Masking ability of lithium disilicate over different types of post and core systems
Date
2012
DOI
Authors
Nazarian, Mohammad Ali
Version
OA Version
Citation
Abstract
Objectives: The aim of this study is to determine the masking ability of 2 types of ceramics (high translucency and low translucency) by measuring their luminance and color difference over five different backgrounds.
Materials and Methods: Sixteen specimens were made from e.max CAD blocks Number 12 shade A2 (eight LT and eight HT) in thickness of 1.5 mm. Six different substructures were made out of yellow gold, white gold, silver palladium (to simulate the core) and dental die materials (control group). One sample of yellow gold and silver specimen was polished with a carbide bur, the other being silver and yellow gold specimens were sandblasted on one surface. Another sample of white gold was coated by two layers of opaque. The control group was made of dentin die materials (ND3 shade) to simulate the natural dentin color (not a discolored tooth). Each background was covered once by LT and a second time by HT group. Try-in transparent cement was used to join them temporarily. Specimens were evaluated with spectrophotometer machine to evaluate the coIor of each ceramic group (HT and LT) over different backgrounds and the computer extracted the data. Means were calculated and analyzed with one way ANOVA and Tukey's HSD ([alpha]=.05).
Results: There was a significant difference between polished and sandblasted specimens on appearance under LT and HT groups, with gold polished samples providing the best result for HT and LT ceramics. There was not a significant difference between gold and silver sand blasting samples. In the LT group, a statistical difference can be seen between gold polished, silver sand blasted and opaque (0.05), while in LT groups there were no statistical differences between silver polished and opaque.
Conclusions: Both LT and HT can mask effectively mask the gold polished group. Both sand blasted groups displayed inadequate masking abilities.
Description
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Dissertation (MSD) --Boston University Institute for Dental Research and Education, Dubai, 2012 (Prosthodontics).
Includes bibliographic references: leaf 34.
Dissertation (MSD) --Boston University Institute for Dental Research and Education, Dubai, 2012 (Prosthodontics).
Includes bibliographic references: leaf 34.
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This work is protected by copyright. Downloading is restricted to the BU community. If you are the author of this work and would like to make it publicly available, please contact open-help@bu.edu.