Did not notice a change [SEP] I’m an orthodontic assistant I use my thumb/ thumb nail all day to engage wires into brackets. And I split my mail at least once a day. My nails have never been very strong and a coworker recommended using a polish to strengthen my nails. After a good amount of research and looking at tons of reviews I purchased this polish. It’s pretty expensive but I just wanted stronger nails. I would Clean my nails prior, adding polish every day and every 3 days taking the polish off completely and reapplying. I feel like I should of seen results by now. Sally Haden sells a polish for 3 dollar people I actually know have told me works great. So go try that!