牙科黏合劑操作性質的量化分析方法：玻璃離子體的初探性研究

A quantitative method to analyze manipulation property of dental cement: a pilot study with glass-ionomer cement.

葉昭孝(Chao-Hsiao Yeh)

指導教授 ： 林哲堂

臺北醫學大學/口腔醫學院/牙醫學系碩博士班/碩士(2013年)

摘要

牙科黏合劑是臨床操作上具有廣泛用途的材料，在研發階段就需針對材料進行許多的測試，包括了薄膜厚度、淨凝固時間、抗壓強度等；除此之外，在臨床操作上還要依據建議的粉液比、操作時間、溫度及濕度控制才能達到理想的材料性質。牙科黏合劑的調拌方式都是基於製造廠商的建議與牙醫師本身的經驗，而傳統上的檢測方法又缺乏精確科學化說明，往往會受到許多誤差因素影響，造成後續臨床操作上時間的浪費或是治療的失敗，因此本研究中，提出更加可靠的檢測方法來說明黏合劑混和後性質的變化。

利用質地分析儀(Texture Analyser TA.Xtplus, Stable Mircro Systems, Surrey, UK)具有多種性質測試的機能，能夠對混和後的牙科黏合劑進行連續地記錄，實驗首先採用玻璃離子體黏合劑(GC Fuji IITM, GC)，於調拌後放置於不鏽鋼夾具組中，接著垂直上下直徑10 mm質地分析儀用探測頭記錄出混和結束後至黏合劑達到凝固狀態時期間性質上的變化，藉由測量得到的結果分析出黏合劑於不同操作時間、不同凝固時間內性質變化的趨勢，並且另外做出符合臨床使用時玻璃離子體的操作時間及凝固時間來與廠商建議的時間做統計分析(paired t-test)的比較。

實驗結果顯示在操作時間內，觀察到每次測量的壓力最大值有上升的趨勢，上升斜率也開始變大。而拉力最大值則呈現一緩慢上升的狀態；當超過操作時間後，壓力最大值開始快速的上升，並且於170~180秒時達到上升最大的幅度，拉力最大值上升的幅度雖然不像測到的壓力最大值一樣大，但是仍舊能觀察到拉力最大值的紀錄在170~180秒之間達到最高峰。接著，當玻璃離子體黏合劑超過了製造廠商建議的凝固時間，可以觀察到壓力最大值進入了另一段高原期，到後期幾乎已趨近平緩。另外觀察到拉力最大值的部分，也處於繼續下降的狀態，到後期幾乎沒有測量到有明顯的拉力。另外統計分析(paired t-test)的結果，在廠商建議的操作時間和凝固時間與本實驗測得的操作時間和凝固時間範圍間，GI黏合劑的狀態是有顯著的不一樣的。

討論與未來實驗方向：質地分析儀可以得到比傳統檢測方法更精確且更科學化的測量數據，藉由質地分析儀測得的數據經過分析比較後，能夠說明不同時間區間時材料特性的變化。未來的研究方向首先須交叉驗證本實驗利用質地分析儀測試的精確性和可行性，並針對數據做一些數學上的分析，檢查是否能得到某個趨勢說明或是可代入的公式，期望將來可以用此儀器測試不同的牙科黏合劑或是材料，取代傳統的檢測方法來對材料的性質做更加科學性的分析。

關鍵字

牙科黏合劑 ； 玻璃離子體 ； 質地分析儀 ； 操作時間 ； 凝固時間

並列摘要

Objective. Every kind of dental cements possesses its unique handling characteristics. In the development of the material, properties as film thickness, net setting time and compressive strength need to be tested and complied the standard requirements. The powder/liquid ratio, working time, temperature and moisture also affect the properties of cement during the clinical manipulation. To date the mixing methods are merely instructed by suggestions of the manufacturer, which base on the traditional testing methods. These unspecified methods are lacking of details and easily influenced by many unfavorable mixing errors which may cause time wasting or treatment failure during clinical practice. The aim of this study was to establish a more reliable method to test and investigate the manipulate process and the performance of cement after mixed.

Materials and methods. A Texture Analyser TA.Xtplus (Stable Mircro Systems, Surrey, UK) equipped with a 30 kg load cell was used to measure the property change of GI cement (GC Fuji IITM, GC). A flat-ended stainless-steel probe of 10 mm in diameter was attached to the load cell. The GI cement was mixed and placed in a cylindrical stainless-steel mold with an area much larger than the probe and was carefully checked for leveling. The probe was slowly brought downwards (1 mm/s) to squeeze the sample and subsequently pulled back at a set speed (1 mm/s) and repeated the motion 50 times. The maximum compressive and tensile force (F+ and F- ), the work used to compress and separation (W+ and W-), and the gradient of maximum force change during time period (G+ and G-) were determined using Texture Exponent 32 software version 6.0. The test was repeated 30 times and an average was taken. All experiments were conducted at room temperature (23 ± 1 ℃) and open atmosphere. According to this test method, the trend of the cement property change during the working time or setting time was analyzed. On the other side, we recorded the clinical working and setting time of the GI cement, and compared to manufacturer’s working and setting time of the properties of GI cement with paired t-test.

Result. During the available working time period, the maximum compressive forces and the forces change gradients were in the potential of increasing. The tensile forces were observed increasing slowly during this period of time. When the mixed cement crossed the working time, the compressive forces increased rapidly and the increasing gradients reached the highest peak among 170~180 second as well as the maximum tensile forces. After the cement entered the setting time, the maximum compressive forces became a plateau and the maximum tensile forces were almost insignificant. All the works showed the similar performances to the forces. And the tensile force change gradients were observed reasonable regular pattern only before the setting time. In the statistical analysis, paired t-test of the properties of GI cement showed significant difference between our recorded working and setting time and manufacturer’s working and setting time.

Conclusion. The method of this study is allowed to record the property performance of the cement more precisely than traditional way. Further analysis of the data was required to find a trend or a rule to explain the property change before and after the working time and setting time period. In the future study, other kinds of dental cements will use to be measured by this novel method for further comparison.

並列關鍵字

dental cement ； glass-ionomer ； texture analyzer ； working time ； setting time

參考文獻

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