Reducing breast implant weight using chemically produced foam filling

Abstract

A method for manufacturing a breast implant including producing an elastic filler material including foam, by mixing a carbonate with a hydrolyzed silicone. A flexible shell, configured for implantation within a breast of a human subject, is filled with the elastic filler material.

Claims

1. A method for manufacturing a breast implant, the method comprising: producing an elastic filler material comprising foam, by mixing a carbonate with a hydrolyzed silicone; homogenizing the foam by spinning the foam during or after mixing the hydrolyzed silicone and the carbonate; and filling a flexible shell, configured for implantation within a breast of a human subject, with the elastic filler material.

2. The method according to claim 1, wherein mixing the carbonate comprises mixing sodium bicarbonate.

3. The method according to claim 1, wherein mixing the carbonate with the hydrolyzed silicone comprises mixing the hydrolyzed silicone and the carbonate with a catalyst.

4. The method according to claim 1, wherein producing the elastic filler material comprises producing a foam of silicone gel mixed with carbon dioxide bubbles.

5. The method according to claim 4, wherein producing the elastic filler material comprises tuning a hardness of the silicone gel by tuning at least one of a size and a density of the carbon dioxide bubbles.

6. A breast implant, comprising: an elastic filler material comprising a homogeneous foam of silicone gel mixed with carbon dioxide bubbles; and a flexible shell, which contains the elastic filler material and is configured for implantation within a breast of a human subject.

7. A method for manufacturing a breast implant, the method comprising: producing an elastic filler material comprising foam, by mixing a carbonate with a hydrolyzed silicone; producing the foam of silicone gel mixed with carbon dioxide bubbles; and filling a flexible shell, configured for implantation within a breast of a human subject, with the elastic filler material.

8. The method according to claim 7, wherein producing the elastic filler material comprises tuning a hardness of the silicone gel by tuning at least one of a size and a density of the carbon dioxide bubbles.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic sectional illustration of a human female breast with a breast implant, in accordance with an embodiment of the invention; and

(2) FIG. 2 is a flow chart that schematically illustrates a method for producing a foam filling for a breast implant, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Overview

(3) A breast implant may contain an elastic filler material, such as silicone gel, which is contained in a sealed flexible shell. A breast implant filled with such a material would be relatively heavy, and may cause discomfort to the wearer of the implant. To reduce the weight of the implant a gas such as air or carbon dioxide may be injected into the gel, to effectively form a foam and/or an emulsion. However, gas injection can be relatively complicated, and a simpler process would be useful.

(4) Embodiments of the present invention that are described hereinafter provide an implantable device that is used as a breast implant. In some embodiments, a foam filling of the implant is produced by chemical reactions. In the description hereinafter foam and/or emulsion are collectively referred to as foam, for brevity. For producing the foam, an embodiment the disclosed method uses the fact that the silicone gel is formed by hydrolysis of a silicone monomer, yielding hydrochloric acid (HCl) as a byproduct. A carbonate, such as sodium bicarbonate is added to the hydrolyzed mixture, and the carbonate reacts with the HCl to produce carbon dioxide bubbles (and common salt, NaCl). The mixture, with the bubbles may be spun to even out the bubbles in the gel.

(5) In an embodiment, the implant elasticity is tuned during production by tuning the hardness of the manufactured silicone gel, such that an implant made with the softest silicone gel would weight about 70 percent of that made with the hardest silicone gel. In an embodiment, tuning the hardness of silicone gel is performed by tuning the size and/or density of the gas bubbles created in the gel. The hardness of gel may be determined in the development stage of the gel preparation process, for example by trial and error, and kept the same by a stable manufacturing process.

(6) In some embodiments, an implant is provided, that by using a chemical process to produce the bubbles, comprises a highly homogeneous silicone gel.

(7) The disclosed technique can simplify the formation of light breast implants, for example by eliminating manufacturing steps such as gas injection and sealing steps. Furthermore, the disclosed technique may simplify the manufacturing process of the silicone gel itself, for example, by avoiding additional processes such as the rinsing out the HCl byproduct. Thus, implementing the disclosed technique may increase the availability of light breast implants.

System Description

(8) FIG. 1 is a schematic sectional illustration of a human female breast 20 with a breast implant 21, in accordance with an embodiment of the present invention. Implant 21 comprises a shell 22 filled with a light weight foam 23, whereas the preparation of foam 23 is described in more detail below. In the disclosed embodiment, breast implant 21 is positioned as a subglandular implant between breast tissue 24 and a pectoralis major muscle 26. In alternative embodiments, breast implant 21 may be positioned either as a subfascial, subpectoral, or submuscular implant, referring to different positions of the implant relative to pectoralis major muscle 26, as will be understood by those skilled in the art. The example shown in FIG. 1 is chosen thus purely for the sake of conceptual clarity. Embodiments of the present invention may apply to any design of breast implant that contains a foam.

Reducing Breast Implant Weight Using Chemically Produced Foam Filling

(9) FIG. 2 is a flow chart that schematically illustrates a method for producing foam filling 23, in accordance with an embodiment of the present invention. During part of the production stages of silicone gel, the hydrolyzed silicone contains hydrochloric acid (HCl). In some embodiments, a hydrolyzed silicone mixture with HCl as a byproduct is provided, at a preparation step 30. During one of the production steps, a carbonate, such as sodium bicarbonate (NaHCO.sub.3) is added to the hydrolyzed mixture, in a carbonate addition step 32, and the carbonate reacts with the HCl to produce carbon dioxide bubbles (and common salt, NaCl):
NaHCO.sub.3+HCl.fwdarw.NaCl+H.sub.2O+CO.sub.2(g)

(10) In some embodiments a catalyst may be added to the mixture to speed up the production of the bubbles at step 32 and/or the speed of curing of the resulting silicone-gel.

(11) Finally, at a mixture homogenization step 34, the foam is put on a spinner which spins the mixture so as to even (i.e., homogenize) the spatial distribution of carbon dioxide bubbles in the foam.

(12) In some embodiments, a flexible shell is filled with the filling material produced using the method of FIG. 2, and the shell is then sealed to produce breast implant 21.

(13) The example flow chart shown in FIG. 2 is chosen purely for the sake of conceptual clarity. The quantities of chemicals and/or the conditions at which the chemical reaction produces the bubbles may vary, so as to tune the size and/or density of the chemically resulting gas bubbles in the gel, and the variation in size of bubbles.

(14) As noted above, other chemicals may be used for creating the foam, where sodium bicarbonate was presented by way of example. Other manufacturing steps may be included, such as filtration and temperature settings, which for clarity are not shown. The timing of manufacturing steps may vary. For example, spinning of mixture can begin during or before or after production step 32.

(15) Although the embodiments described herein mainly address breast implants, the methods and systems described herein can also be used in other applications, in which an implant comprising silicone-gel needs to be lightweight.

(16) It will thus be appreciated that the embodiments described above are cited by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and sub-combinations of the various features described hereinabove, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art. Documents incorporated by reference in the present patent application are to be considered an integral part of the application except that to the extent any terms are defined in these incorporated documents in a manner that conflicts with the definitions made explicitly or implicitly in the present specification, only the definitions in the present specification should be considered.