Initial Mechanical Stabilization of Conventional Glass Ionomer Cements with Different Active Principles

ABSTRACT Objective: To determine the initial mechanical stabilization of conventional glass ionomer cements (GICs) indicated for the atraumatic restorative treatment (ART) in different storage periods. Material and Methods: Specimens were divided according to the GIC (n=12): IZ - Ion-Z, KM - Ketac Molar Easymix, RS - Riva Self Cure, and GL - Gold Label 9. They were prepared and stored in distilled water. Superficial microhardness (SMH) was evaluated (KHN) in three phases: (A) after 1, (B) 3, and (C) 7 days of storage. Data were submitted to 2-way ANOVA and Tukey tests (α = 5%). Results: The average KHN values for phases A, B, and C were, respectively, 33.05 ± 9.74; 33.21 ± 10.31 and 52.07 ± 11.75 (IZ); 50.35 ± 11.39; 66.05 ± 10.48 and 67.77 ± 13.80 (KM); 89.63 ± 15.59; 71.31 ± 23.86 and 57.70 ± 16.89 (RS); 42.18 ± 9.03; 68.54 ± 6.83 and 57.95 ± 8.24 (GL). Significant differences were observed: GIC, time, and interaction of both (p<0.05). KHN values differed between the groups, except in the GIC parameter for KM and GL. The time parameter values of phase A were lower than those of B and C, except for IZ and RS. Conclusion: The initial mechanical stabilization differed between the types of GIC tested and the storage time, and after the final period, all had similar SMH.

Effect of edta and qmix ultrasonic activation on the reduction of microorganisms and endotoxins in ex vivo human root canals

Abstract The present study aimed to compare the effectiveness of QMiX and 17% EDTA associated to passive ultrasonic irrigation (PUI) or manual agitation (MA) on the reduction of E. faecalis, E. coli and LPS from root canals. Forty single rooted human teeth were randomly divided into four groups (n=10), according to the final irrigation protocol: EDTA+MA, QMiX+MA, EDTA+PUI, QMiX+PUI. Sample collections were obtained from the root canal content immediately before preparation (baseline-S1), after instrumentation (S2), after final irrigation protocol (S3) and 7 days after instrumentation and final irrigation (S4). The antimicrobial effectivity and on endotoxin content were analyzed by culture procedure (CFU/mL) and LAL assay (EU/mL), respectively. The results were statistically analyzed by Kruskal-Wallis and Friedman test (α=5%). QMiX+MA and QMiX+PUI reduced 100% of E. coli and E. faecalis bacteria and also prevented E. faecalisregrowth at S4. EDTA significantly reduced E. coli, but it was not effective in reducing E. faecalis. All protocols reduced EU/mL when compared to S1, however at S4 there was a significant reduction of EU/mL only in the QMiX+MA and QMiX+PUI groups in relation to S3 and S2, respectively. Final irrigation with QMiX associated with MA or PUI had superior antibacterial efficacy compared to EDTA, eliminating 100% of E. coli and E. faecalis strains. In addition, QMiX+PUI reduced 97.61% of the initial content of LPS.

Resumo O presente estudo objetivou comparar a eficácia do QMiX e do EDTA 17% associado à irrigação ultrassônica passiva (PUI) ou agitação manual (MA) na redução de E. faecalis, E. coli e LPS de canais radiculares. Quarenta dentes humanos unirradiculares foram divididos aleatoriamente em quatro grupos (n = 10), de acordo com o protocolo final de irrigação: EDTA+MA, QMiX+MA, EDTA+PUI, QMiX+PUI. Coletas das amostras foram obtidas a partir do conteúdo do canal radicular imediatamente antes do preparo (inicial-S1), após a instrumentação (S2), após o protocolo final de irrigação (S3) e 7 dias após a instrumentação e irrigação final (S4). A eficácia antimicrobiana e o conteúdo de endotoxina foram analisados ​​por procedimento de cultura (UFC/mL) e ensaio LAL (EU/mL), respectivamente. Os resultados foram analisados estatisticamente pelo teste de Kruskal-Wallis e Friedman (α = 5%). QMiX+MA e QMiX+PUI reduziram 100% das bactérias E. coli e E. faecalis e também preveniram a recolonização de E. faecalis em S4. O EDTA reduziu significativamente E. coli, mas não foi eficaz na redução de E. faecalis. Todos os protocolos reduziram EU/mL quando comparados com S1, no entanto, no S4 houve uma redução significativa de EU/mL apenas nos grupos QMiX+MA e QMiX+PUI em relação a S3 e S2, respectivamente. A irrigação final com QMiX associada a MA ou PUI apresentou eficácia antibacteriana superior em relação ao EDTA, eliminando 100% das cepas de E. coli e E. faecalis. Além disso, QMiX+PUI reduziu 97,61% do conteúdo inicial de LPS.