Effect of setting atmosphere on apatite cement resorption: An in vitro and in vivo study. (December 2018)

• Record Type: Journal Article
• Authors: Cahyanto, Arief; Tsuru, Kanji; Ishikawa, Kunio
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 88(2018)
• Page Start: 463
• Page End: 469
• Publication Date: 2018-12
• Subjects: Apatite cement -- Carbonate apatite -- Setting atmosphere -- Replacement by bone; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2018.08.021
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: Objectives: The aim of this present study was to investigate the effect of setting atmosphere on replacement of apatite cement with new bone both in vitro and in vivo . Material and methods: Apatite cement consisting of an equimolar mixture of tetracalcium phosphate and anhydrous dicalcium phosphate was mixed with distilled water and allowed to set at 37 °C and 100% relative humidity under 0%, 5%, and 100% CO2 atmospheres. X-Ray diffraction and Fourier Transform Infrared Spectroscopy were employed to confirm the carbonate apatite formation. Micro-CT and histological evaluation was made at 1 and 6 month(s) using twelve 10-week-old specific-pathogen-free male Wistar rats. Results: B-type carbonate apatite was found when the apatite cement was set under 100% CO2 and 5% CO2 . More carbonate apatite was formed in the case of 100% CO2 when compared with 5% CO2, and none was formed under 0% CO2 . Interestingly, unreacted tetracalcium phosphate was significant when apatite cement was set under 0% CO2, indicating the formation of Ca-deficient hydroxyapatite. When a bone defect of rat tibia was reconstructed in these conditions of apatite cement and sintered hydroxyapatite, replacement of the apatite cement was confirmed 6 months after implantation, whereas no replacement was observed in the case of sintered hydroxyapatite. The amount of replacement of apatite cement with bone was greater, on the order of 100% CO2 and 5% CO2, followed by 0% CO2 . Conclusion: The results obtained in the present study demonstrated that setting atmosphere clearly plays an important role in the replacement of set apatite cement with bone.