PN0490 - Painel Aspirante
Área: 5 - Dentística

Apresentação: 09/09 (Quinta-feira) - Horário: 10h30 - 12h00 - Sala: 25

Performance of natural agents over time - DOPA, dopamine and phytic acid - regarding dentin bond strength and MMP enzyme inhibition
Ferretti MA, Rischka K, Abuna GF, Mainardi MCAJ, Pecorari VGA, Aguiar FHB
Odontologia Restauradora - FACULDADE DE ODONTOLOGIA DE PIRACICABA
Conflito de interesse: Não há conflito de interesse

PURPOSE: The effects of natural cross-linkers (DOPA, dopamine, and phytic acid) on dentin microtensile bond strength (µTBS) and MMP activity (MMPact) over time were evaluated. METHODS: Teeth were divided into 7 dentin treatment groups (n=10) for the µTBS test: phosphoric acid-etching (PhosA); phytic acid-etching (PhyA); PhosA + DOPA; PhosA + dopamine; PhyA + DOPA; PhyA + dopamine; and PhosA + chlorhexidine (positive control). Slices with 500 µm-thick were submitted to in situ zymography by confocal laser scanning microscopy. Both tests were performed at 24 hours and one year. Surface topography (ST) and failure mode were analyzed by scanning electron microscopy (SEM). Dentin µTBS and MMPact data were submitted to Tukey-Kramer and Dunnett's tests (α=0.05); failure mode was analyzed by the chi-square test; and ST was descriptively analyzed. RESULTS: Etching without DOPA or dopamine presented higher immediate µTBS regardless of etchant, while dopamine and DOPA showed the lowest values. PhosA + chlorhexidine was similar to PhosA + dopamine. At one year, PhosA showed the highest mean, while PhyA had a decrease in µTBS, similar to dopamine and PhosA + chlorhexidine; PhyA + DOPA was similar to PhyA + dopamine. Phosphoric acid presented the highest MMP activity at both evaluation times, while PhyA and PhosA + chlorhexidine presented the lowest. At one year, PhosA + DOPA had a significantly increase in its fluorescence for the MMP assay.
CONCLUSION: dopamine, DOPA, and phytic acid showed promising results in regard to their performance over time on dentin MMP activity.
(Apoio: CAPES  N° 001)

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PN0495 - Painel Aspirante
Área: 5 - Materiais Dentários

Apresentação: 09/09 (Quinta-feira) - Horário: 10h30 - 12h00 - Sala: 25

Efeito de uma solução fluoretada à base de nanopartículas de prata associada a um dentifrício com alto teor de flúor na erosão dentinária
Silva VFFME, Emidio AG, Zanin GT, Gonçalves MCC, Guiraldo RD, Lopes MB, Berger SB
Odontologia - UNIVERSIDADE NORTE DO PARANÁ
Conflito de interesse: Não há conflito de interesse

O objetivo deste estudo foi investigar a capacidade de uma solução fluoretada à base de nanoparticulas de prata (AgNano) associada ou não à um dentifrício com alta concentração de flúor (D) (5000 ppm F-) na erosão dentinária, 108 blocos de dentina foram obtidos a partir de incisivos bovinos. As amostras foram analisadas quanto à microdureza e rugosidade. Em seguida, divididas em 8 grupos: 1 - escovação com água destilada (H2O); 2 - escovação com D; 3 - tratamento com AgNano + D; 4 - AgNano + H2O; 5 - tratamento com diamino fluoreto de prata (DFP) + D; 6 - DFP + H2O; 7 - verniz fluoretado (VF) + D, 8 - VF + H2O. Todas as amotras foram submetidas ao desafio erosivo com ácido cítrico a 0,3% (pH 2,6) e escovação com o D ou H2O por 5 dias. Após os tratamentos e desafio erosivo, a rugosidade foi novamente avaliada. Em todos os grupos houve perda de estrutura dental avaliada pelo aumento de rugosidade, entretanto, os grupos tratados com VF apresentaram a menor perda de estrutura dental comparada aos demais grupos.
Concluiu-se que, somente o VF foi capaz de inibir a erosão dental e o uso de um dentífricio com alta concentração de flúor não foi capaz de minimizar a erosão.
(Apoio: CAPES  N° 001)

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PN0489 - Painel Efetivo
Área: 5 - Dentística

Apresentação: 11/09 (Sábado) - Horário: 14h00 - 15h30 - Sala: 21

Evaluation of different storage solutions on the bleaching efficacy of an experimental agent with 35% hydrogen peroxide
Lins RBE, Guimarães LMG, Coelho CSS, Rosalen PL, Cavalli V
Faculdade de Odontologia - UNIVERSIDADE FEDERAL DE ALAGOAS
Conflito de interesse: Não há conflito de interesse

Evaluated the influence of storage solutions on color evaluation, mineral content, morphology and composition of the enamel submitted to dental bleaching with 35% hydrogen peroxide (HP) or HP associated to an experimental gel based on 4% titanium tetrafluoride (T). Enamel blocks were treated with (n=10): commercial HP-artificial saliva (PH-AS); HPT immersed in: AS (HPT-AS); distilled water (HPT-DA); buffered solution (HPT-BS); human saliva (HPT-HS); AS (without bleaching). Bleaching was performed in 4 sessions (3x15min) with 72-h interval. Color change, mineral content, morphology and composition were analyzed by spectrophotometer (∆L, ∆a, ∆b, ∆E_ab, ∆WI_D, ∆E₀₀), Knoop microhardness (KHN), scanning electon microscopy (SEM) and energy dispersive spectrometry (EDS), respectively. Data were analyzed by one-way ANOVA and Tukey (color), and two-way repeated measures ANOVA with Bonferroni (KHN) tests (α=5%). SEM and EDS were submitted to descriptive analyzes. HP, HPT-AS and HPT-DW did not differ, which presented higher values of ΔL, ΔE_ab, ΔWI_D and ΔE_oo and lower of Δb. HPT-BS and HPT-HS presented lower ΔL, ΔE_ab, ΔWI_D and ΔE_oo and higher of Δb. No difference in Δa was observed among groups and there were no changes in the color parameters for AS. KHN increased for HPT-HS, presenting higher KHN than HP-AS, HPT-BS and AS. HPT-BS decreased KHN and promoted morphological changes. Experimental groups presented low concentration of Ti.
Storage solution allowed the bleaching, however, only AS, DW and HS maintained the mineral content, enamel morphology and composition.
(Apoio: CAPES  N° 001)

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