Tissue repair device and molding process
Disclosed are medical articles and processes for forming the medical articles. The medical articles may take the form of a sponge having a three-dimensional shape comprising a reservoir. In an embodiment, the sponge is formed by placing a collagen slurry, optionally further comprising a mineral, in a mold and lyophilizing the slurry. In an embodiment, an improved molding process for such medical articles comprises forcing a slurry through a mold comprising the shape of a tube having an obstruction connected to the sidewall of the tube via an arm extending from the sidewall to the obstruction.
1 . A method of forming a medical article comprising an implantable sponge, the method comprising the steps of:
(a) providing a mold comprising:
(i) a tube comprising a first open end, a second open end, and a wall extending therebetween, and
(ii) an obstruction present in the second open end of the tube, wherein the obstruction is connected to the wall via at least two arms extending from the wall to the obstruction,
(b) providing a slurry comprising water,
(c) forcing the slurry through the tube from the first open end to the second open end and past the obstruction, thereby substantially filling the mold with slurry, and
(d) lyophilizing the slurry present in the mold, thereby forming an implantable sponge in the form of a three-dimensional shape comprising a reservoir capable of holding a liquid, the reservoir defined by a sidewall and a recessed surface, wherein the recessed surface comprises a shape complementary to a shape of the obstruction, wherein the sidewall comprises a plurality of cutouts extending from a top surface of the sidewall toward the recessed surface, wherein the plurality of cutouts extends through the width of the sidewall.
2 . The method according to claim 1 , wherein the slurry further comprises acid-soluble collagen, collagen fibers, and mineral particles.
3 . The method according to claim 1 , wherein the slurry further comprises a mineral and the slurry has a solids content of from 10 wt % to 40 wt %.
4 . The method according to claim 1 , wherein the mold comprises from two to eight arms.
5 . The method according to claim 1 , wherein the obstruction comprises a convex surface.
6 . A medical article formed by the method of claim 1 .
7 . The medical article according to claim 6 , wherein the implantable sponge comprises natural polymer fibers.
8 . The medical article according to claim 6 , wherein the implantable sponge further comprises a mineral and the mineral is present as particles having an average particle diameter of from 0.05 mm to 2 mm.
9 . The medical article according to claim 6 , wherein the implantable sponge comprises from 50 wt % to 95 wt % of mineral and from 5 wt % to 50 wt % of collagen, based on the total weight of the implantable sponge in its dry state.
10 . The medical article according to claim 6 , wherein the implantable sponge comprises acid-soluble collagen, collagen fibers, and mineral particles.
11 . The medical article according to claim 6 , wherein the implantable sponge comprises native collagen fibers having an average fiber length of from 0.5 mm to 10 mm.
12 . The medical article according to claim 6 , wherein the medical article is in the general shape of a cylinder, elliptical cylinder, or polyhedron.
13 . The medical article according to claim 6 , wherein the sidewall comprises from two to eight cutouts.
14 . The medical article according to claim 6 , wherein the sidewall comprises a cutout that extends from the top surface of the sidewall in the direction of the recessed surface but does not reach the recessed surface.
15 . The medical article according to claim 6 , wherein the cutouts have a cross-sectional shape of a square, rectangle, trapezoid, portion of an ellipse, or portion of a circle.
16 . The medical article according to claim 6 , wherein the top surface of the sidewall meets an exterior surface of the sidewall at an angle of approximately 90 degrees.
17 . The medical article according to claim 6 , wherein the top surface of the sidewall meets an interior surface of the sidewall at an angle of approximately 90 degrees.
18 . The medical article according to claim 6 , wherein the recessed surface is concave.
19 . The medical article according to claim 6 , wherein the medical article is a bone void filler or suitable for use in filling a defect in bone.