”Objective:” The purpose of this randomized, single-bind, clinical study was to evaluate the amount of time necessary for at-home whitening (HW) to match the result of one in-office whitening (OW) treatment using two shade guides. “Methods:” Twenty patients participated in this study. The degree of color change was measured subjectively using the VITA Bleachedguide 3D Master (BSG, Vita Zahnfabrik,) and Vitapan Classical shade guide (CSG, Vita Zahnfabrik,), and objectively using the Vita Easyshade intraoral spectrophotometer (ES, Vident). The total color difference was calculated using the formula: Delta E*ab = [(Delta L*)2+(Delta a*ab)2+(Delta b*ab)2]1/2 . The whitening treatments were randomly applied to the right or left maxillary anterior teeth on the same patient, in-office for sixty minutes with 25% hydrogen peroxide (Zoom gel, Discus Dental), or for 5 days at-home overnight with 10% carbamide peroxide (Nite White Excel, Discus Dental) . The tooth color was evaluated at baseline, one day after OW treatment, 6 days (5 days after HW treatment) and at 20 days (14 days after HW and 19 days OW). The results were analyzed by two way ANOVA/Tukey's t-test (p≤0.05). “Results:”
Time | Treatment | Delta E* | Delta CSG | Delta BSG |
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6 days | HW | 5.2 | 3.8 | 3.7 |
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6 days | OW | 6.6 | 3.7 | 3.7 |
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20 days | HW | 6.21 | 3.4 | 3.4 |
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20 days | OW | 6.59 | 3.3 | 3.3 |
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“Conclusion:” While there was a subtle difference in Delta E* between OW and HW at 6 days, the measurement of Delta E* and the two shade guides agreed that 5 days of home whitening with 10% carbamide peroxide (8hrs/day) produced the same result as one in-office treatment with 25% hydrogen peroxide (1h). Funded in part by Vita Zahnfabrik, Bad Sackingen, Germany.