Medical technology is advancing dramatically all the time, leading to numerous improvements in all fields, including dramatic advances in the appearance and function of prosthetics. However, we are not yet able to replace lost or deficient body parts with components that match the original, let alone achieve superhuman feats attributed to characters like DC Comic's Cyborg or Will Smith's character in I, Robot.
Replacement Lenses: Out of Focus
The human eye is a natural wonder. It is capable of adjusting itself to focus on near or distant objects simply by the power of your thought. As we age, though, the lens can change, losing this ability and ultimately becoming cloudy with cataracts. The only treatment is to remove the lens and replace it with an artificial one.
But replacement lenses don't work the same way that the natural lens does. Most often, a monofocal lens is used--one that just lets you see clearly at one distance, and then you have to wear glasses for everything else. More recently, multifocal lenses have been developed with different optic regions that let you see objects at multiple distances. The problem is some people can never adjust to looking through the different regions and these regions can create weird visual artifacts, especially at night. A jointed lens that can move forward and back with the muscle motion in your eye attempts to fulfill the role of your eye's natural lens. A review of studies suggests these don't actually give good benefits.
Dental Implants: Not the Whole Tooth
Dental implants are perhaps one of our closest achievements to reaching the natural standard, especially compared to dentures. Early denture manufacturers were so far off making true replacements that they often put actual teeth taken from dead people (or sometimes paying live people who were very poor) in dentures made out of wood or ivory. These were awkward and would slip out often. Plus they could spread disease.
Modern dental implants are much better. Because they are anchored in the jawbone like natural teeth, people can use them to eat most any food, and they can be cleaned just like natural teeth: brushed, flossed, and cleaned by a dentist twice a year. And they look great. In most cases, you can't tell if a person has a dental implant.
Unfortunately, they still don't live up to the standard of natural teeth. Dental implants don't last as long as natural teeth, not even as long as teeth that have been restored with a root canal.
Breast Implants: It's Complicated
Breast implants are a little different than the other two prosthetics we've been talking about because they're not intended to just replace something lost--they're supposed to improve on nature. And they don't, generally.
Although breast implants can reliably make breasts larger, they often fail in other aesthetic categories, such as the slope of the breast and the position of the areola/nipple complex. In a review contrasting natural breast appearance to surgical results, one plastic surgeon noted, "the line between enhancement and distortion is easily crossed."
And that doesn't even mention the topic of complications. Cosmetic breast augmentation is a procedure that results in numerous complications, including an up to 40% reoperation rate within ten years of the initial surgery for everything from improper sizing to breast implant rupture to painful hardening and deformation of the breast. And perhaps 15% of patients have reoperation within the first two years.
Students of Nature
As we continue to strive for prosthetics that can challenge Mother Nature in terms of appearance and function, we have a long way to go. We must remain humble and observe the lessons that she still has to teach us.
About The Author:
Dr. Matthew B. Candelaria (PhD, U of Kansas 2006) is a freelance writer who is very interested in the subjects of prosthetics and posthumanism. He has written thousands of articles on subjects in dentistry, ophthalmology, and plastic surgery as well as science fiction and criticism.
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