Dental casting alloys: technical and economic considerations in the USA.
In the USA, gold alloys have played a prominent role in oral health maintenance for more than 100 years. Recently, however, a marked trend toward substitution of palladium-silver and nickel-chromium based materials for the more costly gold alloys has been observed. It is estimated that 60-80 per cent of all permanent dental appliances (crowns and bridges) are now fabricated from non-gold alloys. For the most part, increased user demand for alloy products of relatively low intrinsic value has affected adversely the profitability of the larger USA casting alloy suppliers. The likelihood of a reversal of the trend occurring during the 1980s is not great. All major USA dental alloy manufacturers have found it necessary to market an ever increasing spectrum of low cost alloy products. Impetus for this production of a new generation of dental casting alloys has risen mainly from the perceived purchasing patterns of current and future customers. It is anticipated that the 'down-grading' of dental casting alloys will continue until plastics, mouldable ceramics or other inexpensive industrial materials replace metals in the fabrication of permanently cemented dental devices. Until then, it is likely that gold alloys will remain the ultimate prosthetic materials in the minds of dental academicians while technique-sensitive and unproved metallic products of low intrinsic value will continue to gain greater acceptance by practising dentists, laboratory technicians and patients.