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The Fit of Gold-alloy Full-crown Castings Made with Pre-wetted Casting Ring Liners
E.F. Morey
R. Earnshaw
Department of Prosthetic Dentistry, University of Sydney, 2 Chalmers Street, Surry Hills, NSW, Australia 2010
Measurements were made of the fit of full-crown gold-alloy castings produced with two types of pre-wetted ring liner (asbestos and cellulose) and a typical gypsum-bonded investment (Cristobalite Inlay, Sybron/Kerr Products, Romulus, MI; W/P = 0.40). Laboratory measurements were made of the effects of the liners on potential investment expansion, and properties of the lining materials considered relevant to casting accuracy were also measured.
There was a wide variation in values for mean dimensional inaccuracy. One liner produced a series of castings all of whose inaccuracies lay within the range ± 0.1%, with a mean value of + 0.01%. With the other five liners, all or most castings were undersize. With three, all or most castings showed inaccuracies worse than -0.2%.
The values for casting inaccuracy with the various liners showed a probable correlation with potential investment expansion (p < 0.05); however, no correlation was found between casting inaccuracy and any apparently relevant liner properties, alone or in combination. In casting techniques which use a pre-wetted ring liner, the choice of a specific lining material is an important factor which has a significant effect on casting inaccuracy. With at least three of the six liners tested, a higher investment expansion was needed for accurate full-crown castings to be ensured.
REFERENCES
- Coleman RL (1928). Physical properties of dental materials. Bur Stand JRes 1:867-938.
- Davis DR (1987). Limiting wax pattern distortion caused by setting expansion. J Prosthet Dent 58:229-234.[CrossRef][Medline]
[Order article via Infotrieve]
- Davis DR (1989). Effect of investment mass on distortion of MOD wax patterns. Dent Mater 5:93-96.[CrossRef][Medline]
[Order article via Infotrieve]
- Earnshaw R. (1958). The casting shrinkage of cobalt-chromium alloys. Aust Dent J 3:159-170.[Medline]
[Order article via Infotrieve]
- Earnshaw R. (1969). The effect of restrictive stress on the hygroscopic setting expansion of gypsum-bonded investments. Aust Dent J 14:22-29.[Medline]
[Order article via Infotrieve]
- Earnshaw R. (1988). The effect of casting ring liners on the potential expansion of a gypsum-bonded investment. J Dent Res 67:1366-1370.[Abstract/Free Full Text]
- Earnshaw R., Marks BI (1964). The measurement of setting time of gypsum products. Aust Dent J 9:17-26.[CrossRef]
- Eden GT, Franklin OM, Powell JM, Ohtay, Dickson G. (1979). Fit of porcelain fused-to-metal crown and bridge castings. J Dent Res 58:2360-2368.[Abstract/Free Full Text]
- Finger W., Jørgensen KD (1980). An improved dental casting investment. Scand J Dent Res 88:278-284.[Medline]
[Order article via Infotrieve]
- Gil L., Moore BK, Dykema R. (1982). Fit of full crowns using three ring liner materials (abstract). J Dent Res 61:344.
- Herbert WE, Thompson ARF (1934). A practical comparison of modern gold inlay techniques. Br Dent J 57:184-197.
- Jørgensen KD (1953). Investigations of dental precision casting technic. Göteborgs Tandläkare-Sallskäps 236:1-45.
- Khatchaturian Z., Caputo AA (1982). Accuracy of castings using non-asbestos casting ring liners (abstract). J Dent Res 61:330.
- Kozono Y. (1977). Effect of the core on fitness of dental castings. J Kyushu Dent Soc 31:154-169.
- Mahler DB, Ady AB (1963). The influence of various factors on the effective setting expansion of casting investments. J Prosthet Dent 13:365-373.[Medline]
[Order article via Infotrieve]
- Mumford G., Phillips RW (1958). Dimensional change in wax patterns during setting of gypsum investments. J Dent Res 37:351-358.[Free Full Text]
- Nagasawa S., Ito M., Takahashi S., Suzuki Y., Amano K. (1975). Studies on the accuracy ofthe casts, Part III. Shikwa Gakuho 75:286-292 (in Japanese).[Medline]
[Order article via Infotrieve]
- Nasu T., Noguchi H. (1982). The cushion ability of lining materials for the setting and heating expansion of plaster bonded investment in the casting ring. Jpn J Dent Mater Apparatus 23:65-75 (in Japanese).
- Priest G., Horner JA (1980). Fibrous ceramic aluminum silicate as an alternative to asbestos liners. J Prosthet Dent 44:51-56.[CrossRef][Medline]
[Order article via Infotrieve]
- Scheu CH (1933). Precision casting utilizing the hygroscopic action of plaster in investment in making expanded molds. J Am Dent Assoc 20:1205-1215.
- Scheu CH (1935). Controlled hygroscopic expansion of investment to compensate for shrinkage in inlay casting. J Am Dent Assoc 22:452-455.
- Steinbock DJ, Asgar K. (1978). A possible substitute for asbestos as a casting ring lining material (abstract). J Dent Res 57:255.[Abstract/Free Full Text]
- Suffert LW, Mahler DB (1955). Reproducibility of gold castings made by present day dental casting technics. J Am Dent Assoc 50:1-6.[Medline]
[Order article via Infotrieve]
- Teteruck WR, Mumford G. (1966). The fit of certain dental casting alloys using different investing materials and techniques. J Prosthet Dent 16:910-927.[CrossRef][Medline]
[Order article via Infotrieve]
- van Aken J. (1961). Distortion of wax patterns as influenced by setting and hygroscopic expansion of the investment. Tijdschr Tandheelk 68:583-610.
- Warfield DK, Lipson SW, Priest GF (1982). Relative casting accuracies using asbestos and non-asbestos liners (abstract). J Dent Res 61:186.
- Yli-Urpo A., 0ilo G., Syverud M. (1982). The effect of asbest- alternatives on the accuracy of cast veneer crowns. Swed Dent J 6:127-131.[Medline]
[Order article via Infotrieve]
Journal of Dental Research, Vol. 71, No. 12,
1858-1864 (1992)
DOI: 10.1177/00220345920710120101

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