ABSTRACT
ABSTRACT Objective To compare the capacity of silver diamine fluoride (30%) and the bioactive giomer light-curing varnish for arresting ICDAS score 5 non-retentive caries lesions. Material and Methods An in vitro analytical study was conducted using 36 healthy primary teeth, in which a cavity was created, divided into 3 groups: control (distilled and deionized water), giomer-based light-curing varnish - Barrier Coat, and Silver Diamine Fluoride 30% - Cariestop (SDF). The samples were analyzed for mineral loss as measured by surface microhardness (SMH).The Knoop microhardness test was performed using the HVS-1000 microhardness tester. The data were compared by two-way analysis of variance - treatment and time (before and after treatment) followed by Tukey's post-test. The significance level adopted in all analyzes was 5%. Results The specimens treated with giomer showed higher SMH compared to the untreated group but were similar to those of the SDF group. The SDF group, on the other hand, showed no statistically significant difference from the control group (p=0.010). Conclusion The giomer varnish had a remineralizing effect on artificial dentinal caries.
Subject(s)
Tooth, Deciduous , In Vitro Techniques , Diamines , Hardness Tests/instrumentation , Analysis of Variance , Statistics, Nonparametric , Dental CariesABSTRACT
Abstract Objective: To evaluate the effect of immersion and acid challenge with cola drink on color change (ΔE), Vickers hardness (VHN) and surface roughness (Ra) of artificial acrylic resin teeth. Material and Methods: The artificial teeth were divided into 6 groups (n= 8): TC (Trilux/Control), BC (Biotone/Control), TAC (Trilux/Acid challenge), BAC (Biotone/Acid challenge), TI (Trilux/Immersion) and BI (Biotone/Immersion). The teeth were embedded in acrylic resin and the labial side was serially polished to provide appropriate flat surface. The samples of TC, BC, TI, BI groups were immersed in artificial saliva and cola drink (coke) for 7 days, respectively. The acid challenge was performed with immersion of samples in coke for 5 min, and subsequently immersion in artificial saliva for 2h. This cycle was repeated at 4 times/day, during 7 days. The tests of VHN, ΔE and Ra were analyzed before and after the challenge and immersion groups. Data was analyzed by ANOVA, Tukey and T test (α = 0.05). Results: There was no difference in Ra values between groups after treatments. However, there was a decrease in VHN for all groups. BI (19.2 ± 0.3) presented significantly lower hardness than BAC (19.5 ± 0.9) and BC (20.2 ± 0.5). Groups BI (2.18 ± 0.41) and TI (1.50 ± 0.43) had statistically higher ΔE compared to the other groups. Conclusion: The hardness of resin teeth decreased after acid challenges, but the roughness surface was not affected. The color was more affected by the times of exposure in cola beverage and remineralization in artificial saliva, which were associated to the material degradation (AU).
