Surface roughness of five different dental ceramic core materials after grinding and polishing

Abstract

In clinical practice, core materials can be exposed after adjustments are made to previously-luted all-ceramic restorations. The purpose of this study was to evaluate the surface roughness of five different dental ceramic core materials after grinding and polishing. Five different ceramic core materials, Vita In-Ceram Alumina, Vita In-Ceram Zirconia, IPS Empress 2, Procera AllCeram, and Denzir were evaluated. Vita Mark II was used as a reference material. The surface roughness, Ra value (mum), was registered using a profilometer. The measurements were made before and after grinding with diamond rotary cutting instruments and after polishing with the Sof-Lex system. The surface of representative specimens was evaluated qualitatively using scanning electron microscopy (SEM). Results were statistically analysed using analysis of variance (anova) supplemented with Scheffè's and Bonferroni multiple-comparison tests. Before grinding, Procera AllCeram and Denzir had the smoothest surfaces, while IPS Empress 2 had the coarsest. After grinding, all materials except IPS Empress 2 became coarser. Polishing with Sof-Lex provided no significant (P > 0.05) differences between Denzir, Vita Mark II and IPS Empress 2 or between Procera AllCeram and In-Ceram Zirconia. There were no significant differences (P > 0.05) either between the ground and the polished Procera AllCeram or In-Ceram Alumina specimens. Polishing of Denzir, IPS Empress 2 and In-Ceram Zirconia made the surfaces smoother compared with the state after grinding, whereas the polishing effect on Procera AllCeram and In-Ceram Alumina was ineffective. The findings of the SEM evaluation were consistent with the profilometer readings.

Evaluation of Surface Roughness of Monolithic Zirconia after Using Different Polishing Kits

“…Clinically, the kits tested in this study enhanced acceptable polished surfaces, even with statistically significant difference between GP1 and GP2. Furthermore, the values were lower than those found by Kou (0.7 μm) using sof-lex disks (3M, USA) [18] and Lawson (1.1 μm) using the Dialite ZR kit (Brasseler, USA) [7].…”

Porcelain Refinishing with Two Different Polishing Systems after Orthodontic Debonding

“…Although the main indication for polishing discs, which are commonly used in dental clinics, is finishing and polishing dental composite resins, the best polishing results for several types of porcelain were also achieved using the SofLex system in earlier studies. [37][38][39] Furthermore, it was reported that only flat and convex surfaces can be ef- fectively polished with flexible polishing discs such as the Sof-Lex system. 39 Therefore, based on the findings of the present study, polishing discs seem to be effective for polishing porcelain surfaces after orthodontic appliances have been removed.…”

“…[37][38][39] Furthermore, it was reported that only flat and convex surfaces can be ef- fectively polished with flexible polishing discs such as the Sof-Lex system. 39 Therefore, based on the findings of the present study, polishing discs seem to be effective for polishing porcelain surfaces after orthodontic appliances have been removed.…”

Performance of Different Polishing Techniques for Direct CAD/CAM Ceramic Restorations

“…[8][9][10] Sof-Lex discs have also been described as an efficient polishing method for dental ceramics: [11][12] Depending on the ceramic material used and the profilometrical measuring parameters, Ra values ranging from 0.2 µm to 0.7 µm have been achieved. [13][14][15] Furthermore, there are studies indicating that polished surfaces are qualitatively inferior to glazed ones, while other authors describe polished and glazed surfaces as being equivalent in surface roughness. 10,13,[16][17][18][19][20] In summary, results concerning polishing systems and their performance are inconsistent, because of different measuring parameters and different combinations of polishing method and ceramic material.…”