Selective laser melted CoCr alloy - biocompatibility

    The computer assisted design for dental prosthetics has allow a precise and easy control of design process (undercuts blocking, precise insertion axis, etc) and the final dental prosthetic restorations are consistent with the patient case (of course, this is dependent on the correct impression and/or 3D scan)
    The advantages of additive manufacturing process are the short time needed to manufacture the custom part, repeatability and traceability of the manufacturing process (by eliminating the variations that arise in the LWC manufacturing process).
    The selective laser melting process is an additive manufacturing process, where the parts are constructed layer by layer in the 3D shape, based on the CAD file, directly from the alloy chosen without additional binder agent use.

    The parts from Co-Cr alloy manufactured by selective laser melting process have the density of 99.9%, without porosity, high hardness, high yield strength, are biocompatible and they meet the geometry of the 3D CAD designed part. (reference 1)

Selective laser melted CoCr alloy - biocompatibility

    Based on test made with fibroblast l929 cellular media (method: MTT (3 - (4,5-ddimethylthiazol-2-il) -2,5-diphenyltetrazolium; ADT agar test; DET test), a viability rate of 99% in 24 hours, have been observed. Selective laser melted Co Cr alloy structures are ranked as non-cytotoxic, according ISO standards. (reference 2)

    The test ware done in accordance with EN ISO 10271:2011 (Dentistry - Corrosion test methods for metallic materials) - artificial saliva and lactic acid immersion, measurement done by mass absorption spectrophotometry and in accordance with ISO 22674:2006 (Dentistry. Metallic materials for fixed and removable restorations and appliances) - "in vitro" ion realise; in addition to cytotoxicity study (Jevremović et al., 2011). (reference 3)
    Based on this tests, a low and secure level of ion emission has been observed for Cr, Co and Mo (in accordance with ISO issued limits). Also the parts manufactured by selective laser melting method performs better then the parts done by LWC method. (reference 3)

The alloy that we use for dental reconstruction prosthesis is comprised of 59.0% Co; 25.0% Cr; 9.5% W; 3.5% Mo; max 1% Si, max 1.5% C,Fe,Mn,N (without Ni and Be) and is biocompatible.

    The Co-Cr alloy that we use, is in compliance with the following standards:

DIN EN ISO 14971:2009 Medical devices. Application of risk management to medical devices
DIN EN ISO 22674:2007 Dentistry - Metallic materials for fixed and removable restorations and appliances
DIN EN ISO 980:2008 Symbols for use in the labelling of medical devices
DIN EN ISO 1641:2009 Dentistry. Medical devices for dentistry. Materials
DIN EN ISO 9693:2000 Metal-ceramic dental restorative systems