Bausch & Lomb were the first to use this material for contacts, and introduced the first soft contacts to the market in 1971. The material was perfect because it allowed oxygen and carbon dioxide to easily pass through, essential for a healthy cornea. HEMA also absorbed water; in fact 38 percent of the material was water. This made the contact lense much more comfortable than the previous plastic hard lenses.
In the 1960's, a chemist from Europe named Dr. Otto Wichterle developed a revolutionary type of plastic called hydroxyethylmethacrylate (HEMA) that he was originally intending to use as artificial blood vessels. It was discovered this material was perfect for contact lenses, and it changed the contact lense industry forever.
However, soft contact lenses have their drawbacks. For one, vision is not as clear as with hard lenses. Also, besides absorbing water, these lenses tend to absorb infection-causing bacteria along with it, requiring a rigorous cleaning process to disinfect them. These types of lenses are easier to tear or rip during cleaning/insertion, and generally only last a year or two before a replacement is needed.
Thankfully, new disinfection saline solutions have been developed that make the cleaning and sterilization process much easier.
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Contact Lenses: Soft, For Daily Wear