Efffect of a resinous infiltrant on the tratment of white spot lesions: in vitro and in situ analysis

Author(s)

Maria Cristina Carvalho de Almendra Freitas

• Document type: Doctoral Thesis
• Press: Bauru.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia de Bauru (FOB/SDB)
• Defense date: 2015-04-10

Examining board members

Linda Wang; Roberta Caroline Bruschi Alonso; Ticiane Cestari Fagundes; Maria Fidela de Lima Navarro; Anuradha Prakki

• Advisor: Linda Wang; Maria Fidela de Lima Navarro

Abstract

Among the strategies for early caries lesions treatment as active white spot, the resin infiltrant has been employed filling the enamel pores and preventing their progression. The aim of this study was to evaluate the effect of caries infiltrant (Icon®) on artificial carious lesions produced by different protocols, and the efficiency of this treatment after new challenge acid by in vitro and in situ experimental models, using the surface microhardness (SH) and cross-sectional microhardness (CSH). In the in vitro phase, artificial carious lesions were performed on 45 enamel bovine specimens (6x4mm) by three different protocols (DE-RE cycling, MC gel and MHDP solution). The specimens were treated with the infiltrant and subjected to a new challenge by DE-RE cycling. This design resulted in four conditions at the same specimen: sound (S), after demineralization (D), after the treatment with infiltrant (I) and after the new acid challenge (N). In the in situ phase, 15 volunteers wore intraoral appliances containing two specimens for 14 days, inducing the lesion formation by sucrose solution dripping 8x/day. In both models, SH and CSH were evaluated in all conditions of the specimens up to 220&#x3BC;m. Data were collected and processed as percentage from the difference to each condition compared to sound stage to be statistically analyzed with ANOVA (repeated measures) and Tukey test (p <0.05). For all tested conditions, demineralization protocols were able to produce subsurface carious lesions. All in vitro protocols promoted hardness loss higher than 75% while in situ protocol promoted almost 40%. There is a reduction in the hardness loss as the depth increases, in which the main differences can be noticed up to 50&#x3BC;m. The infiltrant evaluated in all conditions was able to partially re-balance the internal hardness, however its strength and effect after the new challenge acid had been limited. (AU)

• FAPESP's process: 12/18579-2 - Effect of a resin infiltrant on white spot lesions treatment: in vitro, in situ and in vivo analyses
• Grantee: Maria Cristina Carvalho de Almendra Freitas
• Support Opportunities: Scholarships in Brazil - Doctorate