Xu H H K, Weir M D, Sun L, Takagi S, Chow L C
Paffenbarger Research Center, American Dental Association Foundation, National Institute of Standards and Technology, Building 224, Room A-153, Stop 8546, Gaithersburg, MD 20899-8546, USA.
J Dent Res. 2007 Apr;86(4):378-83. doi: 10.1177/154405910708600415.
Nano-particles of dicalcium phosphate anhydrous (DCPA) were synthesized for the first time. The objectives of this study were to incorporate DCPA nano-particles into resin for Ca-PO(4) release to combat dental caries, and to investigate the filler level effects. Nano-DCPA and nano-silica-fused silicon nitride whiskers at a 1:1 ratio were used at filler mass fractions of 0-75%. The flexural strengths in MPa (mean +/- SD; n = 6) of DCPA-whisker composites ranged from (106 +/- 39) at 0% fillers to (114 +/- 23) at 75% fillers, similar to (112 +/- 22) of a non-releasing composite (TPH) (p > 0.1). The composite with 75% fillers in a NaCl solution (133 mmol/L, pH = 7.4, 37 degrees C) yielded a Ca concentration of (0.65 +/- 0.02) mmol/L and PO(4) of (2.29 +/- 0.07) mmol/L. Relationships were established between ion-release and DCPA volume fraction V(DCPA): Ca = 4.46 V(DCPA)(1.6,) and = 66.9 V(DCPA)(2.6). Nano-DCPA-whisker PO(4) composites had high strength and released high levels of Ca-PO(4) requisite for remineralization. These new nano-composites could provide the needed combination of stress-bearing and caries-inhibiting capabilities.
首次合成了无水磷酸二钙（DCPA）纳米颗粒。本研究的目的是将DCPA纳米颗粒掺入树脂中以实现钙-磷酸盐（Ca-PO₄）释放来防治龋齿，并研究填料含量的影响。以1:1比例使用纳米DCPA和纳米二氧化硅-氮化硅晶须，填料质量分数为0-75%。DCPA-晶须复合材料的弯曲强度（单位为MPa，均值±标准差；n = 6）范围从0%填料时的（106±39）到75%填料时的（114±23），与非释放型复合材料（TPH）的（112±22）相似（p>0.1）。在NaCl溶液（133 mmol/L，pH = 7.4，37℃）中含有75%填料的复合材料产生的Ca浓度为（0.65±0.02）mmol/L，PO₄浓度为（2.29±0.07）mmol/L。建立了离子释放与DCPA体积分数V(DCPA)之间的关系：Ca = 4.46 V(DCPA)¹·⁶，PO₄ = 66.9 V(DCPA)²·⁶。纳米DCPA-晶须PO₄复合材料具有高强度，并释放出再矿化所需的高水平Ca-PO₄。这些新型纳米复合材料可提供所需的承载应力和抑制龋齿能力的组合。
