All-barrier elastomeric gel-filled breast prosthesis

Abstract

An elastomeric gel-filled prosthetic implant having a shell made of a single gel barrier layer. The barrier layer is formed of a homogeneous silicone elastomer capable of sterically retarding permeation of the silicone gel through the shell and having a bleed rate that is less than about 40% of the bleed rate of current shells which use a sandwiched construction with an internal barrier layer. Further, the barrier layer shell is made of a material that exhibits a wet strength that is comparable to or greater than current shells. The silicone elastomer may be a polydimethyl siloxane, and the substituted chemical group is a diphenyl group with a minimum mole percent of at least 13%. The implant may be designed for breast reconstruction or augmentation such that the shell is accordingly shaped. The shell wall thickness is at least 0.254 mm (0.010 inches), and desirably about 0.456 mm (0.018 inches). The implant shell may be made by dip-forming, spray-forming, or rotational molding. The exterior may be smooth or textured.

1 . A method of making a silicone gel filled prosthetic implant, the method comprising the steps of:
 forming an envelope comprising a silicone elastomeric polymer having a polysiloxane backbone and having a minimum mole percent of about 10% of a pendant chemical group selected from the group consisting of a phenyl group, a trifluoropropyl group and mixtures thereof;   introducing a silicone gel precursor material into the envelope such that the material is in direct contact with and substantially saturates said polymeric layer;   curing the silicone gel precursor material to obtain a soft prosthetic implant having a silicone gel core.   
     
     
         2 . The method of  claim 1  wherein the silicone elastomeric polymer is polydimethyl siloxane having a mole percent of about 15% of a diphenyl group. 
     
     
         3 . The method of  claim 1  wherein the step of forming the envelope comprises rotationally molding the envelope. 
     
     
         4 . A product made by the process of:
 forming a dispersion of a silicone elastomer and a solvent;   coating a form with the dispersion;   allowing the solvent of the dispersion to evaporate to form a silicone elastomer film on the form;   removing the silicone elastomer film from the form;   saturating the silicone elastomer film with a silicone gel; and   curing the silicone gel saturating the silicone elastomer film to form a composite;   whereby the composite has the property of a higher tensile strength than a tensile strength of a substantially identical silicone elastomer film that is not saturated with silicone gel.   
     
     
         5 . The product of  claim 4  wherein the silicone elastomer dispersion is polydimethyl siloxane having a mole percent of at least about 10% of a diphenyl group. 
     
     
         6 . The product of  claim 4  wherein the silicone elastomer dispersion is polydimethyl siloxane having a mole percent of less than about 25% of a diphenyl group. 
     
     
         7 . The product of  claim 4  wherein the silicone elastomer dispersion is polydimethyl siloxane having a mole percent of about 15% of a diphenyl group.