A clinical trial was conducted with 25 subjects to evaluate the effects and safety of Zoom! Take-Home whitening gel, a 6% hydrogen peroxide gel for vital tooth bleaching. Tooth bleaching was accomplished using a tray system overnight for 6 nights. Over the 6 nights, a significant change (from darker to lighter) was seen in tooth shades as demonstrated by 3 assessment methods: VITA Shade Value Oriented Guide, Trubyte Bioform Color Ordered Shade Guide scoring system, and the Chroma Meter CR-321 assessments. VITA Shade scores showed a mean change of -6.49 shades (P = .0001) from baseline to day 4 and a -7.72 shades (P = .0001) from baseline to day 7. The Trubyte scores showed a mean change of -9.31 shades (P = .0001) from baseline to day 4 and a -10.77 shades (P = .0001) from baseline to day 7. The Chroma Meter was used to measure tooth color. Analysis of Chroma Meter data showed a significant change in color (delta E), 13.82 mean score change (P = .0001) from baseline to day 4 and a 7.25 mean score change (P = .0001) from baseline to day 7. At day 4 minor tooth sensitivity was reported, and all tooth sensitivity resolved within a few days after treatment.