Influence of two natural cross-linkers on microtensile bond strength durability ­ An in vitro study / Influência de dois reticuladores naturais na durabilidade da resistência de união à microtração ­ Um estudo in vitro

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)

Comparative evaluation of Chloroquick with Triphala, sodium hypochlorite, and ethylenediaminetetraacetic acid on the microhardness of root canal dentin: An in vitro study.

BACKGROUND: Irrigating solutions used for the elimination of microorganisms during root canal preparation affect the chemical and physical properties of dentin, thereby rendering the tooth more prone to fracture. Therefore, the careful and judicious selection of irrigant is required which has maximum benefits with minimum undesirable properties. AIM: The study aimed to compare and evaluate the effect of Chloroquick with composition of 18% etidronic acid+ 5% sodium hypochlorite (NaOCl) with other irrigants such as Triphala, NaOCl, and ethylenediaminetetraacetic acid (EDTA) on the microhardness of root canal dentin. METHODS: Forty freshly extracted non-carious single-rooted human teeth were collected and decoronated at CEJ to standardize the canal length. The roots were sectioned longitudinally to get two halves. Baseline microhardness evaluation was done using Vickers microhardness test before the immersion in irrigants; samples were then randomly divided into four groups (n=20), based on the irrigant used as follows: Group 1 - Saline; Group 2 - 5% NaOCl +17% EDTA; Group 3 - Triphala; and Group 4 - Chloroquick. Later, the samples were immersed in the irrigating solutions for 15 min at 37°C for each group and were then subjected to post-treatment microhardness testing. Microhardness values were recorded and statistically analyzed using one-way ANOVA and intergroup comparison with post hoc Tukey test (P<0.05). RESULTS: The results of the present study showed that all the tested specimens showed a decrease in the microhardness values following application of different irrigating solutions except the control group. The use of Triphala and Chloroquick has minimal effect on the microhardness of root canal dentin post-treatment when compared with 5% NaOCl and 17% EDTA. CONCLUSION: Chloroquick, as well as 0.005% Triphala, can be used safely as an irrigating solution with less detrimental effects on the hardness of root dentin. RELEVANCE FOR PATIENTS: The newer irrigant Chloroquick shows less effect on dentin microhardness, thereby reducing the incidence of root fractures in patients postoperatively.