Dental Ceramics: Atomic force microscope - AFM and surface roughness

Objective: This study analyzed the conditioner influence with the HF 10% and the polishing with rubber on ceramics surfaces VMK 95 (feldspatic), Omega 900 (with alumina), IPS.d.SIGN e Cergogold (ceramics glasses). The parameters Ra e Ry of roughness (Surftest 301) were used. The AFM observations (Nanoscope III-a) were made polished in surfaces. Methods: Fifteen cones of each kind of ceramic being the largest base area were used. The cones were imbedded in acrylic resin and mechanic polished (Struers) using a sandpaper sequence. Six surfaces of cones were conditioned for 2 minutes with HF 10%. Nine surfaces of cones were polished with rubber sequence RK1, LK2 and RK4 (Reddish Stone) where 6 cones were assigned to roughness test and 3 to AFM. The AFM cones were cleaned with acetone; detergent plus distilled water and ethylic alcohol after polishing. In the roughness test the ceramic cones were divided in 16 groups. Results: The ANOVA and Tukey statistical tests were applied. The average of the results follow letters (the same letters show similar results – p < 0,05). To Ra/Pol: G1-VMK 0,8±0,3b, G2-Omega 0,6±0,1ab, G3-IPS 0,6±0,1ab e G4-Cergogold 0,5±0,1a. To Ra/HF: G5-VMK 4,5±1,4d, G6-Omega 2,7±0,5c, G7-IPS 2,4±0,6c e G8-Cergogold 2,3±0,7c. To Ry/Pol: G9-VMK 5,0±1,2f, G10-Omega 4,6±0,8ef, G11-IPS 4,6±1,0ef e G12-Cergogold 3,5±0,3e. To Ry/HF: G13-VMK 31,7±10,6h, G14-Omega 17,1±3,9g, G15-IPS 15,5±2,6g e G16-Cergogold 17,5±6,1g. The images captured on the AFM test were analyzed through surface smoothness. Conclusion: The ceramic VMK 95 and the ceramic glass Cergogold showed respectively the highest roughness values after conditioning and the highest smoothness values after polishing.