Surface roughness and characteristics of CAD/CAM zirconia and glass ceramics after combined treatment procedures
Sibel Dikicier, Cumhur Korkmaz, Arzu Atay
Abstract
Abstract Background The roughening of the inner surface of a fixed ceramic restoration is an important factor for the bonding process. The aim of this study is to investigate the effect of combined surface treatments (acid etching, air-abrasion and Er: YAG Laser) on surface roughness of CAD/CAM fabricated zirconia (ZrO 2 ) and lithium-disilicate glass ceramics (LDS). Methods Sixty ZrO 2 (Ceramill Zi) and LDS (IPS e.max CAD) specimens, (5 mm in width, 5 mm in length and 1.5 mm in height) were fabricated using CAD/CAM and sintered according to the manufacturer’s instructions. All specimens subjected to three surface treatment combinations; etching with 4% hydrofluoric acide (HF), airborne-particle abrasion with 110-μm alumina (Al 2 O 3 ) (AP) and Er:YAG laser (Er:YAG) (Group A—HF + AP; Group B—Er:YAG + AP, and Group C—Er:YAG + HF). Perthometer was used to measure the surface roughness of the specimens before and after the tretments. Results Group A presented the highest Ra (LDS 0.81 ± 0.27 and ZrO 2 0.67 ± 0.21 after treatment) and Group C the lowest (LDS 0.45 ± 0.13 and ZrO 2 0.26 ± 0.07, after treatment). Compared with before treatment, the Ra were significantly different only in Group A both ZrO 2 and LDS after treatment ( p < 0.05). Qualitative SEM images suggested the surface topography of the ZrO 2 was smoother than the LDS. Less surface changes were observed in the Er:YAG combined procedures than HF + AP. Conclusions HF + AP was significantly succesful in modifying the ceramic surface. Er:YAG did not sufficiently promote the surface topography, even if combined with any other treatments. Overall, surface tretments on ZrO 2 not easier than LDS.