Laboratory of Biomaterials and Oral Pathology, Department of Odontostomatological Sciences, University of Bologna, Via San Vitale 59, 40125 Bologna, Italy.
Dent Mater. 2011 Jul;27(7):e134-57. doi: 10.1016/j.dental.2011.03.011. Epub 2011 May 6.
An innovative light-curable calcium-silicate cement containing a HEMA-TEGDMA-based resin (lc-MTA) was designed to obtain a bioactive fast setting root-end filling and root repair material.
lc-MTA was tested for setting time, solubility, water absorption, calcium release, alkalinizing activity (pH of soaking water), bioactivity (apatite-forming ability) and cell growth-proliferation. The apatite-forming ability was investigated by micro-Raman, ATR-FTIR and ESEM/EDX after immersion at 37°C for 1-28 days in DPBS or DMEM+FBS. The marginal adaptation of cement in root-end cavities of extracted teeth was assessed by ESEM/EDX, and the viability of Saos-2 cell on cements was evaluated.
lc-MTA demonstrated a rapid setting time (2min), low solubility, high calcium release (150-200ppm) and alkalinizing power (pH 10-12). lc-MTA proved the formation of bone-like apatite spherulites just after 1 day. Apatite precipitates completely filled the interface porosities and created a perfect marginal adaptation. lc-MTA allowed Saos-2 cell viability and growth and no compromising toxicity was exerted.
HEMA-TEGDMA creates a polymeric network able to stabilize the outer surface of the cement and a hydrophilic matrix permeable enough to allow water absorption. SiO(-)/Si-OH groups from the mineral particles induce heterogeneous nucleation of apatite by sorption of calcium and phosphate ions. Oxygen-containing groups from poly-HEMA-TEGDMA provide additional apatite nucleating sites through the formation of calcium chelates. The strong novelty was that the combination of a hydraulic calcium-silicate powder and a poly-HEMA-TEGDMA hydrophilic resin creates the conditions (calcium release and functional groups able to chelate Ca ions) for a bioactive fast setting light-curable material for clinical applications in dental and maxillofacial surgery. The first and unique/exclusive light-curable calcium-silicate MTA cement for endodontics and root-end application was created, with a potential strong impact on surgical procedures.
本研究设计了一种含有 HEMA-TEGDMA 基树脂的新型光固化硅酸钙水泥（lc-MTA），旨在获得一种具有生物活性的快速凝固根管填充和根管修复材料。
对 lc-MTA 的凝固时间、溶解度、吸水率、钙释放、碱化活性（浸出液 pH 值）、生物活性（形成磷灰石的能力）和细胞生长增殖进行了测试。将浸提牙根管内的水泥在 DPBS 或 DMEM+FBS 中于 37°C 下分别浸泡 1-28 天后，通过微拉曼、ATR-FTIR 和 ESEM/EDX 研究其磷灰石形成能力。通过 ESEM/EDX 评估水泥在牙根管内的边缘适应性，通过 Saos-2 细胞评价水泥的细胞活力。
lc-MTA 表现出快速凝固时间（2 分钟）、低溶解度、高钙释放（150-200ppm）和碱化能力（pH 10-12）。lc-MTA 在第 1 天即可形成骨样磷灰石球晶。磷灰石沉淀物完全填充界面孔隙，实现了完美的边缘适应性。lc-MTA 允许 Saos-2 细胞存活和生长，且没有产生有害毒性。
HEMA-TEGDMA 形成了一种聚合物网络，能够稳定水泥的外表面，并形成具有足够亲水性的基质，允许水吸收。来自矿物颗粒的 SiO(-)/Si-OH 基团通过钙和磷酸盐离子的吸附诱导磷灰石的异质成核。来自聚 HEMA-TEGDMA 的含氧基团通过形成钙螯合物提供额外的磷灰石成核位点。其创新性在于，水硬性硅酸钙粉末和聚 HEMA-TEGDMA 亲水树脂的结合为临床应用于牙科和颌面外科的生物活性快速凝固光固化材料创造了条件（钙释放和能够螯合 Ca 离子的功能基团）。研发出了首款独特的光固化硅酸钙 MTA 牙胶用于根管和根尖应用，可能会对手术过程产生重大影响。
