Spray Method For Forming Shells For Prostheses

Abstract

Shells for mammary prostheses and other devices are created by spraying a silicone dispersion onto a mandrel. Several coats of dispersion are applied with an interval for evaporation of solvent from the dispersion between application of coats. The shells created are uniform in thickness and have a desirably defect-free surface.

1 . A method for creating a silicone shell, the method comprising:
 a) providing a mandrel suitably sized and shaped for forming a desired shell;   b) applying a coating silicone dispersion to the mandrel by spraying the silicon dispersion at low pressure to create a shell having a desired thickness;   c) at least partially curing the silicone shell; and   d) removing the silicone shell from the mandrel.   
   
   
       2 . A method for creating a silicone shell, the method comprising:
 a) providing a mandrel suitably sized and shaped for forming a desired shell;   b) applying a coating silicone dispersion to the mandrel by spraying the silicon dispersion at low pressure;   c) allowing evaporation of at least a portion of the solvent in the coating silicone dispersion;   d) repeating steps b) and c) until a silicone shell having a desired thickness is formed;   c) at least partially curing the silicone shell; and   d) removing the silicone shell from the mandrel.   
   
   
       3 . The method of  claim 1  wherein the silicone dispersion is sprayed onto the mandrel using a high volume low pressure spray device. 
   
   
       4 . The method of  claim 1  wherein the silicone dispersion is sprayed onto the mandrel using a rotary atomizer. 
   
   
       5 . The method of  claim 1  wherein the silicone dispersion is an HTV silicone dispersion. 
   
   
       6 . The method of  claim 1  wherein the silicone dispersion is an RTV silicone dispersion. 
   
   
       7 . The method of  claim 2  wherein at least two coats of dispersion are applied to the mandrel. 
   
   
       8 . The method of  claim 2  wherein at least three coats of dispersion are applied to the mandrel. 
   
   
       9 . The method of  claim 2  wherein at least four coats of dispersion are applied to the mandrel. 
   
   
       10 . The method of  claim 1  wherein at least five coats of dispersion are applied to the mandrel. 
   
   
       11 . The method of  claim 1  wherein the dispersion is sprayed by atomizing the dispersion using a flow of air below 20 psi. 
   
   
       12 . The method of  claim 1  wherein the dispersion is sprayed by atomizing the dispersion using a flow of air below 10 psi. 
   
   
       13 . The method of  claim 1  wherein the shell is 0.00±0.004″ thick. 
   
   
       14 . The method of  claim 1  wherein the shell is 0.012″±0.004″ thick. 
   
   
       15 . The method of  claim 1  wherein the shell is 0.014±0.004″ thick. 
   
   
       16 . The method of  claim 1  wherein the shell is  0 . 013 ″± 0 . 004 ″ thick. 
   
   
       17 . The method of  claim 1  further comprising applying a coat of silicone dispersion to a portion of the mandrel to create a partial coat of dispersion. 
   
   
       18 . The method of  claim 17  wherein the mandrel includes an anterior surface and a posterior surface that meet at a perimeter region. 
   
   
       19 . The method of  claim 18  wherein the partial coat of dispersion is applied to the perimeter region of the mandrel. 
   
   
       20 . The method of  claim 17  wherein the mandrel has at least one relatively planar region and at least on region that is curved. 
   
   
       21 . The method of  claim 20  wherein the partial coat of dispersion is applied to the at least one region that is curved. 
   
   
       22 . The method of  claim 20  wherein the mandrel has a first region having a first radius of curvature and a second region having a second smaller radius of curvature. 
   
   
       23 . The method of  claim 22  wherein the region having the partial coat of dispersion is applied to the region having a second, smaller radius of curvature. 
   
   
       24 . The method of  claim 17  wherein at least one partial coat of dispersion is applied to at least a first portion of the mandrel. 
   
   
       25 . The method of  claim 1  wherein the mandrel is appropriately sized and shaped for forming an implantable prosthesis. 
   
