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Tooth bleaching with hydrogen peroxide and nano-hydroxyapatite: a 9-month follow-up randomized clinical trial
M Vano1, G Derchi1,2, A Barone1,2
1Department of Surgical Pathology, Medicine, Molecular and Critical Area, University of Pisa, Pisa, Italy.
Objectives:
The aim of this study was to compare the amount of tooth colour change, rebound rate and tooth sensitivity in patients submitted to a bleaching technique with 6% hydrogen peroxide (HP) with or without 2% nano-hydroxyapatite (n-HA).
Methods:
Sixty subjects were included in this examiner-blinded, randomized clinical trial using a 6% HP gel with or without 2% n-HA. Tooth colour and tooth sensitivity were analysed before and after treatment. All data were analysed statistically.
Results:
After bleaching, both treatments demonstrated significant improvements in tooth shade (P < 0.05 for both groups). At the 9-month recall, tooth shade remained significantly lighter than at baseline (P < 0.05 for both groups). However, a relapse of the tooth shade was observed compared with the immediate post-bleaching result (P < 0.05). 6% HP with 2% n-HA produced significantly lower sensitivity (P < 0.05) than the bleaching product without n-HA. Colour change evaluation resulted in no difference between the two groups.
Conclusion:
Both treatments demonstrated significant improvements in tooth shade. The bleaching effectiveness of the tested products was comparable. The use of 6% HP with 2% n-HA reduced the incidence of sensitivity during the bleaching treatment compared to a bleaching agent that did not contain n-HA.
