The Effect of Heat Sterilization on Cyclic Fatigue of Niti FlexMaster Root Canal Files

Abstract

The aim of this in-vitro study was to evaluate the effect of heat sterilization on cyclic fatigue resistance of FlexMaster NiTi rotary instruments. Eighty-four FlexMaster NiTi instruments of sizes 20.04, 25.04, and 30.04 were selected and divided into two groups: Group A= 42 new instruments and Group B=42 heat sterilized instruments. Each instrument of group B was sterilized five times. Cyclic fatigue testing of new and sterilized instruments was performed using a device that allowed the instruments to rotate freely inside a stainless steel artificial canal with two different of radii 5mm and 10 mm . The number of cycles to fracture NCF was calculated. The data were analyzed using t-test to determine any statistical significance between new and heat sterilized instruments of the same file size α= .05 . For both radii, the difference in the cyclic fatigue between group A and group B was statistically significant p

Keywords

• Cyclic fatigue, FlexMaster, NiTi instruments, sterilization

STERİLİZASYONUN NİTİ FLEXMASTER KÖK KANAL EĞELERİNİN DÖNGÜSEL YORGUNLUĞUNA ETKİSİ

Abstract

Bu in-vitro çalışmanın amacı sterilizasyonun FlexMaster NiTi eğe sisteminin döngüsel kırılganlığına etkisinin incelenmesidir. Seksen dört adet 20/.04, 25/.04 ve 30/.04 ebatlarında steril FlexMaster NiTi eğe seçilmiş ve iki gruba ayrılmıştır: Grup A=Kırk iki adet kullanılmamış eğe, B= Kırk iki adet sterilize edilmiş eğe. Grup B’deki her ensevtrüman beş kez sterilize edildi. Yeni ve sterilizasyon periyoduna sokulmuş eğelerin döngüsel yorgunluk testi, her bir eğenin içinde rahatça dönebildiği paslanmaz çelikten yapılmış ve iki ayrı kurvatüre sahip 5 mm ve 10 mm yapay kök kanallarında gerçekleştirildi. Enstrümanların kırılma gerçekleşene kadar olan dönüş sayısı hesap edildi. Sonuçlar yeni ve steril edilen eğeler arasında istatistiksel olarak anlamlı bir fark olup olmadığını anlamak için t-testi ile analiz edildi α=.05 . Döngüsel yorgunluk bakımından tüm enstrüman boyutları için Group A ve Grup B arasındaki fark iki ayrı kanal kurvatürü için istatistiksel olarak anlamlı bulundu p

Keywords

• Döngüsel yorgunluk, FlexMaster, NiTi enstrümanlar, sterilizasyon

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