| Popis: |
Aesthetic appearance and function of ceramic inlays, considering color stability, material strength and durability, depends on roughness of ceramic inlay surface. Ceramic blocs Cerec VITA MARK II (Vita Zahnfabrik, Germany) were used to fabricate twenty inlays with Cerec 2 CAD/CIM method (Siemens AG, Germany). Inlays were cemented on prepared extracted teeth. The sample was divided in four groups of 6 specimens and polished with four different techniques: 1. Sof-lex discs grit 150, 360, 600, 1200 (3M, USA) ; 2. Hawe brushes (Hawe Neos Dental, Switzerland) ; 3. Hawe brushes and diamond paste Diabrill (Oralia Dental GmbH, Germany) and 4. Rubber cups (Ivoclar- Vivadent, Liechtenstein). Roughness examination was performed with stylus instrument Perthometer S8P 4.5 (Feinprüf Perthen GmbH, Germany). ANOVA/MANOVA statistical analysis was applied to calculate values of Rz, Ra, Rpm, Rpm/Rz ratio and Material ratio (bearing ratio) from Abbott- Firestone curve. Results revealed significant statistical difference in Ra values for Sof-lex discs (Ra=0, 66 m). Values for Rpm/Rz ratio showed significant difference between use Hawe brushes with diamond paste and use of Hawe brushes (Rpm/Rz=0, 416 m). Material ratio values MR1 were significantly higher for Hawe brushes (MR1=12, 1%). Material ratio values MR2 and values for Rz and Rpm were not significantly different. The obtained results confirm clinical suitability of all polishing methods. Characterization of surface can be made with aid of Rpm/Rz ratio and Material ratio values. It could be concluded that smallest surface roughness was achieved with Sof-lex discs polishing system. All other tested methods are also clinically acceptable. Selection of polishing technique should be made according to the shape of polishing instrument and its possibility to reach all restoration regions. |
