Revista de Odontologia da UNESP
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Revista de Odontologia da UNESP
Original Article

Expansão de um revestimento incluído em função do tempo de aplicação do revestimento de cobertura

Expansion of an invested investment as a fuction of the application time of the coverture investment

Bombonatti, P.E.; Garlipp, O.A.

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Resumo

Verificou-se a expansão de um revestimento em função do tempo de vazamento de uma segunda mistura sobre o mesmo. As alterações dimensionais do revestimento interno foram verificadas através de um microscópio de mensuração. Determinou-se que a expansão de presa do revestimento interno é afetada ao ser coberto por outro revestimento, encontrando-se maiores valores quando a aplicação é feita no momento da sua presa

Palavras-chave

Revestimento, inclusão, expansão de presa

Abstract

The purpose of this work was to verify the influence of pouring time variation of the second mixture of investment on the inner investment expansion, when the double investing technique is employled. The dimensional changes of the inner investment was measured through the use of a Carl Zeiss microscope, 00,1mm precise. A shield of acrylic resin was made on a glass slab and 50 mm from it a slider transmited the dimensional changes. The shield and one end of the slider were covered with investment. the second mixture of investment was poured 5 minutes before the setting time, during the setting time and 5, 10, 15 Jand 20 minutes after the setting time of first mixture. The analysis of variance allowed us to conclude that: 1) the expansion that follows the setting reaction of the investment is affected by the second pouring of investment: 2) this expansion depends on the time of pouring the second mixture of investment; the highest values occur when the second mixture is poured during the setting time of the first one; 3) all the values obtained are higher in relation to the setting expansion and lower to the hygroscopic expansion of the first mixture of investment; 4) a half an hour should be allowed before pouring the second mixture to avoid an exagerated influence on the expansion of the first mixture.

Keywords

Revestimento, inclusão, expansão de presa

References



BOWNLEE, K. A. 1953. Industrial Experimentation · Chemical Co. Inc. New York.

CRAIG, R. G., ANTHONY, D. G. & PEYTON, F. A. 1961. Dimensional changes in duplicated investments casts. Dent. Progr., S:35-A5.

GARLIPP, O.A. & BOMBONATTI, P.E. 19/9. Expasão de um revestimento incluído no momento de sua presa, em função do tempo de presa do revestimento de cobertura. Da. dos em publicação.

HOLLENBACK, G. M. 1943. Precision goId inlays made by a simple tecnic. J. Amer. dento Ass., 30:99109. HüLST, K. 1961. Utilsigtet hygroskopik ekspasion i gips og indsobningsm~ sse. Tandlaegeblated, 65:163-168.

MATSUMOTO, A. H. 1979. Inclusão de padrão de cera para fundição. Prótese Dentária, 43:4 e 11. Rev. Odont. UNESP 1979/1980 - vol. 8/9

PEYTON, F. A. & CRAIG, R. G. 1971. Restorative Dental MateriaIs. 4th ed., C. V. Mosby Co., Saint Louis.

PEYTON, F.A., MAHLER, D.B. & ASGAR, K. 1956. Control1ed wateraddition technique for hygroscopic expansion of dental casting investment. J. Amer. dent. Ass., 52: 155161.

SHELL, J. S. 1958. Setting and thermaI expansion of investments: Part II. Effects of changes in water/powder ratio, dry vs. wet liners and liner short on one end of ring on1y. J. Alabama dent. Ass., 52:22-25,
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