[Metal-ceramic bond strength of Co-Cr alloy processed by selective laser melting]

To evaluate the metal-ceramic bond strength of a selective laser melting Co-Cr alloy.

Twelve Co-Cr metal bars were prepared according to the ISO 9693 standard with Vita porcelain fused onto the centre of each bar. Then the sample bars were divided into two groups of six each. The control group was made by traditional cast process (cast group), and the experimental group was processed by selective laser melting (SLM) technology (SLM group). Metal-ceramic bonding strength and fracture mode were assessed using three-point bending test. Fracture mode analysis was determined by scanning electronic microscope/energy dispersive spectroscopy. Student's t-test was used to analyze the data in SPSS 13.0.

The metal-ceramic bond strength value of the cast group was (33.45 ± 2.34) MPa, and that of the SLM group was (31.62 ± 2.34) MPa (t = 0.79, P > 0.05). A mixed fracture mode on the debonding interface of all specimens was observed, while little porcelain was reserved.

The metal-ceramic system processed by SLM exhibited a bonding strength that satisfies the requirement of clinical application.