Clinical evaluation of the efficacy of 10% carbamide peroxide bleaching agent used during night-time and day-time

Abstract EN

This split-arch clinical study was performed to compare the effects of using 10% carbamide peroxide bleaching agent for one hour twice a day with its use for 8 hours/night on tooth color change, color stability and sensitivity.

Method: Bleaching trays, with reservoirs for the six maxillary anterior teeth, were fabricated for 12 volunteers.

The trays were cut into two halves between the left and right central incisors (day-side vs.

night-side) to be used with 10% carbamide peroxide for two weeks.

The day-side tray was applied for one hour twice a day, while the night-side was applied for 8 hours overnight.

Objective color measurements, using a colorimeter, were adopted to measure the color of the teeth of the two sides at the baseline appointment and at 1, 2, 3, 6 and 12 weeks.

Total color difference (ΔE*) between two color measurements was calculated for all periods.

Teeth and soft-tissue sensitivity were self-recorded for both sides during the bleaching weeks and the following week.

Both Student's t-test and Tukey's test were used to compare ΔE* between the two sides and with time at p<0.05.

Results: Both sides showed significant differences in ΔE* over time (p<0.05).

However, no significant differences were recorded between the two sides at each measuring period (p>0.05).

Conclusion: At-home bleaching treatment using 10% carbamide peroxide for one hour twice daily produced similar tooth color change, stability and sensitivity with its use for 8 hours/night.