Breast implants, routinely in use today, characteristically have a life expectancy of up to 10-12 years. The fluid or gel implants currently in use have a tendency to leak', pervading neighboring tissue at a rate of approximately Icc per year. Whereas a breast implant may rupture or leak any time after surgery the incidental rate is approximately 5% at five years increasing dramatically as the implant ages achieving a rupture rate of nearly 70% by approximately 10 years. Since most recipients have two implants, the incidence of leakage or rupture is compounded for each recipient so that nearly one in four women may require additional surgery due to complications within five years of receiving implants and three out of four women may required additional surgery by 10 years. Implant rupture or leakage can be due to an injury or just normal wear-even the pressure of a mammogram can contribute to implant rupture. Plastic surgeons usually recommend the removal of a ruptured implant even if the silicone is still enclosed within the scar tissue capsule, because the silicone gel may eventually leak into surrounding tissue. Saline implants have been known to become infected and leak, often causing infection in surrounding tissues.

Aside from the known risks associated with surgery, the repeated corrective surgeries to improve or repair the damaged prosthesis may additionally result in an unsatisfactory cosmetic outcome.

From another angle, it is well known that the female breasts tend to"sag"with age (with or without a prosthetic implant). Prosthetic implants widely in use today, are relatively heavy and difficult for the breast skin and tissue to bear-causing the breast tissue to thin and shrink. After a relatively short period of time the breast begins to "sag", which in turn causes the skin to stretch, becoming thinner. The thinner the skin becomes the easier it becomes to physically and visibly discern the implant. Sometimes the skin shows evidence of'waves'particularly in saline solution implants, but also in silicone gel and sometimes in cohesive implants.

Another deficiency of conventional breast implants is that they are non-receptive to x-ray and ultra-sound mammary examination, periodical examinations recognized as essential to women's health. Silicone breast implants are known to be associated with calcium deposits in the breast. These calcium deposits can make it even more difficult to obtain a clear mammogram and can be mistaken for possible cancer (necessitating additional surgery or biopsy). Although the calcium deposits do not appear to be harmful, they can be indicative of a nearby cancer. Therefore, the presence of silicone implants may make it difficult to distinguish between the predictable effects of the implant and actual evidence of cancer.

It is, therefore, the general object of the invention to overcome these and other deficiencies common to conventional breast implants.

It is a further object of the present invention to provide a lighter breast implant, such that the breast can withstand the weight of the implant for a longer period of time, thereby prolonging the attractive cosmetic effect thereof.

It is a further object of the present invention to achieve a stable breast implant design that will not'wave'.

It is a further object of the present invention to prevent any kind of'leakage'and subsequent penetration of body tissues.

It is yet a further object of the invention that the breast implant will not interfere with x-ray and mammogram examinations.

SUMMARY OF THE INVENTION A prosthesis for physical implant, comprising an outer envelope and a filler of a yieldable non-liquid substance.

Preferably, the filler substance will consist of a fibrous material, e. g. cotton. The density of the fibrous material may be uniform, or may vary with respect to a different location.

Preferably the outer envelope will be of rough surface silicone.

BRIEF DESCRIPTION OF THE DRAWINGS: These and additional constructional features and advantages of the invention will become readily understood in the light of the ensuing description of a preferred

embodiment thereof, given by way of example only with reference to the accompanying drawings, wherein- Fig. 1 is a perspective view of a fiber filled breast implant prosthesis; Fig. 2 is a top view of the implant prosthesis of Fig. 1 ; Fig. 3 is a side view of the implant prosthesis of Fig. 1 ; and Fig. 4 is a schematic cross-section of the breast implant prosthesis of Fig. 1 ; DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS As shown in Figs. 1-3, the prosthesis generally designated A comprises an outer envelope B of rough surface silicone, which may be of the conventional type commonly used in prevailing prosthetic implants.

Unlike the conventional implants, the envelope B is filled with a fibrous material C, preferably of cotton or synthetic fibers such as Dacron, or Gortex (the latter two are currently widely used for surgical stitching procedures); however, any other fibrous material of similar character to those noted above may be employed.

The silicone envelope B is filled with the fiber content whereby the filling retains a uniform texture and density, with a flexible propensity to return to the conscripting shape of the encasing envelope.

The method employed for filling the envelope B is by encasing or"trapping"various sized fibers C or fiber aggregates. Envelope B is seamlessly and hermetically sealed to prevent direct contact with body tissue.

The solid'nature of the fiber implant provides a solution to the problem of leakage' penetrating surrounding tissue, a problem commonly associated with conventional breast implants, and will offer a greater'lifespan'thereby. diminishing the need for replacement surgery at irregular and close intervals.

The dense fibers also provide a solution to breast x-ray and mammogram examinations, since the cotton, Gortex", Dacron, and similar fibers are radiolucent.

The fiber filling has a specific gravity much lower than Igr/cm3 and will therefore virtually eliminate the problem of sagging'that plagues both the natural as well as the conventional saline water or other liquid substances filled implanted breasts. The unattractive'wavy'appearance will disappear in most if not all implants due to the especially light yet dense composition of the encased prostheses.

The fiber implants will retain a structural integrity and will provide strength and stability over significantly longer periods of time, precluding the necessity of repetitive cosmetic surgeries.

The fiber implant is virtually maintenance free and has the quality of reproducing a tactile response similar to breast tissue-providing additional attractive incentive for use as a preferred breast prosthesis for implant.

Fiber fillings also afford the unique ability to be prepared as layers with varying degrees of flexibility or firmness. This can be achieved by fusing or otherwise binding non-homogeneous layers of filling each comprised of loose, bulk, or aggregated fibers of differing strength, density, length, etc.-all with a view of achieving the optimal result for the individual patient.

Surgeons will be able to order tailored implants manufactured to order according to specifications such as exact dimensions, shape, size, flexibility, weight, and other parameters.

It has thus been established that the invention as herein disclosed, provides for an alternative to the prevailing composition of implants in general and breast implants, in particular. The solid/non-fluid components of the implant are lightweight, shaped, elastic, long lasting and do not interfere with x-ray and mammogram examinations.

It should be appreciated that the present invention is capable of being applied in the form of a variety of embodiments, only one of which has been illustrated and described above. The invention may be embodied in other forms without departing from its spirit or essential characteristics. The described embodiment is to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes, which come within the meaning and range of equivalency of the claims, are to be embraced within their scope.