硫酸鈣型骨水泥的硬化行為與物理特性探討

Setting behavior and physical properties of calcium sulfate cements

黃彥凱(Yan-Kai Huang)

指導教授 ： 段維新

國立臺灣大學/工學院/材料科學與工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202102985

摘要

由於醫療發展越來越進步使得人口平均壽命增加，人口老化或是受傷導致的骨孔洞、骨質疏鬆越來越常見，所以對於骨替代材、骨移植和骨填充材的要求也隨之增加。本研究目的為研究半水硫酸鈣型骨水泥的硬化時間(setting time)以及其物理性質，並試著使其更適合為實際使用。
硫酸鈣主要具有三種型態，二水硫酸鈣 (CaSO4•2H2O)、半水硫酸鈣 (CaSO4•1/2H2O)以及無水硫酸鈣 (CaSO4)。半水硫酸鈣作為骨填充材已將近百年，而其與水進行水和反應的產物二水硫酸鈣有著良好的生物相容性、骨傳導和骨誘導性，以及刺激新骨細胞的生成。整體來說，半水硫酸鈣型骨水泥最大的優勢在於，非常容易塑型，只要加水就能變成二水硫酸鈣，而且可被生物體吸收並完全降解，不用進行二次手術。
本次研究，第一部分是將蒸餾水與半水硫酸鈣粉末以粉水比 (LPR value) = 0.6, 0.8, 1.0, 1.2, 1.4混合，用維克氏針 (Vicats needle) 測定其硬化時間的變化，並量測其物理性質包括密度、壓縮強度、彎取強度，最後再進行微結構分析以及相分析。
除了研究粉水比對骨水泥造成的影響，這次研究也會在半水硫酸鈣粉末中混入不同量的二水硫酸鈣粉末，起因是因為過去的研究指出，二水硫酸鈣可以加快半水硫酸鈣進行水合的時間，也就是降低硬化時間。最後會將溶劑從蒸餾水替換成高磷酸根溶劑 (high phosphate content solution, HPS) ，實驗結果顯示，磷酸根離子參與反應，會使產物的結構發生變化，並且使半水硫酸鈣型骨水泥的強度上升。
最終實驗結果顯示，隨著粉水比的下降會使硬化時間變短，密度和強度都會上升，可以藉此調整硫酸鈣的硬化時間，但要注意如果加入的水量太少會使材料無法和液體混合出均勻的漿料。而添加一定量的二水硫酸鈣雖可以使硬化時間下降，但是會使材料的密度、強度都下降，而使得原本強度就低的硫酸鈣骨水泥更難以被實際使用。如果將溶劑替換成高磷酸根溶劑酸雖然使得硬化時間上升，但是還是在可使用範圍，而其可以讓材料強度上升，因此本實驗認識添加磷酸根離子是使硫酸鈣骨水泥更接近實際使用的方法之一。

關鍵字

硫酸鈣 ； 水粉比 ； 骨水泥 ； 磷酸鈣 ； 密度 ； 壓縮強度 ； 撓曲強度 ； 析出

並列摘要

Due to the advances in medical treatment, the average life expectancy of the population has increased, so bone defects and osteoporosis caused by aging or injuries have become more common. Therefore, the demands for bone substitutes, bone grafts and bone fillers have also increased. The purpose of this work is to study the setting time of calcium sulfate hemihydrate type bone cement and its physical properties, and try to make it more suitable for surgery.
There are three main types of calcium sulfate, calcium sulfate dihydrate, calcium sulfate hemihydrate, and calcium sulfate anhydrate. Calcium sulfate hemihydrate has been used as a bone filler for nearly a hundred years, and the product of hydration is calcium sulfate dihydrate that has good biocompatibility and osteoconductivity. It can stimulate the formation of new bone cells. On the whole, the advantage of calcium sulfate hemihydrate type bone cement is that it is very easy to form. As long as water is added, it can become calcium sulfate dihydrate, and it can be absorbed and completely degraded by human body without secondary surgery.
In this study, the first part is to mix distilled water with calcium sulfate hemihydrate powder at LPR value (liquid/powder) = 0.6, 0.8, 1.0, 1.2, 1.4, and use vicats needle to measure the setting time and measure its physical properties including density, compressive strength, flexural strength, and finally conduct microstructure analysis and phase analysis. In addition to studying the effect of LPR value on bone cement, this study will also mix different amounts of calcium sulfate dihydrate powder with calcium sulfate hemihydrate powder. The reason is that past studies had pointed out that calcium sulfate dihydrate can speed up the hydration of calcium sulfate hemihydrate, that is, reduce the setting time. Finally, the solution can be replaced from distilled water to high phosphate content solution (HPS). The experimental results show that the participation of phosphate ions in the reaction will change the structure of the product and increase the strength of the calcium sulfate hemihydrate type bone cement.
This work shows that as LPR value decreases, the setting time is shorter, and the density and strength is increased. This can be used to adjust the setting time of calcium sulfate, but it should be noted that if the amount of water added is too low, the material can not be mixed with the liquid to form uniform slurry. Although adding a certain amount of calcium sulfate dihydrate can reduce the setting time, it would reduce the density and strength of the material, making it is more difficult to actually used. If the solution is replaced with a high phosphate solvent, although the setting time increases, it is still in the usable range, and it can increase the strength of the material. Therefore, this experiment recognizes that the addition of phosphate ions makes calcium sulfate bone cement easier to be used.

並列關鍵字

calcium sulfate ； liquid powder ratio ； bone cement ； calcium phosphate ； density ； compressive strength ； flexural strength ； precipitation

參考文獻

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