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A clinical study assessing the short-term efficacy of combined in-office/at-home whitening treatment
Dubravka Knezović Zlatarić1, Maja Žagar1, Davor Illeš1
1Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia.
Objective:
The purpose of this randomized clinical trial was to assess the efficacy of color change in combined in-office/at-home whitening.
Materials And Methods:
Thirty participants were randomly divided into two groups: 15 received combined treatment in-office whitening (6% hydrogen peroxide + 2 weeks at-home whitening with 16% carbamide peroxide [CP]); 15 were assigned to control group. Instrumental color measurements were obtained before whitening (t0 ), immediately after in-office whitening (tin-office ), after 1 week of active treatments (t1 ), and at the completion of the whitening treatment (t2 ). CIE L*a*b* values were recorded and CIE L*a*b* and CIEDE2000 color differences were calculated.
Results:
The color change at tin-office was ΔEab = 4.7 and ΔE00 = 3.2 and overall color change of combined method at t2 was ΔEab = 8.2 and ΔE00 = 5.3 (P < 0.05). A statistically significant effect for the mean CIE L*a*b* and CIEDE2000 values was detected within time with the mean a*, b* and C' values decreasing and mean h' values increasing significantly (P < 0.05).
Conclusions:
Combined in-office/at-home whitening was effective. Whitening efficacy increased upon application of 16% CP in combined in-office/at-home treatment (P < 0.05).
Clinical Significance:
The statistically significant increase in color change recommends clinical application of combined in-office/at-home whitening treatment.
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