   
       26 . The method of  claim 25  wherein the mandrel is appropriately sized and shaped for forming an implantable mammary prosthesis. 
   
   
       27 . The method of  claim 1  wherein the mandrel is appropriately sized and shaped for forming a tissue expander. 
   
   
       28 . The method of  claim 1  wherein the mandrel is appropriately sized and shaped for forming a round body implant. 
   
   
       29 . The method of  claim 1  wherein the mandrel is appropriately sized and shaped for forming a crescent-shaped body implant. 
   
   
       30 . The method of  claim 1  wherein the mandrel is appropriately sized and shaped for forming an oval body implant. 
   
   
       31 . A shell for a tissue expander formed by the method of  claim 1 . 
   
   
       32 . A shell for an implantable prosthesis formed by the method of  claim 1 . 
   
   
       33 . A prosthesis formed by a method comprising:
 a) providing a mandrel that is appropriately sized and shaped for forming a body implant;   b) applying a coating silicone dispersion to the mandrel by spraying the silicon dispersion at low pressure;   c) allowing evaporation of at least a portion of the solvent in the coating silicone dispersion;   d) repeating steps b) and c) until a silicone shell having a desired thickness is formed;   e) at least partially curing the silicone shell;   f) removing the silicone shell from the mandrel; and   g) applying a seal to the shell.   
   
   
       34 . The prosthesis of  claim 33  wherein the shell is shaped and sized for use as a mammary prosthesis. 
   
   
       35 . A tissue expander formed by a method comprising:
 a) providing a mandrel that is appropriately sized and shaped for forming a body implant;   b) applying a coating silicone dispersion to the mandrel by spraying the silicon dispersion at low pressure;   c) allowing evaporation of at least a portion of the solvent in the coating silicone dispersion;   d) repeating steps b) and c) until a silicone shell having a desired thickness is formed;   e) at least partially curing the silicone shell;   f) removing the silicone shell from the mandrel;   g) providing the shell with a filling port; and   h) sealing the shell.   
   
   
       36 . The prosthesis of  claim 33  wherein the mandrel is appropriately sized and shaped for forming an implantable prosthesis. 
   
   
       37 . The prosthesis of  claim 33  wherein the mandrel is appropriately sized and shaped for forming an implantable mammary prosthesis. 
   
   
       38 . The prosthesis of  claim 33  wherein the mandrel is appropriately sized and shaped for forming a tissue expander. 
   
   
       39 . The prosthesis of  claim 33  wherein the mandrel is appropriately sized and shaped for forming a round body implant. 
   
   
       40 . The prosthesis of  claim 33  wherein the mandrel is appropriately sized and shaped for forming a crescent-shaped body implant. 
   
   
       41 . The prosthesis of  claim 33  wherein the mandrel is appropriately sized and shaped for forming an oval body implant. 
   
   
       42 . The prosthesis of  claim 33  wherein at least a portion of the external surface of the shell is textured. 
   
   
       43 . The tissue expander of  claim 34  wherein the shell is shaped and sized for use as a mammary tissue expander. 
   
   
       44 . The tissue expander of  claim 34  wherein at least a portion of the external surface of the shell is textured. 
   
   
       45 . The method of  claim 1  wherein the silicone dispersion contains 10% to 50% silicone solids. 
   
   
       46 . The method of  claim 1  wherein the silicone dispersion contains 20% to 40% silicone solids. 
   
   
       47 . The method of  claim 1  wherein the silicone dispersion contains 25% to 35% silicone solids. 
   
   
       48 . The method of  claim 1  wherein the dispersion contains 28% to 32% solids. 
   
   
       49 . The method of  claim 33  further comprising filling the prosthesis with a liquid. 
   
   
       50 . The method of  claim 33  further comprising filling the prosthesis with a gel. 
   
   
       51 . The method of  claim 33  further comprising filling the prosthesis with a saline solution. 
   
   
       52 . The method of  claim 33  further comprising filling the prosthesis with silicone filler.