glass transition temperature of the amorphous polymer, but lower than the temperature. melting of the first nonabsorbable monofilament. This allows the adhesion of the coating non-adherent without fusion of the filaments composing the knit, which makes it possible to maintain the integrity of the porosity and the mechanical strength of the knit.

Advantageously, the amorphous polymer is a thermoplastic amorphous polymer whose glass transition temperature is between 40 ° C and 80 ° C. The first monofilament has a melting point of between 140 ° C. and 180 ° C.

Preferably, the first layer is made of amorphous polylactide.

This amorphous polylactide is a thermoplastic polymer which has a glass transition temperature between 55 ° C and 60 ° C (temperature measured according to ASTM D3418), but has no melting temperature because of its amorphous state.

More preferably, the amorphous polymer of the first layer consists of L-lactide, D-lactide and meso-lactide monomer units, with a weight percent of D-lactide and / or mesolactide monomer units in the higher amorphous polymer. or equal to 8%.

Preferably, the weight percentage of D-lactide and / or mesolactide monomer units in the amorphous polymer is less than 15%.

According to an advantageous embodiment, the knit further comprises a second monofilament consisting of a semi-crystalline polymer.

Preferably, the second monofilament is made of semi-crystalline polylactide.

More preferably, the second semicrystalline polylactide monofilament is composed of L-lactide, D-lactide and mesolactide monomer units, with a weight percentage of D-lactide and / or meso-lactide monomer units in the polylactide. semi-crystalline less than or equal to 2%.

In this embodiment, the melting point of the first and second monofilaments is preferably less than or equal to 180 ° C. Advantageously, the melting point of the first and second monofilaments is greater than the glass transition temperature of the amorphous polymer.

According to a variant, the non-adherent portion further comprises another layer, identical and integral with the first layer. This other layer and the first layer consist of two separate films which are attached to each other during the manufacture of the prosthesis. An advantage of using two films to form the non-adherent part is to make the latter more resistant to performance and tearing.

Advantageously, the first and second layers of the non-adherent portion of the prosthesis are integral with each other.

Preferably, the non-adherent portion further comprises a third layer consisting of an amorphous polymer, arranged such that the second layer is located between the first layer and the third layer.

Preferably, the first and third layers consist of amorphous polylactide, while the second layer consists of semi-crystalline polylactide.

Preferably, these first, second and third layers together form a single film. According to one variant, the non-adherent part comprises two such integral and superposed films. Here again, the interest of these two films is to reduce the risk of perforation.

Preferably, the thickness of each of the films is between 15 and 40 micrometers.

Still preferably, the non-resorbable monofilament is polypropylene.

The invention also relates to a method for manufacturing an implantable prosthesis according to the invention comprising: a step during which at least one film is provided comprising a first layer consisting of an amorphous polymer, and a knit comprising at least one non-resorbable monofilament;

a step of bonding said first layer consisting of an amorphous polymer with at least the non-resorbable monofilament of the knit.

Advantageously, the bonding step comprises a heat-bonding step of said first layer consisting of an amorphous polymer with at least the non-resorbable monofilament of the knit.

The first layer is heat-bonded to the nonabsorbable monofilament of the knit, without exceeding the melting point of the nonabsorbable monofilament.

Thus, during the heat-sealing step, the amorphous polymer is in its rubbery state and adheres with the monofilament of the knit. After cooling, a solid bond is obtained between the film, constituting the non-adherent part of the prosthesis, and the knit constituting the adhering part.

Preferably, the heat-sealing step is carried out by hot rolling the film with the knitting fabric, applying a temperature of between 110 ° C. and 170 ° C. to the film. The rolling temperature is however lower than the melting temperature of the monofilament.

A pressure of between 13 N / cm 2 and 60 N / cm 2 is preferably applied during rolling, preferably for a time of between 0.5 seconds and 10 seconds.

Brief description of the drawings

The invention will be better understood on reading the following description of embodiments of the invention given as non-limiting examples, with reference to the accompanying drawings, in which: Figure 1 is a sectional side view of a prosthesis of the prior art;

Figure 2 is a sectional side view of a first embodiment of the invention, wherein the non-adherent portion of the prosthesis comprises two amorphous polymer films contiguous to each other;

Figure 3 is a sectional side view of a second embodiment of the invention, wherein the non-adherent portion of the prosthesis consists of two contiguous films, each film having three layers; and

FIG. 4 illustrates an exemplary manufacturing method according to the invention of the prosthesis of FIG. 2.

Detailed description of the invention

FIG. 1 shows an implantable prosthesis 1 of the prior art comprising an adherent part 2 configured to form adhesions with organic tissues, in particular peritoneum, the adherent part consisting of a knit comprising at least one filament not resorb ble 3.

