Carving Custom Implants
If
I were to ask you what comes to mind when I say “implants in plastic surgery”
you would immediately think of breast implants. Breast implants are by far the
most common type of silicone implant plastic surgeons place.* In 2016
there were almost 300,000 breast augmentations with implants. Chin implants
were in distant second with under 17,000 patients, and there are many other
types of implants as well. Chin and breast implants can be mass produced, but
others must be custom made.
Custom
implants can be created through several different methods. A moulage, or mold
can be made of the area to be augmented.
This mold is then used to cast the silicone implant. A more recent
method utilizes advancements in both imaging and 3D printing. Computed
tomography (CT) scan is taken of the area and a virtual 3D model is created.
This 3D model can then be virtually augmented to obtain the desired appearance.
Once the augmentation is determined, a mold is printed. Similar to the moulage,
the mold is then used to create the silicone implant.
With
both methods, imperfections are to be expected. Implants function similar to
the body’s bony framework. They provide a solid structure for which the soft
tissue drapes over. How the soft tissue lies over the implant is where
imperfections can occur. Even with the best cast implant, variations in a
person’s skin, muscle, or fat can cause the same implant to appear different.
To
adjust for variations in a patient’s soft tissue, the implant must be further customized
intra-operatively. The implant is placed in position and the aesthetics are
evaluated. It is then removed and carefully carved to achieve the right
appearance. This is when the plastic surgeon employs his artistic talent. The
surgeon must be able to decipher how each curve and angle influences the
appearance and imagine what changes will produce the desired outcome. Sometimes
this can be a few delicate passes of the scalpel. Others though, such as in the
image shown, may require a more extensive trimming. In this picture, the chest
wall implant for a patient with pectus excavatum created too much projection. I can be seen thinning the implant to
create a smoother transition from the chest to abdomen.
No
matter what the defect is, if an implant is the right choice then a skilled plastic
surgeon can create the right implant to achieve the desired outcome.
*
I say silicone because technically suture, or stitches, are the most common
type of implant we place as surgeons.
