Implantable device having a random orientation of a non-absorbable filament
An implantable structure, method for making the structure and method for using the structure, where the structure includes a combination of non-absorbable and absorbable components, and the implantable structure has a randomly uniform array of materials. The resulting implantable structure provides improved tissue ingrowth and flexibility after implantation and after absorption of the absorbable materials.
1. An implantable device having a random orientation of a non-absorbable filament, formed by the method comprising the steps of:
a. obtaining at least a first non-absorbable filament and a first absorbable filament, wherein said first absorbable filament has a lower melting point than said first non-absorbable filament;
b. kinking at least one of said first absorbable filament and said first non-absorbable filament;
Forming a first yarn and a second yarn, wherein at least one of said first yarn and second yarns includes a first non-absorbable filament and at least one of said first yarn and second yarns includes a first absorbable filament, and wherein said kinked filament is used in forming either said first yarn or said second yarn
b. Forming an initial woven structure comprising said first yarn and second yarn;
c. Subjecting said initial woven structure to a first heat treatment at a first temperature sufficient to cause shrinkage of said first absorbable filament, and thus buckling at least the second yarn and forming an initial heated structure;
d. heating said initial heated structure to a second temperature, said second temperature being higher than said first temperature, wherein at least a portion of said first absorbable filament is melted; and
e. Allowing said heated structure to cool to form a resulting implantable device.
2. The implantable device of claim 1 , further comprising the step of compressing said initial woven structure during said step of heating said initial heated structure at a second temperature.
3. The implantable device of claim 1 , wherein said first yarn comprises a first non-absorbable filament and a first absorbable filament, and said second yarn comprises a second non-absorbable filament and a second absorbable filament.
4. The implantable device of claim 3 , wherein said first absorbable filament is polydioxanone and said first non-absorbable filament is polypropylene.
5. The implantable device of claim 1 , wherein said first yarn comprises a first non-absorbable filament, a first absorbable filament and a second absorbable filament, and said second yarn comprises a second non-absorbable filament and a third absorbable filament.
6. The implantable device of claim 5 , wherein said first absorbable filament is polyglactin, said second absorbable filament is polydioxanone, and said first non-absorbable filament is polypropylene.
7. The implantable device of claim 1 , wherein said resulting implantable device has a thickness of about 0.1-2 mm after said step of cooling.
8. The implantable device of claim 1 , wherein said step of subjecting said initial woven structure to a first heat treatment comprises placing said initial woven structure in a heating source having a gap that is at least as wide as said thickness of said initial woven structure.
9. The implantable device of claim 1 , wherein said step of subjecting said initial woven structure to a first heat treatment comprises subjecting said initial woven structure to a first temperature that is about 0.1 to about 2° C. less than the melting point of the absorbable filament having the lowest melting point in said initial woven structure.
10. The implantable device of claim 1 , wherein said second temperature is a temperature that is about 0.1° C. to about 20° C. greater than the melting point of the absorbable filament having the lowest melting point in said initial woven structure.