The implantable prosthesis 1 furthermore comprises a non-adherent part 4, which inhibits the formation of adhesion with organic tissues, which is integral with the adhering part. In this prior art, the non-adherent portion 4 consists of an expanded PTFE membrane comprising porosities. As can be seen in FIG. 1, a portion 3a of the mesh 3 is melted in the porosity of the membrane 4.

With the help of Figure 2, we will describe a first embodiment of the implantable prosthesis according to the present invention.

In this first embodiment, the implantable prosthesis 10 comprises an adherent portion 12 which is configured to form adhesions with organic tissues, including peritoneum. This adhering part 12 consists of a knit forming a mesh which is composed of a first monofilament 14 and a second monofilament 16.

In this first embodiment, the knit is a chain or raschel type mesh surface.

The first monofilament is non-absorbable. It is made of semi-crystalline polypropylene and has a diameter of between 0.10 mm and 0.20 mm. In this example, its melting point is substantially equal to 150 ° C.

The second monofilament is made of semi-crystalline polylactide and has a diameter of between 0.10 mm and 0.20 mm. It has meanwhile a melting point substantially equal to 180 ° C. More specifically, the second monofilament 16 of polylactide is a semicrystalline polymer consisting of L-lactide, D-lactide and meso-lactide monomer units with a weight percentage of D-lactide and / or meso-lactide monomer units in the semi-crystalline polymer less than 2%.

The implantable prosthesis 10 further includes a non-adherent portion 18, configured to inhibit adhesion formation with the organic tissues of the viscera. As will be explained in more detail below, the non-adherent portion 18 is integral with the adhering portion 12.

According to the invention, the non-adherent portion 18 comprises a first layer 20 consisting of an amorphous polymer which is bonded with the first non-resorbable monofilament 14, as well as with the second monofilament 16 of the knit 12 of the adhering part 12 .

In this example, the first layer 20 is made of an amorphous thermoplastic polymer which is an amorphous polylactide.

In this example, the amorphous polymer of the first layer 20 consists of L-lactide, D-lactide and meso-lactide monomer units, with a weight percentage of D-lactide monomer units and / or mesolactide in the amorphous polymer greater than or equal to 8%. In this example, the weight percentage of D-lactide and / or meso-lactide monomer units in the amorphous polymer is of the order of 10%.

In this example, the polymer of the first layer is synthesized by ring-opening polymerization from the lactide isomers of L-lactide, D-lactide or meso-lactide.

The amorphous polylactide polymer used has a glass transition temperature between 55 ° C and 60 ° C (temperatures measured according to ASTM D3418). The amorphous polylactide therefore does not have a melting temperature because of its amorphous state.

In the example of FIG. 2, the first layer 20 constitutes a first film A.

In this example, the first layer 20 is heat sealed to the first and second monofilaments.

Furthermore, the non-adherent portion further comprises another layer 20 'also made of amorphous polylactide, this other layer constituting a second film B integral with and superimposed on the first layer 20.

It is therefore understood that in the example of Figure 2, the non-adherent portion 18 consists of two separate films from one another, which are integral with each other together. In this example, the thickness of each film A, B is of the order of 25 microns.

With the help of Figure 3, we will describe a second embodiment of the implantable prosthesis 100 according to the invention.

Similarly to the first embodiment, the implantable prosthesis 100 comprises an adherent portion 112 configured to form adhesions with organic tissues, the adherent portion consisting of a knit comprising at least a first non-resorbable monofilament 114. In this example , the first monofilament is made of semi-crystalline polypropylene and has a diameter of the order of 0.1 mm.

The implantable prosthesis 100 further comprises a non-adherent portion 118, inhibiting adhesion formation with the organic tissues of the viscera, which is also integral with the adherent portion.

In this second embodiment, the non-adherent portion 118 comprises a first film A comprising a first layer 120 consisting of an amorphous thermoplastic polymer which is bonded, by heat-sealing, to the first and second monofilaments 114, 116 of the adherent portion 112.

The first film A of the non-adherent part 118 further comprises a second layer 140 which is made of a semicrystalline polymer, arranged so that the first layer 120 is located between the second layer 140 and the knit 112 of the part adherent.

In this example, the semicrystalline polylactide constituting the second layer has a weight percentage of D-lactide and / or meso-lactide monomer units in the semi-crystalline polylactide of less than 2%.

The first film A of the non-adherent part further comprises a third layer 142 consisting of an amorphous polymer, in this case an amorphous polylactide thermoplastic polymer. This third layer is arranged in such a way that the second layer is situated between the first layer 120 and the third layer 142. It is thus clear that the second layer 140 is sandwiched between the first layer 120 and the third layer 142. The materials constituent of the first 120 and third 142 layers are therefore identical.

