Wedekind Lennart, Güth Jan-Frederik, Schweiger Josef, Kollmuss Maximilian, Reichl Franz-Xaver, Edelhoff Daniel, Högg Christof
Department of Prosthetic Dentistry, University Hospital, LMU Munich, Germany.
Department of Prosthetic Dentistry, University Hospital, LMU Munich, Germany; Department of Prosthodontics, Center for Dentistry and Oral Medicine (Carolinum), Goethe-University Frankfurt am Main.
Dent Mater. 2021 Apr;37(4):701-710. doi: 10.1016/j.dental.2021.01.024. Epub 2021 Feb 27.
The elution of unpolymerized (co-)monomers and additives from methacrylic resin-based materials like polymethyl methacrylate (PMMA) can cause adverse side effects, such as mutagenicity, teratogenicity, genotoxicity, cytotoxicity and estrogenic activity. The aim of this study was to quantify the release and the cytotoxicity of residual (co-)monomers and additives from PMMA-based splint materials under consideration of real splint sizes. Three different materials used for additive (3D printing), subtractive (milling) and conventional (powder and liquid) manufacturing were examined.
The splint materials SHERAprint-ortho plus (additive), SHERAeco-disc PM20 (subtractive) and SHERAORTHOMER (conventional) were analysed. 16 (n = 4) sample discs of each material (6 mm diameter and 2 mm height) were polished on the circular and one cross-section area and then eluted in both distilled water and methanol. The discs were incubated at 37 °C for 24 h or 72 h and subsequently analysed by gas chromatography/mass spectrometry (GC/MS) for specifying and quantifying released compounds. XTT-based cell viability assays with human gingival fibroblasts (HGFs) were performed for Tetrahydrofurfuryl methacrylate (THFMA), 1,4-Butylene glycol dimethacrylate (BDDMA) and Tripropylenglycol diacrylate (TPGDA). In order to project the disc size to actual splint sizes in a worst-case scenario, lower and upper jaw occlusal splints were designed and volumes and surfaces were measured.
For SHERAeco-disc PM20 and for SHERAORTHOMER no elution was determined in water. SHERAprint-ortho plus eluted the highest THFMA concentration of 7.47 μmol/l ±2,77 μmol/l after 72 h in water. Six (co-)monomers and five additives were detected in the methanol eluates of all three materials tested. The XTT-based cell viability assays resulted in a EC of 3006 ± 408 μmol/l for THFMA, 2569.5 ± 308 μmol/l for BDDMA and 596.7 ± 88 μmol/l for TPGDA.
With the solvent methanol, released components from the investigated splint materials exceeded cytotoxic concentrations in HGFs calculated for a worst-case scenario in splint size. In the water eluates only the methacrylate THFMA could be determined from SHERAprint-ortho plus in concentrations below cytotoxic levels in HGFs.
未聚合的（共）单体和添加剂从聚甲基丙烯酸甲酯（PMMA）等甲基丙烯酸树脂基材料中洗脱出来可能会引起不良副作用，如致突变性、致畸性、遗传毒性、细胞毒性和雌激素活性。本研究的目的是在考虑实际夹板尺寸的情况下，对基于PMMA的夹板材料中残留的（共）单体和添加剂的释放量及细胞毒性进行定量分析。研究了用于增材制造（3D打印）、减材制造（铣削）和传统制造（粉末和液体）的三种不同材料。
对夹板材料SHERAprint-ortho plus（增材制造）、SHERAeco-disc PM20（减材制造）和SHERAORTHOMER（传统制造）进行分析。每种材料取16个（n = 4）样品盘（直径6 mm，高2 mm），在圆形和一个横截面上进行抛光，然后分别在蒸馏水和甲醇中洗脱。将样品盘在37℃下孵育24小时或72小时，随后通过气相色谱/质谱联用仪（GC/MS）分析以确定和定量释放的化合物。对甲基丙烯酸四氢糠酯（THFMA）、1,4-丁二醇二甲基丙烯酸酯（BDDMA）和三丙二醇二丙烯酸酯（TPGDA）进行基于XTT的人牙龈成纤维细胞（HGF）细胞活力测定。为了在最坏情况下将样品盘尺寸推算至实际夹板尺寸，设计了上下颌咬合夹板并测量其体积和表面积。
对于SHERAeco-disc PM20和SHERAORTHOMER，在水中未检测到洗脱物。SHERAprint-ortho plus在水中孵育72小时后洗脱的THFMA浓度最高，为7.47 μmol/l ±2.77 μmol/l。在测试的所有三种材料的甲醇洗脱物中检测到六种（共）单体和五种添加剂。基于XTT的细胞活力测定结果显示，THFMA的半数有效浓度（EC）为3006 ± 408 μmol/l，BDDMA为2569.5 ± 308 μmol/l，TPGDA为596.7 ± 88 μmol/l。
使用溶剂甲醇时，所研究夹板材料释放的成分在最坏情况下的夹板尺寸计算中超过了HGFs中的细胞毒性浓度。在水洗脱物中，仅从SHERAprint-ortho plus中检测到甲基丙烯酸酯THFMA，其浓度低于HGFs中的细胞毒性水平。
