Yusuf EMES, Mehmet İPEKOĞLU, Hilal HAZNEDAROĞLU, HALİM İŞSEVER, Serhat YALÇIN, Sabri ALTINTAŞ

Dondurup kurutma ve solventlerle dehidrasyon işlemlerinin kortikal kemiğin eğme dayanımı ve kalsiyum içeriğine etkileri

Amaç: Bu çalışmada iki farklı allogreft saklama yöntemi, dondurup kurutma ve solventlerle dehidrasyon işlemlerinin, greft materyalinin mekanik özelliklerine etkilerinin incelenmesi amaçlandı. Çalışma planı: Sığır kemiklerinden elde edilen bloklar üç gruba ayrıldı. Gruplardan ilki dondurup kurutma, ikincisi solventlerle dehidrasyon işlemlerine tabi tutuldu. Üçüncü grup kontrol grubu olarak hiçbir işlem görmedi. Tüm örneklere üç nokta eğme testi uygulanarak, grupların eğme dayanımları incelendi ve kalsiyum içerikleri değerlendirildi. Bulgular: Dondurulup kurutulmuş ve solventlerle dehidrate edilmiş örneklerin dayanım değerlerinin kontrol grubuna göre anlamlı azalma gösterdiği belirlendi. Ayrıca, sadece solventlerle dehidrate edilmiş örneklerin kalsiyum içeriğinin kontrol grubundan anlamlı olarak düşük olduğu bulundu. Çıkarımlar: Her iki saklama yönteminin, greft materyalinin mekanik özelliklerini azaltması nedeniyle kemiğin eğme dayanımına olumsuz etkileri olduğu düşünülmektedir.

The effects of freeze drying and solvent dehydration on the bending strength and calcium content of cortical bone

Objective: The aim of this study was to investigate the effects of the freeze drying and solvent dehydration allograft preservation methods on the mechanical properties of the graft material. Methods: Bone blocks obtained from bovine humeri were divided into three groups. Samples in the first group were freeze dried, samples in the second group were dehydrated by solvents and samples in the third group were used as controls. All samples underwent three point bending test to investigate bending strength and were evaluated for calcium content. Results: Bending strength of both the freeze-dried and solvent-dehydrated samples were found to have decreased significantly compared to that of the control group. The calcium content of the solvent dehydrated group was also significantly lower than that of the control group. Conclusion: Our results suggested that both preservation techniques, used to dehydrate bone, have negative effects on the bending strength of bone as they decrease the mechanical properties of the graft material.

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