四鈣磷酸鹽填料牙科複合樹脂:填料粒子大小及表面處理對徑向拉伸強度與顏色之影響

Dental composite resin with TTCP as filler: effect of filler particle size and pretreatment on diametral tensile strength and color matching

游傑丞(Chieh-Chen Yu)

指導教授 ： 王震乾

共同指導教授 ： 陳文正(Wen-Cheng Chen)

高雄醫學大學/口腔醫學院/牙醫學研究所/碩士(2012年)

摘要

研究目的：
本研究使用微米與奈米粒徑之四鈣磷酸鹽(tetracalcium phosphate, TTCP)類陶瓷，經過不同表面處理後做為複合樹脂填料，並以不同重量百分比製成齒科樹脂後，觀察複合樹脂性質之徑向拉伸強度與顏色變化。
研究方法：
實驗樹脂以bisphenol A glycidyl methacrylate (Bis‐GMA)與triethylene glycol dimethacrylate (TEGDMA)為基質，採用camphoroquinone (CQ)作為光聚合系統。TTCP粒徑大小分別為10微米、1微米、370奈米、100奈米。TTCP表面處理方法引用並修改自專利製程，表面處理後在穿透式電子顯微鏡(TEM)下觀察形態結構。隨後TTCP加入光聚合樹脂基質中製成實驗試片。不同粒徑大小組別分別以重量百分比30、40、50、60 wt%混合。聚合完成後試片隨即使用萬能材料試驗機(universal testing machine)徑向垂直施壓(速度為1.0mm/min)，紀錄所得數據再經換算為徑向拉伸強度和彈性模數。比色測試則以比色機測量光聚合後、24、48、72小時及7天後的數值，數值記錄為CIELAB (L*, a*, b*)值並以色差公式比較ΔE。資料分析以JMP8.0使用one-way ANOVA、two-way ANOVA、Tukey-HSD test、Student’s t-test等統計方法檢定實驗結果(α=0.05)。
結果：
觀察TTCP粒子可發現經過表面處理後微米顆粒上有奈米鬚晶之形成。統計結果發現，表面處理、填料重量百分比、及無表面處理之100奈米和370奈米比較，對樹脂徑向拉伸強度有顯著之影響(p <0.0001)，但相同表面處理濃度下10微米與1微米對徑向拉伸強度與無顯著影響；表面處理、填料重量百分比與粒徑皆對樹脂彈性模數有顯著之影響(p <0.001)。樹脂顏色方面，填料粒徑在10微米比較其他組別有明顯不同，顏色會隨時間經過而產生變化，表面處理與填料百分比在某些組別中會對顏色產生顯著影響(p <0.0001)。
結論:
1. TTCP表面處理之變化除使電子顯微鏡下產生鬚晶晶相變化，也對樹脂徑向拉伸強度與彈性模數有統計上顯著影響。
2. 樹脂顏色會受到填料粒徑、時間、與填料百分比之影響。填料百分比越高，顏色越穩定。

關鍵字

牙科複合樹脂 ； 四鈣磷酸鹽 ； 徑向拉伸強度 ； 比色

並列摘要

Objectives:
The objective of this study was to observe the properties of dental composite resins, which was composed of micron-to-nano scale of tetracalcium phosphate (TTCP) under different surface pretreatment conditions as reinforced filler. The different mass fraction ratio of fillers within composite resin was prepared and the influences on diametral tensile strength (DTS) and resin color were also investigated.
Materials & Methods:
The resin matrix of testing specimens was composed of bisphenol A glycidyl methacrylate (Bis‐GMA) and triethylene glycol dimethacrylate (TEGDMA), with a light-curing initiator of camphoroquinone (CQ). The particle distributions of TTCP filler were set at 10 μm, 1 μm, 370 nm, and 100 nm. The surfaces pretreat method was adapted from patented TTCP pretreatment thereof and observed under transmission electron microscope (TEM). After pretreatment, TTCP particle was mixed within resin matrix to form test specimens. The ratios of the filler mass fraction to dental composite resin were differed from 30%, 40%, 50%, and 60 wt% (six duplicate specimens were prepared and analyzed for each group, n=6). For mechanical measurements, the diametral tensile tests and recordings of stress versus strain of the specimens were measured immediately after sample curing were reached using a universal testing machine at a crosshead speed of 1.0 mm/min. Color matching test on the sample was recorded using color measuring machine at the different times through the sample being immediate cured, 24 hrs, 48hrs, 72 hrs, and 7 days after light curing. The Commission Internationale de l'Eclairage L*, a* and b* (CIELAB) values and the differences in color (ΔE) were measured. Statistic analysis (JMP 8.0) was done by using one-way ANOVA, two-way ANOVA, Tukey’s HSD post hoc test, or Student’s t-test. (α=0.05).
Results:
TEM observation of pretreated TTCP was showed that nano-scale whisker crystallites were grown on the surface of micron-scale particle. The analysis reported that the DTS was found significantly influenced by the process surface pretreatment on fillers, and different filler mass fractions in 100nm and 370nm group without pretreatment (p <0.0001). In the modulus of elasticity analysis, statistically significant differences were found between the process of surface pretreatment, different filler mass fractions, and particle size distributions (p <0.0001). The color of resins could be distinguished easily between the 10μm and the other groups. The color of resin would change with time after the sample being cured. The color difference ΔE was found statistically significant influenced by pretreatment and filler mass in group comparisons (p <0.0001).
Conclusion:
1. The process of TTCP surface pretreatment not only had an affected by phase changes on the surfaces of crystallites through TEM observation, but also had statistically significant effects in DTS and modulus of elasticity.
2. The color of resin would be influenced by filler particle size distributions, filler mass fraction, and changing with time. The higher the filler mass fraction of resin, the more stablie the resin’s color.

並列關鍵字

dental composite resin ； tetracalcium phosphate (TTCP) ； diametral tensile strength (DTS) ； color matching

參考文獻

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