3 Department of Restorative Dentistry, Federal
University of Para, Augusto Correa Street No. 1, Guama, Belem, Para, Brazil,
Phone: +559132521269 e-mail: cecymsilva@gmail.com.
Abstract
Aim: Evaluate in
situ the effect of nanohydroxyapatite paste (nano-HAP) before bleaching with
hydrogen peroxide 35% (HP35%) by ion chromatography (IC) Knoop hardness number
(KHN) and tristimulus colorimetry (TC).
목표: 나노 하이드록시아파타이트의 35%
과산화 수소 미백 후 효과에 대한 평가: 이온변화, 표면강도, 컬러
Materials and methods:
A total of 60 fragments were
obtained from third molars included (3 mm × 3 mm × 3 mm) and the specimens were
divided into three groups (n = 20): Gas chromatography (CG) (negative control
group) = no bleaching; HP35% (positive control group) = HP35% whitening
(whiteness HP35%); nano-HAP = application for 10 minutes before bleaching
treatment + HP35%. The specimens were fixed to the volunteers' molars. The KHN
and TC were measured before and after bleaching. For IC, the dentin layer was
removed, leaving the enamel that was crushed, and autoclaved for chemical
quantification (calcium, fluorine, and phosphorus). The results of KHN and TC
were analyzed statistically by analysis of variance (ANOVA) followed by Tukey
test (p < 0.05).
Results: The HP35%
group showed reduction of the Ca, F, and P ions. The initial and final KHN mean
of the CG and nano-HAP did not differ statistically; however, the group of
HP35% did differ statistically. The mean ΔE of the HP35% and nano-HAP groups
did not differ statistically from each other. However, they differed from the
CG.
Conclusion: The nano-HAP
paste preserved the KHN, promoted the lower loss of Ca and P ions and an
increase of F ions when compared with the CG, but did not influence the
effectiveness of the bleaching treatment.
나노 하이드록시아파타이트 페이스트는 치아미백 후 치면 표면강도를 보완하고 손실 된 칼슘과 인이온을 보충하며
미백치료의 효과에 영향을 주지 않는다.
Clinical significance:
Nano-HA is a biomaterial that has
shown positive results in the prevention of deleterious effects on the enamel
by the action of the office bleaching treatment.
Keywords: Dental enamel; Hydrogen peroxide; Hydroxyapatite
Tooth bleaching..