Silicone hydrogel lenses
Silicone hydrogel contact lenses are contacts made of silcone hydrogel which is an oil based material, in contrast to regular water based material. They can be used either as regular monthly replacements or as continuous wear replacements, depending on your optician's recommendation.As the material allows more oxygen to the eye and the cornea, these lenses are sometimes recommended as continuous wear lenses, in which case your optician would recommend how long to keep them in consecutively which can vary, normally from a few days up to a month. Silicone based lenses can also be recommended to use only during the day and to be removed while sleeping.
Silicone hydrogel lenses are not suitable for everyone. In general, the dryer the eye, the dryer the lens. So for dry eyes, silicone hydrogel lenses are likely a better match than moister lenses such as most daily replacements, as silicone based lenses contain less water overall.
For continuous wear, no cleaning is usually required since you leave the lenses in overnight. When you use silicone hydrogel contacts as monthly replacements however, cleaning is required. To clean silicone hydrogel lenses, there are certain solutions that specifically mention being designed to suit especially silicone hydrogel lenses (for example Opti-Free Replenish and Complete Revitalens).
