DE3830005C1 - Sheet-like implant - Google Patents

Abstract

The invention relates to a sheet-like implant of an absorbable material which is characterised in that it comprises woven or knitted nets, strips or bands whose filaments or fibres are made of at least two different absorbable materials having different melting points which have been formed or pressed to give a sheet-like laminate after heating to a temperature above the melting point of the absorbable material having the lowest melting point and below the melting point of the other absorbable material having the highest melting point.

Description

The invention relates to a flat implant from resorbent material.

Such implants are for example from US-PS 37 39 773 known and have those known from DE-OS 36 33 742 Prostheses made of biocompatible polyester or polyethylene Plastics detached; they consist of flat or Velor-like products, for example in several layers or in a sponge-like structure for the treatment of burns or other skin damage and for other uses Find use. Because of their porosity, they can Tissue fluid absorb and gradually become tissue penetrates that after complete absorption of the implant its supporting or holding function takes over. Similar rag-like structures made of solidified felt Press surface smoothed fibers from resor Material that can be used are called hemostatic lobules used in which according to DE-OS 36 33 742 at the Fibers lying on the surface using a hot embossing roller the structure is pressed in and a smoother surface  surrender that clings closer to the wound. The The temperature of the embossing roller must prevent this Damage to the material naturally below the enamel point of the material.

However, these textile-like fabrics are because of their small thickness and lobe-like nature only limited applicable.

DE-PS 36 19 197 pillow-shaped implants are known the outer shell of a knitted tube made of resorbent baren filaments or fibers and with threads, fila elements, flakes or chips from a resorbable Material is filled; have these tubular pads a compressibility of at least 50% and become  Treatment of hernias used.

Ultimately, e.g. B. from US-PS 41 86 448 foam-like Implants made from a single absorbable polyglycol acid esters known; such spongy or foam like implants have the disadvantage that they still Verun cleaning based on the foaming required Contain ingredients that are incompatible with tissue; about that In addition, such foam-like implants have uniform absorption time.

A fundamental disadvantage of weaving, knitting or knitting monofilaments from resorbable material obtained flat implants is the fact that this material after cutting or ripping the flat Structure at least in the peripheral areas loses it unless you knit with complicated knitting machines produces solid fabrics whose mechanical strength leaves much to be desired.

The invention has for its object a flat To propose an implant that can be cut and sewn in is of considerable mechanical strength and yet is sufficiently porous to ingrow tissue to let and a different resor has beerability within the entire flat implant.

A flat implant is used to solve this task proposed according to the main claim, being particularly preferred Embodiments are listed in the subclaims.  

Surprisingly, it has been shown that a flat Implant made of woven, knitted or knitted nets, Stripes or ribbons made from at least two different ones absorbable materials with different enamel score that after heating to a temperature above the melting point of the absorbable material with the lowest melting point and below the melting point of the other absorbable material with high melting point point results in a flat composite, which due to the essentially superficial bonding of the individual Filaments can be cut, gives smooth cutting edges, has the desired strength and with respect to Ma width or pore size depending on the type of production can be designed.

Woven tapes can be used with advantage, for example in capsular ligament surgery of the knee joint and in number enough other cases in the field of osteosynthesis, in particular the higher mechanical strength and the longer in vivo strength of the sheet composite is an advantage.

In a particularly preferred embodiment, can close-meshed nets also with a felt layer made of resorbable bar material. Here either the woven, knitted or knitted material in front of the Warming with a fiber mixture of resorbable fibers in a length of, for example, 5 to 12 mm and then deformed or the already obtained flat Composite is made with the fiber mixture of resorbable Material with different melting points covered with felt  and then again, for example, 100 to 110 ° warmed up.

The advantage of these composite networks with a felt layer is based on the fact that the strips obtained through the felt surface are blood-tight and thus z. B. for Vessels for seam support or directly as a patch can be used.

Absorbable polymers with good physiological tolerance are known per se. Typical representatives are poly-p-di oxanones, which are sold under the name "PDS" and chemically, aliphatic poly-p- polyester are dioxanons that can be extruded into monofilaments and melt at 85 to 95 ° C; they are in "Ethicon OP Forum ", Issue 108 (1981) and in J. Pediatr. Ophthalmol. 13, 360-364 (1976).

Belong to another group of absorbable materials the polyglactins, which are a copolymer of glycolide and Lactides are and also extrude themselves into threads leave that under the name "Vicryl" (Wz) in the market available and in detail for example in "Ethicon OP Forum ", volume 96 (1978) and in J. Pediatr. Ophthalmol. 13, 360, 1976. Belong to this group also lactide-glycolide block copolymers according to DE-OS 28 49 785. These polyglactins have depending on the polymerization degrees a melting point of 180 to 200 ° C.  

Depending on the type of absorbable material and also depending the absorbability differs according to the degree of polymerization. It lies, for example, with the higher melting polyglactins in the range of 60 to 80 days and at the lower melting poly-p-dioxanones in a range of 200 Days. By appropriate mixture of the felt-like One can use implant-forming monofilaments or fibers the resorption time of the entire felt-like implant, the speed with which the implant is dismantled can be control.

