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Published on: January 11, 2013
Is a Single Preliminary Session of In-office Bleaching Beneficial for the Effectiveness of At-home Tooth Bleaching? A
Objectives:
To evaluate the effect of combining in-office with at-home bleaching procedures in terms of the time required to obtain satisfactory tooth color, final color changes, and tooth sensitivity (TS) reported by patients.
Methods And Materials:
Twenty-six patients enrolled in this study used 10% carbamide peroxide in a bleaching tray for 1 h/d until satisfactory tooth color was obtained. One-half of the participants underwent a preliminary session of in-office tooth bleaching with 35% hydrogen peroxide for 45 minutes. The time in days for the patients to obtain satisfactory tooth color by at-home bleaching procedures was recorded. The color change of the maxillary canines was assessed using the Vita Bleachedguide 3D Master scale and a spectrophotometer at 1 week and after the end of bleaching procedures. Participants' satisfaction with their smile was recorded using a visual analog scale, and TS was determined throughout the entire treatment. Data were analyzed by t-test, Mann-Whitney test, or Fisher exact test (α=0.05).
Results:
The combined protocol reduced (by an average of 3.7 days) the time required to obtain satisfactory tooth color but increased the risk and level of TS. No difference in the final tooth color change (around 5.0 shade guide units; ΔE=11.6-14.9), or the level of patients' satisfaction with their smile, was observed.
Conclusions:
A preliminary session of in-office bleaching reduced the time necessary to obtain satisfactory tooth color with at-home bleaching but increased the risk and level of TS.
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