Comparison of mechanical properties of polyethylene and polyurethane blocks as model materials for in vitro cortical bone modelling

Abstract

Aims: The aim of this study was to compare polyethylene (PE) and polyurethane (PU) blocks at a density of 60 pcf in terms of flexural strength (FS), elastic modulus (EM), elongation, and hardness in vitro for use in cortical bone modelling. Methods: This in vitro study was conducted at Van Yüzüncü Yıl University Faculty of Dentistry Department of Orthodontics and the testing and laboratory phases of the study were conducted at Van Yüzüncü Yıl University Faculty of Dentistry Research Laboratory. PE (group 1) and PU (group 2) blocks with a density of 60 pcf (0.96 g/cm3) were used in the study. The 3-point bending test was performed on a universal testing machine and FS, EM, elongation, and hardness were measured. A total of 30 samples, 15 in the PU group and 15 in the PE group, were included in the study. Results: The FS and hardness values of PE and PU did not show statistically significant differences (p>0.05). Statistically significant differences were found between the PE and PU groups for EM and elongation values (p<0.05). Conclusion: This study showed that PE blocks can be used in orthodontics for in vitro cortical bone modelling.

Keywords

• Polyethylene block
• polyurethane block
• cortical bone
• orthodontics
• flexural strength
• elastic modulus

In vitro kortikal kemik modellemesi için model malzeme olarak polietilen ve poliüretan blokların mekanik özelliklerinin karşılaştırılması

Abstract

Amaçlar: Bu çalışmanın amacı, kortikal kemik modellemesinde kullanılmak üzere 60 pcf yoğunluktaki polietilen (PE) ve poliüretan (PU) blokları eğilme dayanımı (FS), elastik modül (EM), uzama ve sertlik açısından in vitro olarak karşılaştırmaktır. Yöntemler: Bu in vitro çalışma Van Yüzüncü Yıl Üniversitesi Diş Hekimliği Fakültesi Ortodonti Anabilim Dalı'nda, çalışmanın test ve laboratuvar aşamaları ise Van Yüzüncü Yıl Üniversitesi Diş Hekimliği Fakültesi Araştırma Laboratuvarı'nda yürütülmüştür. Çalışmada 60 pcf (0,96 g/cm3) yoğunluktaki PE (grup 1) ve PU (grup 2) bloklar kullanılmıştır. 3 nokta eğme testi üniversal test cihazında yapılmış ve FS, EM, uzama ve sertlik ölçümleri yapılmıştır. Çalışmaya PU grubunda 15 ve PE grubunda 15 olmak üzere toplam 30 örnek dahil edilmiştir. Sonuçlar: PE ve PU'nun FS ve sertlik değerleri istatistiksel olarak anlamlı bir fark göstermedi (p>0,05). PE ve PU grupları arasında EM ve uzama değerleri için istatistiksel olarak anlamlı farklar bulundu (p<0,05). Sonuç: Bu çalışma, PE bloklarının in vitro kortikal kemik modellemesi için ortodontide kullanılabileceğini gösterdi.

Keywords

• Polietilen blok
• poliüretan blok
• kortikal kemik
• ortodonti
• eğilme dayanımı
• elastik modül

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