Comparison of Dental Prostheses Cast and Sintered by SLM from Co-Cr-Mo-W Alloy

Abstract

The article presents the results of a comparative analysis of the metal substructure for dental prosthesis made from a Co-Cr-Mo-W alloy by two techniques, i.e. precision investment casting and selective laser melting (SLM). It was found that the roughness of the raw surface of the SLM sinter is higher than the roughness of the cast surface, which is compensated by the process of blast cleaning during metal preparation for the application of a layer of porcelain. Castings have a dendritic structure, while SLM sinters are characterized by a compact, fine-grain microstructure of the hardness higher by about 100 HV units. High performance and high costs of implementation the SLM technology are the cause to use it for the purpose of many dental manufacturers under outsourcing rules. The result is a reduction in manufacturing costs of the product associated with dental work time necessary to scan, designing and treatment of sinter compared with the time needed to develop a substructure in wax, absorption in the refractory mass, casting, sand blasting and finishing. As a result of market competition and low cost of materials, sinter costs decrease which brings the total costs related to the construction unit making using the traditional method of casting, at far less commitment of time and greater predictability and consistent sinter quality.

Selective laser melting and sintering technique of the cobalt-chromium dental alloy

“…Relevant data found in the literature indicate that the average surface roughness (the profile roughness parameter) immediately after sintering is about 8 μm [27]. After sand-blasting Al 2 O 3 , the roughness is reduced due to surface homogenization and uniformization.…”

The Marginal and Internal Fit of Cocr Alloy Single Crowns With Preparation Designs Including Auxiliary Features; Cad/Cam Versus Conventional Technique

“…Mnoho studií hodnotilo vhodnost SLM sintrování, frézování a lití pro zhotovení korunek a můstků z dentálních slitin [7,15,19,[24][25][26][27][28][29][30][31][32][33][34][35]. Autoři své studie uzavírali tak, že přesnost dosedu náhrad vyrobených SLM sintrováním a/ nebo frézováním byla podobná litým náhradám, a tudíž že současné CAD/CAM technologie mohou být považovány za možnou alternativu tradiční licí techniky [14,15,19,25,27,[30][31][32]34].…”

“…Autoři své studie uzavírali tak, že přesnost dosedu náhrad vyrobených SLM sintrováním a/ nebo frézováním byla podobná litým náhradám, a tudíž že současné CAD/CAM technologie mohou být považovány za možnou alternativu tradiční licí techniky [14,15,19,25,27,[30][31][32]34]. Zmíněné studie se však zabývaly pouze standardním způsobem preparace pahýlu [7,15,19,22,[24][25][26][27][28][29][30][31][32][33][34][35]. Přestože používání CAD/CAM technologií se v zubním lékařství podstatně rozšířilo [5][6][7], existuje jen málo informací o tom, jak moc jsou CAD/CAM systémy schopné vytvořit složité vnitřní povrchy korunek odpovídající tvaru povrchu preparovaného pahýlu obsahujícího pomocné retenční prvky, jako kavity nebo sloty.…”

Thin Films Deposition of Ta2O5 and ZnO by E-Gun Technology on Co-Cr Alloy Manufactured by Direct Metal Laser Sintering

“…Direct metal laser sintering technology can be used not only in medicine, but also in aerospace, aeronautics, automotive, and electronic industrial domains. In medicine, the DMLS process is successfully used for manufacturing dental restorations, such as dental crowns, bridges, and chapels [11][12][13][14][15][16]. The Co-Cr alloy powder used in the DMLS process presents good engineering properties as well as good corrosion resistance [17,18].…”