| 摘要: | The purpose of this study was to develop a novel soluble calcium compound based teeth remineralization patches. The calcium lactate phosphate (CLP) was designed and synthesized by wet chemical method. The calcium oxide added to the mixture with various molar ratios of lactic acid and phosphoric acid under stirring for different time periods. After 1 hr, 3 hrs, 6 hrs, 12 hrs and 24 hrs synthesizing, the CLP solution was first filtered and then freeze dried (liquid phase). The crystalline structure, Ca/P ratio, solubility, functional groups and thermogravimetric properties of harvested CLP were analyzed by x-ray diffractometer (XRD), x-ray fluorescence (XRF), moisture analyzer, Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), respectively. The double-layer teeth remineralization patches include material layer for good mucoadhesion and CLP releasing, while the backing layer for anti-adhesion. The in vitro remineralization test was conducted by using human teeth (etched by 1 M acetic acid for 3 mins). The experiment groups were deionized water (control) and artificial saliva (positive control). Teeth remineralization patches containing 1% CLP, 3% CLP and 5% CLP were used as experimental groups. Knoop Hardness Number (KHN) for etched enamel before and after treatment by patches from microhardness assay was utilized to index teeth remineralization. The measured solubility of CLP was 8.0 g/100 ml H2O at 25°C, and it is significantly higher than the solubility of amorphous calcium phosphate (< 0.01 g/100 ml H2O at 25°C). The XRD diagram for CLP showed no obvious diffraction peaks indicating the amorphous nature of CLP compounds. The Ca/P mole ratio was about 4.5 according to the XRF measurement. After applying teeth remineralization patches with 3% and 5% CLP to etched enamel surface for 15 mins, the % hardness recovery showed 39.7 ± 39.1% and 56.5 ± 43.8% (p < 0.05 by paired t-test). It is significantly higher than artificial saliva (-12.2 ± 19.2%). In addition, the remineralization effect of CLP also could be using as a dentinal tubules sealer. The pilot study of using CLP paste on dentinal tubules plugging of was undertaken. The feasibility of CLP used for teeth remineralization was proven.
針對牙釉質表面表淺層酸蝕或腐蝕所造成之去礦化問題，本研究之目的在發展一個新型具高溶解度之磷酸鈣衍生物並應用於牙齒再礦化貼片。本研究之非晶性乳酸磷酸鈣(calcium lactate phosphate, CLP)係利用濕式合成法(wet chemical method)，將氧化鈣加入不同乳酸與磷酸之莫耳比，反應1、3、6、12及24小時並維持攪拌，經固液分離，將所得濾液以冷凍乾燥製成。並使用X光繞射分析儀(XRD)、X光螢光分析儀(XRF) 、水份天秤、傅立葉紅外線光譜儀(FTIR)與熱重分析(TGA)分析其結晶度、鈣磷莫耳比、溶解度、官能基與熱重。而後將乳酸磷酸鈣製作成牙齒再礦化貼片，牙齒再礦化貼片設計具有雙層結構，材料層與支撐層，材料層主要為承載乳酸磷酸鈣與黏附牙齒，支撐層則提供抗沖刷與抗沾黏之功能。將來自捐贈之牙齒以人工酸蝕(1M醋酸酸蝕3分鐘)方式處理，實驗組為含1%、3 %及5% CLP之牙齒再礦化貼片，對照組為去離子水、人工唾液和含3%乳酸鈣之貼片，並使用微硬度計測量牙齒經貼片處理過後之表面硬度及牙釉質密度改變量以評估牙齒再礦化貼片之功效性。以水份天秤烘乾飽和之CLP溶液以測量CLP之溶解度，結果顯示CLP之溶解度為8.0 g/100 ml H2O at 25°C，明顯高於非晶性磷酸鈣之溶解度(< 0.01 g/100 ml H2O at 25°C) ， CLP在XRD圖譜中亦未出現明顯之結晶繞射峰，顯示CLP為非晶性之化合物，壓錠後之CLP經X光螢光分析儀分析結果顯示，鈣磷比(Ca / P mole ratio)約為4.5。將含1%、3%及5% CLP之牙齒再礦化貼片黏貼於牙齒牙釉質表面脫鈣處，經過15 mins、30 mins、1 hr、3 hrs及6 hrs後以微硬度計測量牙齒表面，結果顯示本研究利用3%及5%新型乳酸磷酸鈣所備製之牙齒再礦化貼片，施用於去礦化牙齒之表面15 mins後，硬度恢復率分別為39.7 ± 39.1%及56.5 ± 43.8%，相較於人工唾液控制組之-12.2 ± 19.2%，可快速效促進牙齒再礦化，效果有顯著差異(p < 0.05 by paired t-test)。此外，若將CLP的再礦化能力運用於牙本質小管封填的領域，在先期測試中發現，添加CLP的膏劑比起市售的牙本質小管封填膏劑更加持久並能進一步使牙本質小管進一步縮小。研究結果證實將CLP運用於牙齒再礦化之可行性。 |
