That's a great question, the daily lenses don't have any surface treatments applied to them, which means that they will build deposits (gunk, proteins, lipids, etc.) on the lens. They are basically processed less becuase they are meant to be thrown out at the end of the day. Other lenses 2 week and monthly have been treated to provide better deposit resistance or are made of materials that provide better depost resitance than dailies. Depending on the person on their wear I have seen patients that wear a two week lens monthly and have next to no depsoits on the lens and I have also seen patients that wear those same two week lenses and have deposits the first day or two. We are all built differently and the wear time is really a great way of giving patients a good idea of when to get rid of their lenses, but I have often metioned to patients that if they are a casual wearer then 2 weeks or 14 days is a good timeline for a two week disposable, but never go beyond the two week period, because the additional proteins can and will effect your comfort and ultimately your ocular health.

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Harry Chilinguerian ABOC-AC NCLC-AC COA