DİLEK TÜRKAYDIN, Fatıma Betül BAŞTÜRK, Mohammad Hossein NEKOOFAR, Mahir GÜNDAY, Paul DUMMER

Does the mixing and placement regime affect the pH of Mineral Trioxide Aggregate?

Aim:The objective of this study was to measure in a laboratory setting the pH of tooth coloured ProRoot MTA and MTA Angelus following various mixing and placement techniques, including mechanical mixing, manual mixing and indirect ultrasonic activation. Materials and Method: Tooth coloured ProRoot MTA and White MTA Angelus were used. One gram of each powder was mixed with a 0.34 g of distilled water that were allocated to eight experimental groups, each containing three specimens. Four groups were prepared by mechanical mixing of capsules for 30 s at 4500 rpm the other four were mixed manually. Half of the specimens in each group were placed in moulds using indirect ultrasonic activation. pH values were recorded directly from within the freshly mixed material and were analyzed using one-way ANOVA at a 0.05 level of significance. Results: No significant difference in pH was found between the mixing and placement techniques or the materials tested. The highest pH value recorded was in the ProRoot group that was mixed manually and placed ultrasonically (11.64). The Angelus group, which was mixed manually without an ultrasonic agitation, had the lowest pH values (10.42). Conclusion: Mechanical mixing and ultrasonication conferred no significant disadvantage in terms of the initial pH of the material. Since mechanical agitation of encapsulated cements provides more consistent mixes, it might be possible to use this technique combined with ultrasonic agitation as an alternative to manual mixing, both in clinical and in laboratory conditions, in order to achieve standardization of the material so as to enhance its properties.

Karıştırma ve yerleştirme teknikleri Mineral Trioksit Agregatının pH değerini etkiler mi?

Amaç: ProRoot MTA ve MTA Angelus'un mekanik ve elle karıştırma teknikleriyle karıştırılıp, indirekt ultrasonik aktivasyon ile yerleştirilmesinin materyalin pH değerleri üzerindeki etkisini in vitro olarak incelemektir. Gereç ve Yöntem: Beyaz ProRoot MTA ve beyaz MTA-Angelus kullanılmıştır. Bir gramlık toza 0,34 g distile su eklenmiş ve sekiz grup hazırlanmıştır. Grupların yarısı, kapsüllere yerleştirilerek 4500 rpm hızda 30 sn boyunca karıştırılmış, diğer yarısı ise elle karıştırılmıştır. Hazırlanan bu karışımların yarısına indirekt ultrasonik aktivasyon uygulanmıştır. Numunelerin pH değerleri karışım hazırlandıktan hemen sonra ölçülmüş ve değerler one-way ANOVA ile 0,05 anlamlılık düzeyinde değerlendirilmiştir. Bulgular: Test edilen materyaller bazında, karıştırma ve yerleştirme tekniklerinin arasında herhangi bir anlamlı fark bulunamamıştır. En yüksek pH değeri elle karıştırılıp ultrasonik aktivasyon uygulanan ProRoot grubunda (11,64), en düşük pH değeri ise elle karıştırılıp ultrasonik aktivasyon uygulanmayan MTA Angelus grubunda kaydedilmiştir (10,42). Sonuçlar: Mekanik karıştırma ve ultrasonik aktivasyon, mater yalin pH değeri üzerinde herhangi bir olumsuz etki göstermemiştir. Karıştırma ve yerleştirme teknikleri materyalin pH değerleri üzerinde herhangi bir etkiye sebep olmamıştır. Kapsüller içerisindeki simanların mekanik olarak karıştırılmasının daha tutarlı kıvamda karışımlar hazırladığı göz önünde bulundurulursa, bu tekniği ultrasonik aktivasyonla birlikte uygulamak hem klinik hem de laboratuvar koşulları altında standardizasyonun sağlanması açısından bir alternatif olarak düşünülmelidir.

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