What is the most common material used for soft contact lenses?

The most common material used for soft contact lenses is hydrogel. Hydrogel materials are characterized by their ability to absorb water, which allows them to maintain moisture and provide comfort to the wearer. This material has been widely used since the introduction of soft contact lenses in the 1960s due to its flexibility, softness, and excellent compatibility with the human eye.

Hydrogels make it easier for oxygen to pass through to the cornea, although they are less permeable compared to silicone hydrogel materials. They typically provide adequate comfort for daily wear, which is a significant reason for their popularity. The combination of moisture retention and softness contributes to an overall positive experience for those who wear soft contact lenses.

While silicone hydrogel is becoming increasingly common due to its superior oxygen permeability, hydrogel remains the foundational material used in many soft lenses available on the market today. It is important to note that options like PMMA (polymethyl methacrylate) and RGP (rigid gas permeable) are primarily used for different types of lenses that serve specific purposes and user needs, thus they are not considered the most common in the context of soft contact lenses.