For centuries, the only way to whiten one's teeth was to either drink paint primer or leave teeth out in the desert for a few weeks and hope a roadrunner didn't steal them. Beautify chompers with a much faster and safer third option with today’s Groupon: for $39, you get a BleachBright Home Whitening System from BleachBright Canada online (a $289 value).

BleachBright Canada helps grins attain a snowy-white brilliance with safe and efficient home teeth-whitening kits that aim to provide long-lasting, natural-looking results. The Home Whitening System spiffs up insipid mouth tusks in merely 15 to 30 minutes with a soft moulding mouth tray that bonds with the contours of gums to create a snug whitening shell. Once the tray has been sculpted, all the coffee, lemon cake, and mandarin-scented markers that have scuffed each smile's veneer over time may evaporate with the help of two 10-millilitre syringes packed with potent carbamide peroxide gel. If used for seven days, the kit can help teeth achieve a 10-shade improvement or at least secure a spot in Zeus's personal choir.