Effects of Different Polymerization Time on Surface Hardness of Packable Composites

Abstract

The aim of the present study was to determinethe effect of 20 seconds and 40 seconds exposuretime on top and bottom surface hardness of packable composites. Four different packable composites P60, Surefil, Solitare 2 and Pyramid-Dentin were placed in 2 mm depth and 8 mm diameter ofplexiglass mould n=20 . Specimens were polymerized with halogen light curing unit 600 mW/cm2 for 20 seconds or 40 seconds. Knoop HardnessTester was used for microhardness recordings.Microhardness data were analyzed using 1-wayANOVA and Tukey HSD test. Top and bottommicrohardness values from highest to lowest wereas follows: P60> Surefil> Solitare 2 = PyramidDentin. Curing time 20 sec or 40 sec did not havean effect on top surface microhardness in mostcomposites except Surefil. 40 sec polymerizationgave way to higher microhardness values than 20sec polymerization in Surefil

Keywords

• Packable composite, surface hardness, exposure time

FARKLI POLİMERİZASYON ZAMANLARININ KONDANSE EDİLEBİLİR KOMPOZİT REZİNLERİN YÜZEY SERTLİĞİ ÜZERİNE ETKİLERİ

Abstract

Bu çalışmanın amacı dört farklı kondanseedilebilir kompozitin 20 sn ve 40 sn ışık uygulamasısonucu oluşan alt ve üst yüzey sertlik değişiklerininincelenmesidir. Yüzey sertlik ölçümleri için dörtfarklı kondanse edilebilir kompozit P60, Surefil,Solitare 2 ve Pyramid-Dentin 2 mm kalınlığında ve8 mm çapında pleksi glass kalıp içerindeki boşluklara yerleştirildi n=20 . Polimerizasyonlar halojenbir ışık kaynağı kullanarak 600 mW/cm2 20 sn n=40 ve 40 sn n=40 olacak şekilde polimerize edilen örnekler, Knoop Hardness KHN testi ile yüzey sertlik değerleri ölçüldü. İstatistiksel değerlendirme tek yönlü varyans analizi ANOVA ile yap›ld› ve gruplar aras› farkl›klar Tukey testi ile belirlendi.En yüksek üst ve alt yüzey sertliği s›ras› ile P60> Surefil> Solitare 2 = Pyramid-Dentin olarak tespit edildi. Iş›k uygulama süresi 20 sn veya 40 sn Surefil kompozit d›ş›nda kompozitlerin birçoğunda üst yüzey sertlik değerlerini değiştirmedi. Sadece Surefil kompozit grubunda 40 sn polimerize edilen örnekler, 20 sn polimerizasyona göre daha fazla sertlik değeri gösterdi.

Keywords

• Kondanse edilebilir kompozit, yüzey sertliği, ›ş›k uygulama süresi

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