Purpose: To evaluate the effects of the different available intraoral ceramic polishing systems on the surface roughness of the latest ceramic materials. Methods: Eighty ceramic discs (5mmx2mm) were prepared from 2 ceramic materials (VM9 and e.max) using stainless steel mold. The discs were then randomly divided into 4 subgroups for each material (n=10). A Fine diamond bur was used to remove the glaze layer on one side of the disc (the other side serving as a control), and the samples were then polished by one of the 4 polishing systems (Sof-lex discs, Optrafine, EVE, and Jazz). Surface roughness was measured quantitatively by Profilometer and qualitatively by SEM. Three roughness readings were taken for each sample before being polished, after removal of the glaze layer, and after being polished. Results: The mean Ra value for the glazed surface (control) was (Ra=0.557). The lowest mean Ra value was recorded for the Sof-lex polishing system with the e.max material (Ra=0.195). The highest mean Ra value was recorded for the Jazz polishing system with the VM9 material. There was no statistically significant difference between Optrafine and EVE with VM9 and Sof-lex, Optrafine and EVE with e.max. Conclusion: The use of ceramic polishing kits was effective in reducing surface roughness. The polished ceramic samples were as smooth as their controls. Therefore, any needed adjustment to the ceramic restoration can be achieved by the use of a ceramic polishing kit, without the need for glazing.

Objectives. Esthetics is an essential issue for the long-term success of composite resin restoration. Therefore, this study aimed to view the esthetics of universal shade composite resin restorations and to assess its color matching before and after bleaching. Materials and Methods. Overall, 40 freshly extracted premolars were mounted in an acrylic resin mold, and Class V cavities were then prepared and restored by OMNICHROMA composite (Tokuyama Dental, Tokyo, Japan) and polished with 2-step polishing system. Baseline color analysis was performed using VITA Easyshade V digital spectrophotometer, and another color analysis was carried out 24 hours after storage in distilled water. In-office bleaching was carried out, and color measurements were taken after bleaching and 2 weeks postbleaching. The data were statistically analyzed using SPSS 26.0 Windows version statistical software. Changes were considered statistically significant at P  = 0.05. Results. ΔE value of OMNICHROMA restoration before and after restoration was 6.474, 3.529 before and after bleaching, and 3.651 two-weeks postbleaching. In-office bleaching was effective in bleaching the OMNICHROMA specimens as the restoration showed positive ΔL ∗ values, which indicated that the specimens were lighter in color after bleaching; however, the bleaching effect was not maintained after 2 weeks. Conclusion. OMNICHROMA universal shade composite resin restoration showed different color matching values with the adjacent enamel of class Vs. The material appeared lighter in shade postbleaching, and the color change was not maintained 2 weeks postbleaching.

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The study aimed to analyze the effect of the addition of nano-hydroxyapatite (nano-HA) particles on the mechanical properties of experimental adhesive (EA). Furthermore, dentin interaction of EA (without nano-HA) and EA with nano-HA (hereon referred to as HA-10%) were also investigated and equated. Methods consisting of scanning electron microscopy (SEM)–energy-dispersive X-ray spectroscopy (EDX), micro-Raman spectroscopy, micro-tensile bond strength (µTBS) test, and Fourier transform infrared (FTIR) spectroscopy were employed to study nano-HA particles shape, dentin bond strength, degree of conversion (DC), and adhesive–dentin interaction. Ninety teeth (N = 90) were collected, and pre-bonding, conditioning of dentin was performed utilizing phosphoric acid (H3PO4) etching, photodynamic therapy (PDT), and ER-CR-YSGG (ECY) laser. The teeth were set to form bonded specimens using two adhesives. Nano-HA particles were spherical-shaped, and EDX confirmed the presence of oxygen, calcium, and phosphorus. Micro-Raman spectroscopy revealed distinct phosphate and carbonate peaks for nano-HA. The µTBS test demonstrated highest values for HA-10% group on the H3PO4 conditioned dentin. The greatest DC was observed for the EA group. The addition of nano-HA-10 wt.% particles in dentin adhesive resulted in improved bond strength. The incorporation also demonstrated acceptable DC (although lower than EA group), suitable dentin interaction, and resin tag formation.

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