A mixture of fibers of the is particularly preferred Poly-p-dioxanones with those of polyglactin in one Ratio of 5: 1 to 1:15 and especially in one 1: 3 ratio.

The fact that the fiber mixture within the different The melting points of the resorbable materials are heated and then deformed, there is a solidification of fibers from the higher melting resorbable Material by melting the filaments together or fibers of the lower absorbable material Melting point, so that a still porous, flat Structure is obtained.

In the following the invention with reference to drawings are explained in more detail; it shows

Figure 1 shows a section of a knitted composite material.

Fig. 2 is an illustration of the use of an inventive network;

Fig. 3 is a partially sectional view of a felt layer coated with composite network;

Figure 4a is a representation of the use of a strip OF INVENTION to the invention in the removal of an aneurysm.

FIG. 4b is a view similar to FIG. 4a via the use of a sheet-like implant according to the invention in closure of the lumen of an aneurysm.

example 1

A knitted fabric similar to FIG. 1 with a mesh size of 4 mm diameter was produced on a flat knitting machine, namely from mixed filaments consisting of an average of 10 filaments made of a polyglactin melting at 180 ° C. with a thread thickness of 60 dtex and 1 filament one at about 90 ° melting poly-p-dioxanons with a thread size of 20 dtex. This from the results shown in Fig. 1 filaments of polyglactin 2 a and 2 b filaments from poly-p-dioxa non existing fabric 2 was ironed hot under nitrogen at 120 ° C to give a composite fabric resulted.

This tissue 2 was applied in a width of 30 × 20 cm as shown in FIG. 2, at the end of the small pelvis opposite the abdominal cavity after the mesh had been fixed to the promoter, on the lateral pelvic wall and on the ventral abdominal wall.

Analogously, such flat structures can also be used Spleen, kidney and graft ruptures and also with Liver ruptures are used to supply the organs.  

If less elastic or flexible flat implan tate are required, the proportion of low melting zenden poly-p-dioxanone threads increased, resulting in a stronger strengthening of the network structure results.

Example 2

A mesh fabric was produced as in Example 1. This knitted fabric 2 shown in FIG. 3 was coated with finely chopped monofilaments of poly (lactide-co-glycolide) and poly-p-dioxanone in a mixing ratio of 3: 1 with an average thread length of 6 to 11 mm and under pressure 100 ° warmed. A felt-like flat implant was obtained, which was blood-tight and could be used successfully as a reinforcement strip for wound sutures, heart wall injuries and in vascular surgery.

Example 3

For the ablation of a saccular aneurysm of the aorta ascendens was as shown in Figures 4a and 4b procedure..:

After clamping the vessel with the forceps Z , the sack-shaped aneurysm A of the aorta was removed and the lumen was closed by a continuous mattress suture using a strip 6 of an implant according to the invention. A flat knitted fabric with a thread ratio of polyglactin to poly-p-dioxanone of 8: 1, which had a tensile strength of 200 N , was used for the strip.

In a parallel case, the lumen was closed by an oval-shaped flat fabric 2 as shown in FIG. 4b, which consisted of a flat composite fabric made of polyglactin and poly-p-dioxanone in a ratio of 10: 1, the former having a thread size of 60 dtex and the latter had a thread size of 66 dtex; the mesh world was 0.2 mm.

Example 4

In another case, seam reinforcement was carried out in the surgical area called pledget's from one Blended fabrics made in which the threads from the higher melting polyglactin in relation to the threads from the lower melting poly-p-dioxanone in one 5: 1 ratio, and all threads a titer of 40 dtex. This strip material with a Mesh size of 0.3 mm was also under nitrogen heat sealed at 120 ° C and could be processed excellently work.

Claims (6)

1. Flat implant made of resorbable material, characterized in that it consists of woven, knitted or knitted nets, strips or tapes, the filaments or fibers of which consist of at least two different ver resorbable materials with different melting points and different resorption, which after heating to a temperature which is above the melting point of the resorbable material with the lowest melting point and below the melting point of the other resorbable material with the highest melting point, have been deformed or pressed into a flat composite. 2. Implant according to claim 1, characterized in that the fibers or filaments from a lower melting poly-p-dioxanone and from a higher melting polyglactin in a mix ratio 1:15 exist. 3. Implant according to claim 1 to 2, characterized in that the mixing ratio of the fiber or filament from poly-p-dioxanone and polyglactin is about 1: 3.   4. Implant according to claim 3, characterized in that the pores or mesh sizes in the woven, knitted or knitted flat composite 0.1 to 4 mm. 5. Implant according to claim 1 to 4, characterized in that the filaments or fibers have a diameter of Have 10 to 200 dtex. 6. Implant according to claim 1 to 5, characterized in that the woven, knitted or knitted material or the sheet composite with a mixture from 1 to 20 mm long filaments or fibers from at least two different resorbable materia lien with woven, knitted or knitted under different melting points felt and heated at a temperature of 100 to 120 ° C and has been deformed.