FARKLI AKRİL TEPİM YÖNTEMLERİNİN AKRİLİK MALZEMENİN MEKANİK ÖZELLİKLERİNE ETKİSİNİN İNCELENMESİ

Öz

Amaç: Çal$ mam$z$n amac$, iki farkl$ akril muflalama tekni3inin akrilik rezinlerin bükülme dayan$m$ve sertlikleri üzerindeki etkisi incelenmektir. Gereç ve Yöntem: Çal$ mada iki farkl$ grup ve materyal olarak da her grup içinde iki farkl$ materyal test edildi: konvan- siyonel yöntemle muflalanan Meliodent ve Entacryl, enjeksiyon yöntemiyle muflalalan Ivocap Plus ve Meli-dent. Her bir alt grup için 8 adet örnek (65mm uzunluk, 10 mm geni lik, 2.5mm yükseklik) haz$rland$. Örneklerin bükülme dayan$mlar$ üniversal test cihaz$nda üç nokta bükülme testi uygulanarak bulundu (5 mm/ dakika ba l$k h$z$). K$r$lan örnekler daha sonra sertlik testleri için kullan$ld$. Dijital mikro sertlik test cihaz$ kullan$larak, her bir örnek için Knoop sertlik de3eri tespit edildi. Bulgular: Entacryl istatistiksel olarak (p0.05). Enjeksiyon yöntemi kullan$larak muflalan$lan Meliodent’in istatistiksel olarak en dü ük bükülme dayan$m$na sahip oldu3u tespit edildi (p0.05). Ivocap Plus’$n istatistiksel olarak en dü ük sertlik de3erine sahip oldu3u tespit edildi (p

Anahtar Kelimeler

• bükülme dayan$m$
• sertlik
• enjeksiyon muflalama

THE EVALUATION OF THE EFFECTS OF DIFFERENT ACRYLIC MOLDING TECHNIQUES ON THE MECHANICAL PROPERTIES OF ACRYLIC RESINS

Öz

Purpose: The purpose of this study was to investigate the effects of two different acrylic molding techniques on flexural strength and hardness of acrylic resins. Material and Method: In this study, two different test groups were used; with conventional molding method Meliodent and Entacryl, with injection molding method Ivocap Plus and Meliodent. For each group, 8 specimens for each material ( 65 mm length, 10 mm width, 2,5 mm height) were prepared. The flexural strength (FS) values of the specimens were assessed by 3 point bending test using a universal testing machine (5mm/min crosshead speed) and then the fractured specimens were used for the determination of the Knoop hardness number (KHN) using a digital micro-hardness tester.
Results: As for the flexural strength values, as Entcryl has (p<0.05) the highest strength value, Meliodent with conventional molding method is the second and Ivocap Plus Plus material is the third turn. But there is no statistically signifigant differences between two materials (Meliodent and Ivocap) (p>0.05). Meliodent with injection molding has the lowest flexural strength values (p<0.05). The Meliodent with conventional molding method is the hardness material, the Meliodent and Entacryl with injection molding follows it in turn. Ivocap Plus has the lowest hardness value (p<0.05). Conclusion: When injection molding technique used with the specially prepared material, flexural strength and hardness values are acceptable. There is no advantage when the traditional acrylic material molded with ivocap plus.

Anahtar Kelimeler

• flexural strength
• hardness
• injection molding

Kaynakça

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