Effect of whitening gels formulated with sodium trimetaphosphate nanoparticles on color change, mechanical and morphological properties of tooth enamel

Author(s)

Amanda Scarpin Gruba

• Document type: Master's Dissertation
• Press: Araçatuba. 2023-05-02.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araçatuba
• Defense date: 2023-03-24
• Advisor: Alberto Carlos Botazzo Delbem

Abstract

This study evaluated in vitro the effects of calcium gluconate (CaGlu), sodium fluoride (F), sodium trimetaphosphate nano-sized (TMPnano), and F/TMPnano added to a 35% hydrogen peroxide (H2O2) bleaching gel on the color alteration, enamel mechanical and morphological properties, and trans-amelodentinal diffusion. Enamel discs / bovine dentin (n = 180) were divided according to the bleaching gel: 35% H2O2 (HP); 35% H2O2 + 0,1% NaF (HP/F); 35% H2O2 + 1% TMPnano (HP/TMPnano); 35% H2O2 + 0,1% NaF + 1% TMP nano (HP/F/TMPnano) e 35% H2O2 + 2% CaGlu (HP-Ca). The bleaching gels were applied three times (40 min/session) at 7-day intervals between each application. Then, color alteration (ΔEab and ΔE00), whitening index (ΔWID), surface hardness (SH), cross-sectional hardness (ΔKHN), surface roughness (Ra), and trans-amelodentinal diffusion were determined. The morphology and chemical composition of enamel were determined by Scanning Electron Microscopy (SEM) and X-ray Dispersive Energy (EDX). Data were submitted to ANOVA, followed by the Student-Newman-Keuls test (p <0.05). All bleaching gels showed significant color alterations after the bleaching procedure (p <0.001). ΔEab, ΔE00, and ΔWID were similar among the evaluated gels. Mineral loss (SH and ΔKHN), surface roughness, and transamelodentinal diffusion of hydrogen peroxide were lower for PH/F/TMPnano; the PH and HP Blue groups presented the highest values about the other groups (p <0.001). PH/F/TMPnano showed less morphological changes in enamel. It is possible to conclude that the addition of F/TMPnano to the in-office bleaching agent did not interfere with the bleaching efficacy and reduced enamel demineralization, surface roughness alteration, H2O2 diffusion and morphological changes. The association of F/TMPnano to the bleaching gel can be used as a new strategy to increase the safety of the product and with similar clinical performance. (AU)

• FAPESP's process: 21/04318-1 - Effect of bleaching gels formulated with sodium trimetaphosphate nano-sized on the color alteration, mechanical and morphological properties of dental enamel
• Grantee: Amanda Scarpin Gruba
• Support Opportunities: Scholarships in Brazil - Master