Subject(s)
Tooth, Artificial , Acrylic Resins/chemistry , In Vitro Techniques/methods , Dental Prosthesis , Beverages , Brazil , Analysis of Variance , Cola/chemistry , Hardness Tests/instrumentationABSTRACT
Objetivo: Avaliar a influência de diferentes espátulas e superfícies de manipulação na dureza Knoop de cimentos ionoméricos nacionais: Vitro Molar® (VTM) e Maxxion R®(MXR) e importado: Ketac MolarTMEasymix (KTX). Método: Para cada condição, corpos de prova ionoméricos com 7mm de diâmetro e 0,5mm de altura foram confeccionados e colocados em moldes de PVC para confecção de blocos resinados para posterior leitura em Microdurômetro. Condições experimentais utilizadas: C-I: espátula de plástico + placa de vidro; C-II: espátula de metal + placa de vidro; C-III: espátula de plástico + bloco de papel; C-IV: espátula de metal + bloco de papel. Cada amostra sofreu cinco indentações com carga de 25g por 5s após 24 horas e 30 dias. Os resultados obtidos foram avaliados e submetidos aos testes de Análise de Variância para dados repetidos e teste complementar de Tukey (5%). Resultados: Os valores de microdureza de todos os cimentos ionoméricos aumentaram após 30 dias. O cimento VTM foi o mais sensível quando se alteravam as condições experimentais de manipulação. A condição I foi a que apresentou os maiores resultados de microdureza após 24 horas para o VTM (medias e desvio-padrão): 29,6 (5,0) e KTX: 46,1 (9,4), o MXR: 46,2 (12,3) obteve melhor resultado nesse mesmo período com a condição IV. Após 30 dias, a primeira condição (espátula de plástico + placa de vidro) continuou com os maiores valores de dureza para, VTM: 113,6 (17,7), MXR: 82,4 (13,4), já para o cimento KTX, a condição IV apresentou o maior valor de dureza: 71,3 (17,6). Conclusão: Após 30 dias, as diferentes condições de manipulação utilizadas interferem no resultado final de microdureza dos cimentos VTM e MXR. O material KTX sofre menor influência das condições de manipulação...
Objective: To evaluate the influence of different types of spatulas and manipulation surfaces on the Knoop hardness of the Brazilian glass ionomer cements Vitro Molar® (VTM) and Maxxion R® (MXR) and the imported Ketac MolarTM Easymix (KTX).Method: For each experimental condition, glass ionomer cements samples (7 mm diameter and 0.5 mm high) were fabricated and inserted in PVC molds to produce blocks for the microhardness reading. The experimental conditions were: C-I: plastic spatula + glass plate; C-II: metal spatula + glass plate; C-III: plastic spatula + paper mixing pad; C-IV: metal spatula + paper mixing pad. Each sample received five indentations with a 25 g load for 5 s after 24 h and 30 days of fabrication. The obtained results were analyzed by repeated measures analysis of variance and Tukey?s test at 5% significance level. Results: Microhardness of all glass ionomer cements increased after 30 days. The VTM cement was the most affected by the different manipulation conditions. After 24 h, VTM [29.6 (5.0)] and KTX [46.1 (9.4)] presented the highest microhardness values with C-I and MXR [46.2 (12.3)] presented the best result with C-IV. After 30 days, VTM [113.6 (17.7)] and KTX [82.4 (13.4)] maintained the highest microhardness values with C-I, and KTX [71.3 (17.6)] maintained the best result with C-IV.Conclusion: After 30 days, the different used manipulation conditions affected the final microhardness values of VTM and MXR glass ionomer cements. KTX was the least affected by the manipulation conditions...
Subject(s)
Humans , Glass Ionomer Cements/chemistry , Dental Materials , Hardness Tests/instrumentation , Analysis of Variance , Data Interpretation, StatisticalABSTRACT
The present study was undertaken to evaluate the effect of dentifrices containing low fluoride concentrations on microhardness of sound enamel in 50 healthy young premolar teeth. They were divided into five different groups according to the concentrations of fluoride in dentifrice used. The Vickers hardness of enamel was measured using a Zwick microhardness tester under 1000 g load and a Vickers indenter before and after the application of fluoride dentifrices. The results of the present study suggest that low fluoride concentration dentifrices are as effective as the higher concentrations in increasing the hardness of enamel.
Subject(s)
Analysis of Variance , Bicuspid/drug effects , Dental Enamel/drug effects , Dentifrices/pharmacology , Dose-Response Relationship, Drug , Fluorides/pharmacology , Hardness/drug effects , Hardness Tests/instrumentation , Humans , Time FactorsABSTRACT
Os autores estudam a microdureza de 3 resinas compostas fotopolimerizável com tempo de exposição cronometrado em 40 segundos. Para estabelecer relação de causa e efeito foram medidas o comprimento de onda e a intensidade luminosa de cada um dos sistemas ópticos destes aparelhos