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[Experimental study of the effect on marginal seating of the castings by different investing methods]
Wei-shan Ding1, Ai-ling Huang, Yan-ying Zhang
1School of Dentistry, Shandong University, Jinan 250012, China.
Objective:
The purpose of this study was to observe the effect on marginal seating of the castings with and without ring investments.
Methods:
Standarded as-cast specimens and round capsules simulated post tooth crowns were made. 12 wax pattern were prepared on the as-cast specimens. The 12 specimens were divided into two groups with 6 wax pattern in each group. Two different investing methods with the same investing material were tested. The marginal seating of the castings was measured under travelling microscope.
Results:
The marginal seating of the casting without ring investment had significant difference compared with the castings with ring investment (P<0.05).
Conclusion:
Casting without ring can improve the marginal seating of the castings.
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