Fleming Garry J P, Kenny Sinead M, Barralet Jake E
Biomaterials Unit, University of Birmingham School of Dentistry, St. Chad's Queensway, Birmingham B4 6NN, UK.
J Dent. 2006 Feb;34(2):155-63. doi: 10.1016/j.jdent.2005.05.008. Epub 2005 Aug 8.
An optimisation of the mixing ratio of an encapsulated glass-ionomer restorative in terms of compressive strength, working characteristics and pore distribution following mechanical mixing with different mixing machines was undertaken.
Mean compressive fracture strengths, standard deviations and associated Weibull Moduli (m) were determined from series of 30 encapsulated specimens with varying powder/liquid mixing ratios. Working characteristics were assessed using an oscillating rheometer and scanning electron microscopy and image analysis was used to investigate the influence of the mixing ratios and mixing regime on the pore distribution.
Cement mixing regime or reducing the powder/liquid mixing ratio did not have any significant influence on the compressive strength. Utilising the one-way ANOVA and Tukey test comparisons at P<0.05 the cement manipulation regime significantly increased the compressive strength on increasing the powder content of the capsule by 10% (G110) when a combination of rotational and centrifugal action rather than vibration were employed. Utilising a Rotomix at a powder content of G110 was beneficial in reducing porosity levels within the restorative investigated compared with a conventional mixing machine. Increasing the powder content reduced the working characteristics regardless of the mixing regime.
The increased reliability of encapsulated restoratives reported in the literature following mixing with a combination of rotational and centrifugal compared with vibrational action was only evident when the powder content of the restorative under investigation was increased by 10%. The finding suggests that the initial viscosity of the cement mass of the Ketac Fil Plus Aplicap as supplied by the manufacturer may not have been optimised.
通过使用不同的混合机进行机械混合，对封装型玻璃离子修复材料的混合比例在抗压强度、工作特性和孔隙分布方面进行优化。
从30个具有不同粉液混合比例的封装样本系列中确定平均压缩断裂强度、标准差和相关的威布尔模量（m）。使用振荡流变仪评估工作特性，并通过扫描电子显微镜进行评估，同时利用图像分析研究混合比例和混合方式对孔隙分布的影响。
水泥混合方式或降低粉液混合比例对抗压强度没有显著影响。在P<0.05水平下，使用单向方差分析和Tukey检验比较发现，当采用旋转和离心作用而非振动的组合时，将胶囊中的粉末含量增加10%（G110），水泥操作方式会显著提高抗压强度。与传统混合机相比，使用粉末含量为G110的Rotomix有利于降低所研究修复材料内的孔隙率水平。无论混合方式如何，增加粉末含量都会降低工作特性。
与振动作用相比，文献报道的在采用旋转和离心组合混合后封装修复材料的可靠性提高，仅在所研究修复材料的粉末含量增加10%时才明显。这一发现表明，制造商提供的Ketac Fil Plus Aplicap水泥团块的初始粘度可能未得到优化。
