Journal List > J Korean Acad Prosthodont > v.51(4) > 1034754

Seo, Oh, Lee, Shin, Kim, and Park: Effect of different pattern size and pattern shape on castability of commercially pure titanium

Abstract

Purpose

The purpose of this study was to investigate the effect of geometrically different wax pattern shapes and sizes on the castability of Grade2 Cp-Ti (commercially pure titanium).

Materials and methods

Total of 40 mesh wax pattern (61 mm × 24 mm, 207 grids), (61 mm × 17 mm, 138 grids) was cast in this experiment. Depending on the geometrical shape of the wax pattern, 8 groups was organized; Flat, Semicircular, Horse-shoe and V-shape, each consisting 5 samples. Runner-bar sprue was used in all patterns. The number of completely cast grid in wax pattern served as a measure for the castability of comercially pure titanium.

Results

The mean value of square count in each group was as followed; 133.20 squares in group SS (96.52%), 132.40 squares in group SH (95.94%), 132.00 squares in group SF (95.65%), 127.60 squares in SV (91.43%), 198.60 squares in group LF (95.94%), 197.80 squares in group LV (95.56%), 196.40 squares in group LS (94.88%), and 188.00 squares in group LH (90.82%).

Conclusion

Within the limitations of this study the results indicate that there were no sttistically significant difference in castability of titanium regarding wax pattern shape (P>.05). However, Small size wax patterns were showing the noticeable castability more than Large size pattern. (J Korean Acad Prosthodont 2013;51:261-8)

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Fig. 1.
Schematic represntation of pattern size. A: Small, B: Large.
jkap-51-261f1.tif
Fig. 2.
Stone block indexes used for fabricating wax patterns. A: Semicircular, B: Horse-shoe, C: V-shape.
jkap-51-261f2.tif
Fig. 3.
Wax patterns of each group. A: Flat, B: Semicircular, C: Horse-shoe, D: V-shape.
jkap-51-261f3.tif
Fig. 4.
Preheating schedule of the invested molds.
jkap-51-261f4.tif
Fig. 5.
Titanium castability of shapes and size on the wax pattern.
jkap-51-261f5.tif
Fig. 6.
Sample of casted mesh patterns. A: Small Flat, B: Small Semicircular, C: Small Horse-shoe, D: Small V-shape, E: Large Flat, F: Large Semicircular, G: Large Horse-shoe, H: Large V-shape.
jkap-51-261f6.tif
Table 1.
Experimental groups used in this study
Pattern size Pattern design Code (n = 5)
Small (138 Grids) Flat SF
Semicircular SS
Horse-shoe SH
V-shape SV
Large (207 Grids) Flat LF
Semicircular LS
Horse-shoe LH
V-shape LV
Table 2.
Castability measurements of specimens
Group   N Mean SD Max Min Reproducibility (%)
SF   5 132.00 5.66 137 123 95.65
SS Small 5 133.20 3.96 138 128 96.52
SH (138 Grids) 5 132.40 3.51 138 129 95.94
SV   5 127.60 7.50 138 121 92.46
  Average   131.30 5.16 - - 95.14
LF   5 198.60 4.93 205 192 95.94
LS Large 5 196.40 6.58 205 187 94.88
LH (207 Grids) 5 188.00 14.32 201 169 90.82
LV   5 197.80 7.73 206 187 95.56
  Average   195.20 8.39 - - 94.30
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