A common question that arises when people say 'extended wear contact lenses' is: What are extended wear contact lenses and what are they useful for? Well, first of all, let's explain what contact lenses are. 'Contacts' as many people refer to them, are pieces of polymacon placed on the cornea of the eye. For years, they could not be worn overnight because they could damage a person's clear vision. But now, extended wear contact lenses entered the market to stay and allow sleeping with lenses.
Extended wear contact lenses allow more oxygen to pass through to the cornea. In this way, a clear vision can be kept while a person sleeps with lenses. Extended wear contact lenses are made of highly oxygen permeable hydrophilic ploymeric materials.