If a product contains bleach (peroxide), it will whiten your teeth. But not all treatments are created equal. It's the concentration or percent of hydrogen peroxide a teeth-whitening system contains and the amount of time it's in contact with your teeth that determines its effectiveness.
Definition of fecund - producing or capable of producing an abundance of offspring or new growth; highly fertile Definition of fecund - producing or capable of producing an abundance of offspring or new growth; highly fertile
Verb. 1  To be unwilling to give or allow (someone something). [from 16th c.] 1608, Henrie Gosson, The Woefull and Lamentable wast and spoile done by a suddaine Fire in S. Edmonds-bury in Suffolke, on Munday the tenth of Aprill.