Surface Roughness of Ceramic Implant Abutments Prepared with Diamond Burs

Objective: To evaluate and compare the surface roughness of ceramic implant abutments (aluminum oxide and zirconium oxide) prepared with various diamond burs. Methods: A cutting regimen with a KaVo highspeed handpiece, 25 ml/min water spray and a 102.1g load at the bur interface was used to section blocks of aluminum oxide provided by Nobel Biocare and zirconium oxides provided by Nobel Biocare and 3i. Eight types of diamond burs from different companies were used to section 4 mm x 4 mm of each block six times. The surface roughness (Ra value) was measured using a surface profilometer (Mitutoyo Surftest SV-514), both parallel and perpendicular to the cut surfaces (four Ra values were recorded: Start and End of the cut surface and the surface cut by the Shank and Tip of the diamond bur). The data was analyzed with a one-way ANOVA followed by Tukey HSD Test to determine statistical differences between groups. Results: For Nobel Biocare zirconium oxide, only the Axis 856C bur produced a significantly smoother surface finish most consistently (Start F=2.80, p=0.01; Shank F=5.644, p=0.0001; Tip F=4.042, p=0.001). For 3i zirconium oxide, three types of diamond burs (Axis 856 TSC, Brasseler 2856, Brasseler 6856) produced a significantly smoother surface finish on the Shank and Tip but not on the Start and End (F= 4.09, 4.681 with p=0.001, 0.0001, respectively). There was no significant difference in surface roughness of Nobel Biocare aluminum oxide with any of the burs. Conclusion: For the Nobel Biocare zirconium oxide implant abutment, the smoothest surface can be obtained with an Axis 856C bur. Axis 856 TSC, Brasseler 2856,and Brasseler 6856 burs are best recommended for preparation of 3i zirconium oxide implant abutment. For Nobel Biocare aluminum oxide implant abutment, all diamond burs produced a similar surface finish.