In Vitro Microscopic Evaluation of Metal- And Zirconium-Oxide-Based Crowns’ Marginal Fit

Abstract

Objective: To evaluate the marginal adaptation of computer-aided designing and computer-aided machining (CAD/CAM) fabricated cobalt-chromium and zirconium-oxide-based ceramic crowns compared to those produced by a conventional method. Material and Methods: The study consists of three groups; 45 crowns fabricated from cobalt-chromium (CAD-CoCr) and 45 crowns manufactured from zirconium CAD/CAM technology (CAD-Z), and 45 control (C) which consists of conventional metal-ceramic crowns. The marginal discrepancies in vertical dimensions were assessed utilizing a microscope in four surfaces (mesial, distal, vestibular, and oral) for each crown. On completion of the microscopic evaluation, multivariate analysis of variance (MANOVA) was used to study the difference in the four surfaces, considered altogether. Two-way ANOVA revealed the effect of three systems used for gap measurements of each landmark. The differences observed were considered significant at p<0.05. Results: There were no differences in the four surfaces revealed by АNOVА in the three groups when considered altogether. Twoway ANOVA of each surface discovered no differences among all groups as well. Conclusion: The CAD/CAM crowns revealed a comparable and satisfactory marginal adaptation compared to conventional metal-ceramic crowns.

Effect of Erosive Agents on Surface Characteristics of Nano-Fluorapatite Ceramic: An In-Vitro Study

“…Therefore, in order to overcome this limitation, scanning electron microscope (SEM) photomicrographs were utilized in the current study, which provides two-dimensional qualitative views. Hence, a combination of quantitative surface evaluation through Ra values and qualitative assessment by SEM analysis provides a true description of the evaluated specimen surfaces [ 31 ]. Additionally, measurements of surface roughness obtained from SEM scans may not represent or be generalized for the entire specimen surface.…”

Effect of Different Shading Techniques on the Color of Zirconia Ceramic Restoration (An In vivo Study)

“…The crowns were tried inside the patient mouth prior to glazing for detecting accuracy of fitting, contacts, and any occlusal adjustment to avoid removal of the glazing layer by occlusal adjustment [33] that may lead to more abrasive wear of the opposing teeth. The margins of each crown were evaluated using dental explorer and a magnification loupe to assess the marginal fit of the restorations as the increased marginal discrepancy results in a thick layer of cement affected by the oral cavity environment, causing cement dissolution with further tooth biofilm accumulation and marginal discoloration [34].…”

Synthetic materials in craniofacial regenerative medicine: A comprehensive overview

“…Nevertheless, when the pH is lower than 5.6, the produced acidic abused materials stimulate a local inflammatory reaction and dissolve the surrounding apatite, which is the major drawback of these scaffolds. Among the polymeric scaffolds, PLGA, PLCL, and other polyester and their copolymer are widely used (Pangesty et al, 2017;Mirchandani et al, 2021;Shetty et al, 2021;Srimaneepong et al, 2021;Srimaneepong et al, 2022a;Mirza et al, 2022;Mubaraki et al, 2022;Patel et al, 2022;Ramzan et al, 2022;Syed et al, 2022). They can also be produced in different sizes, including nano-scales; however, insufficient ECM-mimicry and possible toxic byproducts after degradation are noticeable limitations of synthetic materials (Marti et al, 2013).…”

“…It is important to note that they have many disadvantages, including the fact that they are highly susceptible to contamination by bacteria (like endotoxins), lack tunability, react immunologically, degrade at an uncontrollable rate, and do not have a mechanical expectations. In terms of biological aspects, these have several disadvantages in terms of their lack of cellular adhesion sites, so they require chemical modification to enhance the cells’ adhesion to them to improve their performance ( Heboyan et al, 2018a ; Heboyan et al, 2018b ; Heboyan et al, 2020a ; Heboyan et al, 2020b ; Heboyan et al, 2021b ; Reddy et al, 2021 ; Heboyan et al, 2022b ; Heboyan et al, 2022c ; Marya et al, 2022c ; Heboyan et al, 2022d ; Heboyan et al, 2022e ; Heboyan et al, 2022f ; Kakkad et al, 2022 ; Karobari et al, 2022 ). The following describes the most synthetic materials used in craniofacial TE.…”