Film A has in this example a thickness of the order of 25 micrometers. In this example, the non-adherent portion 118 further comprises a second film B identical and integral with the first film A. It is therefore understood that the second film B is also composed of the three aforementioned layers. The film B also has a thickness of the order of 25 micrometers.

The composition of the first and second monofilaments is identical to that of the first embodiment.

FIG. 4 illustrates a mode of implementation of the manufacturing method according to the invention of the implantable prosthesis 10 according to the first embodiment illustrated in FIG.

This method comprises a step during which the two abovementioned films A and B are provided, and a knit 12 comprising the first nonabsorbable polypropylene monofilament 14 and the second monofilament 16.

The two films and the knit are superimposed before being passed through a rolling mill in order to undergo a heat-sealing step in which the two films A, B are placed side by side, and in which the first layer of polylactide amorphous, which is then in its rubbery state, is thermocollated with at least the nonabsorbable filament of the knit.

In this process, heat-sealing is achieved by hot rolling is performed by providing a rolling pressure of between 13 newton / cm ² and 60 newton / cm ² while applying a temperature of 145 ° C on the non-adherent part, and this for a period of between 0.5 and 10 seconds. This temperature is lower than the melting temperature of the monofilaments.

Claims

1. Implantable prosthesis (10,100) comprising:

an adherent portion (12,112) configured to form adhesions with organic fabrics, the adherent portion being comprised of a knit (12) having at least a first non-absorbable monofilament (14,114);

a non-adherent part (18,118), inhibiting the formation of adhesions with organic tissues, integral with the adherent part;

the implantable prosthesis being characterized in that the non-adherent part (18, 118) comprises at least a first layer (20, 120) made of an amorphous polymer which is bonded at least with the first non-absorbable monofilament of the adhering part, and in that the non-adhering portion (118) further comprises a second semicrystalline polymer layer (140) disposed so that the first layer (120) is located between the second layer (140) and the knit ( 112) of the adhering part.

2. The implantable prosthesis according to claim 1, wherein the first layer (20,120) consisting of an amorphous polymer is heat-sealed at least with the first non-resorbable monofilament (14,114) of the adherent portion.

The implantable prosthesis of claim 1 or 2, wherein the first layer (20, 120) is made of amorphous polylactide.

The implantable prosthesis according to claim 3, wherein the amorphous polymer of the first layer (20,120) is constituted of L-lactide, D-lactide and meso-lactide monomer units, with a weight percentage of D-lactide and / or mesolactide monomer units in the amorphous polymer greater than or equal to 8%.

The implantable prosthesis of claim 4, wherein the weight percent of D-lactide and / or mesolactide monomer units in the amorphous polymer is less than 15%.

Implantable prosthesis according to any one of claims 1 to

5, wherein the knit further comprises at least a second monofilament (16, 116) made of a semi-crystalline polymer.

The implantable prosthesis of claim 6, wherein the second monofilament (16,116) is made of semicrystalline polylactide.

The implantable prosthesis according to claim 7, wherein the second semicrystalline polylactide monofilament (16,116) is composed of L-lactide, D-lactide and meso-lactide monomer units, and in that the percentage by weight of units D-lactide and / or meso-lactide monomers in the semi-crystalline polylactide is less than or equal to 2%.

Implantable prosthesis according to any one of claims 6 to

8, wherein the melting point of the first and second monofilaments (14,16; 114,116) is greater than the glass transition temperature of the amorphous polymer.

Implantable prosthesis according to any one of claims 1 to

9, in which the non-adhering portion further comprises a third layer (142) formed of an amorphous polymer, arranged such that the second layer is located between the first layer (120) and the third layer (142).

The implantable prosthesis of claim 10, wherein the first and third layers (120,142) are of amorphous polylactide, while the second layer (140) is of semi-crystalline polylactide.

Implantable prosthesis according to one of claims 1 to

11, in which the non-adherent portion consists of at least two films (A, B) glued to each other.

The implantable prosthesis of claim 12, wherein the thickness of each of the films (A, B) is between 15 and 40 microns.

The implantable prosthesis according to any one of the preceding claims, wherein the first nonabsorbable monofilament (14, 16) is polypropylene.

The method of manufacturing an implantable prosthesis according to any one of claims 1 to 14, comprising:

a step during which at least one film is provided comprising at least a first layer consisting of an amorphous polymer and a knit comprising at least one non-resorbable monofilament;

16. The method of claim 15, wherein the bonding step comprises a heat-bonding step of said first layer consisting of an amorphous polymer with at least the non-resorbable monofilament of the knit.

17. The method of claim 16, wherein the heat sealing step is performed by hot rolling the film with the knit, applying a temperature between 110 ° C and 170 ° C on the film.