@article { author = {Madani, Azamsadat and Ghahremanlu, Ahmad and Sabooni, Mohammad Reza and Shahabian, Foad and Harati, Hamzeh}, title = {The Effect of Bridge Orientation in Casting Machine on the Castability and Quality of Base Metal Castings}, journal = {Journal of Dental Materials and Techniques}, volume = {1}, number = {2}, pages = {53-57}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2322-4150}, eissn = {2252-0317}, doi = {10.22038/jdmt.2013.94}, abstract = {Introduction: The aim of this study was to evaluate the effect of bridge orientation in casting machine on castability and quality of base metal castings. Methods: Three groups of patterns with different direction and lengths in casting machine were casted and then studied qualitatively and quantitatively using mean and standard deviation in table of frequency. Results: Larger nodules and porosities were on the joints of sprue in horizontal specimens (P=0.01 and 0.048, respectively). There was no significant difference in castability between 3-, 5- and 6-unit bridges in relation to their direction in casting machine (P=0.5). An increase in bridge length led to more variation in length and width. The position of bridges also played an important role in the length variation in bridges. Conclusion: The direction of bridges had no effect on base metal castability but a vertical position resulted in a better casting quality and an increase in length of the bridges caused more defects in castings.}, keywords = {Base metal,casting machine,dental casting technique}, url = {https://jdmt.mums.ac.ir/article_94.html}, eprint = {https://jdmt.mums.ac.ir/article_94_d8f1dbf77a1de3c69ed73060b593287f.pdf} }