RESUMO
Background In adhesive dentistry, creating a long-lasting bond between resin composite and dentin is crucial. The durability of this bond dramatically depends on the structural integrity of collagen fibrils present in the hybrid layer. However, matrix metalloproteinases (MMPs) can degrade collagen fibrils, compromising the bond's longevity. Aim The objective is to evaluate the potential effectiveness of natural extracts from Moringa and Centella in preventing collagen degradation caused by MMPs. Material and methods The phenol and flavonoid content of the extracts were evaluated. Dentin beams were demineralized and pre-treated with 1% or 5% Moringa, 1% or 5% Centella, or 2% chlorhexidine (CHX) (five minutes), with untreated beams as control. Beams were incubated in calcium- and zinc-containing media (CM) at pH 7.2 and 37°C for one, 10, 20, and 30 days, and C-terminal cross-linked telopeptide of type I collagen (ICTP) release (collagen telopeptide) was assessed using an enzyme-linked immunosorbent assay (ELISA) kit after 30 days. Results Data were analyzed with a one-way analysis of variance (ANOVA). All test groups showed a different dry mass loss. The control group had the highest loss, followed by CHX, with the least loss in the 5% Moringa and Centella groups. ICTP release ranged from 1.781 ± 0.319 to 3.146 ± 0.684, with 5% Moringa showing the most negligible release. Conclusion The group that received 5% Moringa exhibited the most effective reduction in collagen degradation compared to all the other groups.
RESUMO
Objective: to investigate the effect of two natural cross-linkers on microtensile bond strength (µTBS) and evaluate their influence on the durability of the resin dentin bonds. Material and Methods: the Moringa oleifera and Centella asiatica plant extracts were qualitatively tested with high-performance thin layer chromatography (HPTLC) for the presence of phenols. The phenolic content ranged from 27 to 30 gallic acid equivalents (GAE), µg/mg of dry weight. After etching, two concentrations (5% and 1%) of these two extracts were prepared and used as pretreatment liners on dentin. They were applied for a min. After restoration with resin composite, dentin resin beams were prepared. The study groups were 5% Moringa, 1% Moringa 5% Centella 1% Centella, and control (without cross-linker application). For each group, half of the samples underwent µTBS testing after 24 hours, while the remaining half were immersed in artificial saliva to assess the bond's longevity after 6 months of ageing. Statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test. Results: both 5% and 1% Moringa showed a significant difference (p<0.05) compared to the other groups at both intervals. However, after ageing, the specimens in the control and 1% Centella groups resulted in a significant decrease in µTBS. Conclusion: overall, both concentrations of Moringa (5% and 1%) were effective in stabilising the bond during both intervals.(AU)
Objetivo: investigar o efeito de dois reticuladores naturais na resistência de união (µTBS) à microtração e avaliar sua influência na durabilidade da adesão da resina à dentina. Material e Métodos: extratos das plantas Moringa oleifera e Centella asiatica foram qualitativamente testados através de cromatografia em camada fina de alta performance (HPTLC) para a presença de fenóis. O conteúdo fenólico alcançou entre 27 a 30 equivalentes de ácido gálico (GAE), µg/mg de peso seco. Após o condicionamento, duas concentrações (5% e 1%) dos extratos foram preparadas e utilizadas como forros de pré-tratamento em dentina. Eles foram aplicados por um minuto. Após a restauração com resina composta, palitos de dentina e resina foram preparados. Os grupos foram 5% Moringa, 1% Moringa, 5% Centella, 1% Centella e controle (sem aplicação de reticulador). Para cada grupo, metade das amostras foram submetidas ao teste µTBS após 24 horas, enquanto a outra metade foi imersa em saliva artificial para avaliar a longevidade adesiva após 6 meses de envelhecimento. Foi realizada análise estatística através de ANOVA 1-fator, seguido do teste post hoc de Tukey. Resultados: ambas as concentrações de 5% e 1% de Moringa demonstraram diferença significativa (p<0.05) comparadas aos outros grupos em ambos os intervalos. No entanto, após o envelhecimento, os espécimes dos geupos controle e 1% de Centella resultaram em uma redução significativa de µTBS. Conclusão: no geral, ambas as concentrações de Moringa (5% e 1%) foram efetivas em estabelecer a adesão em ambos os intervalos (AU)