Yellow teeth indicate an addiction to smoking cigarettes, drinking coffee, or swishing with butter. I can't believe it's not toothpaste with today's Groupon: for $149, you get a BriteSmile in-office teeth-whitening treatment at Joseph A. Favia Dental Practice in Arlington Heights (a $500 value).

Dr. Joseph A. Favia and his skillful staff polish pearly whites to a high shine inside a modern 2,500-square-foot office. To kick off the two-hour BriteSmile treatment, the staff leads patients on a tour of the facility, then lets patients scrub their chompers clean with a brand-new toothbrush. Dr. Favia then checks for existing restorations before beginning the first of three 20-minute applications of BriteSmile gel, whose low concentration of hydrogen peroxide can whiten smiles more gently and permanently than wearing a set of fake Dracula fangs. Following the trio of plaque purges, patients brush teeth a second time to ensure their new shade has set. As clients depart with shiny new grins, the staff will advise them on post-treatment protocols such as avoiding foods that stain and refusing to let toddlers finger-paint their back molars.