Guttal Satyabodh S, Patil Narendra P
Department of Prosthodontics, SDM College of Dental Sciences and Hospital, Dharwad, Karnataka, India.
Quintessence Int. 2007 Feb;38(2):e78-82.
The aim of the study was to evaluate the pure titanium castability and internal porosity with 3 different sprue designs.
The sprue designs selected were the conventional cylindrical, funnel-shaped, and sheet-form sprue formers. To evaluate the castability, the mesh monitor was chosen. Eight mesh patterns (14 3 14 mm) of 49 squares were attached to each type of sprue design. They were invested in titanium investment material and cast in a semiautomatic titanium casting machine. The titanium castings were evaluated by 2 methods. One was the visual observation of the castings for completeness, and the second was the radiographic qualitative analysis for the location of the internal porosities.
Data were analyzed with analysis of variance and Student t test for paired comparison among different sprue designs. According to analysis of variance, all sprue designs revealed a statistically significant difference at the 5% level of confidence (P <.05, F = 3.50). Mesh patterns attached to funnel-shaped sprue designs showed better percentage castability values.
For titanium, casting using a funnel-shaped sprue design displayed better castability values and less internal porosities in the castings.
本研究的目的是评估3种不同浇道设计的纯钛铸造性能和内部孔隙率。
所选的浇道设计为传统圆柱形、漏斗形和片状浇道成型器。为评估铸造性能，选用了网格监测器。在每种浇道设计上附着8个由49个正方形组成的网格图案（14×3×14毫米）。将它们用钛铸造包埋材料包埋，并在半自动钛铸造机中铸造。通过两种方法对钛铸件进行评估。一种是对铸件的完整性进行目视观察，另一种是对内部孔隙位置进行射线照相定性分析。
采用方差分析和学生t检验对不同浇道设计之间的数据进行配对比较分析。根据方差分析，在5%的置信水平下，所有浇道设计均显示出统计学上的显著差异（P<.05，F=3.50）。附着在漏斗形浇道设计上的网格图案显示出更好的铸造成功率百分比值。
对于钛，采用漏斗形浇道设计进行铸造时，铸件具有更好的铸造性能和更少的内部孔隙。
