Year : 2020 | Volume
: 10 | Issue : 5 | Page : 652--658
Marginal fit of full contour monolithic zirconia in different thicknesses and layered zirconia crowns
Mina Mohaghegh1, Maryam Firouzmandi2, Elham Ansarifard1, Laleh Ramazani4
1 Department of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
2 Department of Restorative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
Aim: Use of monolithic zirconia for fabrication of all-ceramic crowns eliminates several shortcomings of layered zirconia crowns. Long-term success of restorations highly depends on the marginal fit. The crown thickness is among the factors that affect the marginal integrity. Meanwhile, reduced thickness of crowns has several advantages such as preservation of tooth structure. The aim of this study was to evaluate the marginal fit of monolithic zirconia crowns in reduced thickness and to compare the marginal fit of full-contour monolithic zirconia in different thicknesses with layered zirconia crowns. Materials and Methods: In this in vitro study, two standard brass dies (7 mm × 5 mm length diameter) were prepared with a heavy chamfer finish line with 0.5 and 1 mm depth. By using a CAD-CAM system, 30 crowns were made in three groups (n = 10) of 1-mm thick layered zirconia, 1-mm thick monolithic zirconia, and 0.5-mm thick monolithic zirconia. Crowns were placed on master dies and randomly numbered. The marginal gap was measured on 18 points by using a digital microscope (×230). The mean ± standard deviation (SD) values were calculated and analyzed by Statistical Package for the Social Sciences (SPSS) software program through Kruskal–Wallis and Mann–Whitney tests (α = 0.05). Results: The marginal gap of 1-mm layered zirconia was significantly different from that of 1-mm monolithic zirconia (P = 0.001) and 0.5-mm monolithic zirconia (P = 0.004). Analysis of variance (ANOVA) revealed no significant difference between 0.5 and 1 mm thicknesses of monolithic zirconia (P = 0.141). Conclusion: Marginal gap in all the three groups was clinically acceptable. The two different thicknesses of monolithic zirconia crowns had no significant effect on the restoration marginal fit; however, layered zirconia crowns showed a significantly higher marginal gap than monolithic zirconia crowns.
Prof. Elham Ansarifard
Department of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz.
|How to cite this article:|
Mohaghegh M, Firouzmandi M, Ansarifard E, Ramazani L. Marginal fit of full contour monolithic zirconia in different thicknesses and layered zirconia crowns.J Int Soc Prevent Communit Dent 2020;10:652-658
|How to cite this URL:|
Mohaghegh M, Firouzmandi M, Ansarifard E, Ramazani L. Marginal fit of full contour monolithic zirconia in different thicknesses and layered zirconia crowns. J Int Soc Prevent Communit Dent [serial online] 2020 [cited 2020 Nov 23 ];10:652-658
Available from: https://www.jispcd.org/article.asp?issn=2231-0762;year=2020;volume=10;issue=5;spage=652;epage=658;aulast=Mohaghegh;type=0