PN0266 - Painel Efetivo
Área: 5 - Dentística

Experimental agent containing different concentrations of TiF₄ combined with highly concentrated hydrogen peroxide
Lins RBE, Rosalen PL, Romario-Silva D, Martins LRM, Cavalli V
Faculdade de Odontologia - UNIVERSIDADE FEDERAL DE ALAGOAS
Conflito de interesse: Não há conflito de interesse

This study evaluated color, mineral content, morphology and cytotoxicity promoted by 35% hydrogen peroxide (HP) combined with experimental gels containing titanium tetrafluoride (TiF₄). Bovine enamel blocks were treated with (n=10): HP or HP combined with TiF₄-gels in different concentrations: 0.05g (HPT.05), 0.1g (HPT1), 0.2g (HPT2), 0.3g (HPT3) and 0.4g (HPT4). Bleaching was performed in 3x15-min applications in three sessions, with 72-h intervals. Color (digital spectrometer) and enamel microhardness (KHN) were evaluated 24 h after bleaching sessions. Color change (CIELAB-ΔE_ab, CIEDE-ΔE₀₀), whiteness index (ΔWI_D), enamel morphology (scanning electron microscopy) and composition (energy dispersive X-Ray spectroscopy) were evaluated. MTT assay determined the viability of Keratinocyte cells (HaCat) treated with the gels. Data were analyzed by one-way ANOVA (ΔE_ab, ΔE₀₀, ΔWI_D, cell viability) and LSD or two-way repeated measures ANOVA (L*, a*, b*, KHN) and Bonferroni tests (α=5%). Lightness (L*) increased, a* and b* decreased, but HP promoted the lowest b* values (p<0.05). HPT.05, HPT1, HPT2 displayed ΔWI_D and ΔE_ab similar to HP, but no differences in ΔE₀₀ were found among groups (p>0.05). HP, HPT.05, HPT1 promoted higher KHN (p<0.05), HPT.05 exhibited no morphology alterations, and Ti was detected on TiF₄-gel treated surfaces. HaCat cells were > 80% viable for 0.05 g TiF₄, but HP reduced the cell viability.
HPT0.5 promoted bleaching and maintained enamel microhardness, without changing morphology or promoting cytotoxicity effects to HaCat cells.
(Apoio: CAPES  N° 001)

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