Is the over the counter teeth whitener a waste of money

yes they do work... anything as far as whiting toothpaste works... I find it better to stay away from "the unheard of brands"... The only problems are: over time the tooth paste begins to weaken the enamel on your teeth ( I know this from experience)... It can become hard and painful to chew things such as chips... If you DO NOT stop the coffee the effects will not last long. It would be like cleaning dirt off of a table just to put new dirt back on... The thing with coffee is it has mad you unhappy with your smile.... Get made!!!! GRRRR