Journal of Research in Dental and Maxillofacial Sciences

en Effect of Polishing and Glazing on Microhardness of Monolithic Zirconia, Lithium Disilicate, and Zirconia-Reinforced Lithium Silicate CAD/CAM Ceramics: An In Vitro Study Restorative Dentistry Restorative Dentistry Original article Original article <div style="text-align: justify;">Background and Aim: This study aimed to assess the effect of polishing and glazing on microhardness of monolithic zirconia, lithium disilicate (LDS), and zirconia-reinforced lithium silicate (ZLS) computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics.    Materials and Methods: In this in vitro study, square-shaped specimens (10 x 10 x 1 mm) were fabricated from Suprinity, IPS e.max CAD, and Incoris ZI ceramics (n=24 from each). Each group was subdivided into three subgroups (n=8) for (I) glazing, (II) polishing with Diapol Twist kit, and (III) no surface treatment (control). Microhardness was assessed using Vickers hardness tester. Comparisons were made with two-way ANOVA and Tukey’s test (alpha=0.05).    Results: Ceramic type had a significant effect on microhardness (P<0.001) such that Incoris ZI showed the highest, and IPS e.max CAD showed the lowest microhardness (P<0.05). The effect of surface treatment on microhardness was also significant (P<0.001) such that the control group showed the highest and the polishing group showed the lowest microhardness (P<0.05). The interaction effect of ceramic type and surface treatment on microhardness was not significant (P=0.454). Conclusion: Within the study limitations, the findings showed that the microhardness values differed significantly across groups, and the control group had a higher microhardness than the polishing and glazing groups. The values tended to be higher for Incoris ZI ceramic, indicating that this ceramic may demonstrate greater wear resistance in clinical situations.  </div> Computer-Aided Design, Dental Polishing, Hardness, Yttria stabilized tetragonal zirconia 251 258 http://jrdms.dentaliau.ac.ir/browse.php?a_code=A-10-369-1&slc_lang=en&sid=1 Sayyed Mohammad-Reza Ghelmani 100319475328460017643 100319475328460017643 No Department of Prosthodontics, TeMS.C., Islamic Azad University, Tehran, Iran. Reza Nahidi rezanahidi@gmail.com 100319475328460017644 100319475328460017644 Yes Department of Prosthodontics, TeMS.C., Islamic Azad University, Tehran, Iran. Arash Zarbakhsh Arashz1350@gmail.com 100319475328460017645 100319475328460017645 No Department of Prosthodontics, TeMS.C., Islamic Azad University, Tehran, Iran.