Document Detail

Color change during the surface preparation stages of metal ceramic alloys.
MedLine Citation:
PMID:  21723992     Owner:  NLM     Status:  In-Data-Review    
STATEMENT OF PROBLEM: Even though metal ceramic restorations (MCRs) are widely used by clinicians, the influence of the metal on the color of overlaying porcelain is unknown.
PURPOSE: The purpose of this study was to analyze the color alterations of different types of metal ceramic alloys during several stages of metal surface preparation and to determine the effect of those changes on the resulting color of opaque porcelain (OP).
MATERIAL AND METHODS: Seven different types of alloys (3 base metal, 3 noble, and 1 high noble) were used to prepare disk-shaped specimens (1 mm × 10 mm, n=3), followed by OP application (0.1 mm). L*a*b* values of specimens were recorded after different stages of metal surface preparation (ingot, after casting, after oxidation, and after the OP application) in addition to the shade tab of OP B1 (target shade). L*a*b* values of alloys were measured from the ingot structure to the OP application stage and statistically analyzed (Repeated measures ANOVA, and Bonferroni corrected paired t test, α=.05). L*a*b* values of OP applied groups and the OP shade tab (target shade) were analyzed (1-way ANOVA with Dunnett's multiple comparison test, α=.05). The color differences of the target shade both before and after OP application were calculated and statistically analyzed (1-way ANOVA, Ryan-Einot-Gabriel-Welsch Multiple Range Test, α=.05).
RESULTS: The L* values of all alloys changed significantly after each stage except for 2 alloys (V-Deltaloy SF (N-VDSF)) and (Gnathos Plus (HN-GP)) after casting and airborne-particle abrasion (P<.05). The a* value of all alloys increased after casting. Changes in the a* coordinate were significant except for one of the base metal alloys (P<.05). The a* coordinate changes of alloys showed variation in direction after oxidation and OP application (P<.05). The b* coordinate changes of alloys showed variation in direction after each stage (P<.05). The L*a*b* values of some OP applied alloys were significantly different from that of the OP shade tab (P<.05). Color difference values (ΔE (OP applied alloy-target shade)) of 2 OP-applied alloys (Cerapall 2 (N-CP2) and Ceradelta (N-CD)) were significantly different (P<.05) and higher than the other OP-applied alloys.
CONCLUSIONS: The achromatic color behavior of different alloys was all in the same direction at all metal surface preparation stages. The chromatic behavior of the different alloys was primarily towards the same direction after casting and airborne-particle abrasion, whereas it varied after oxidation and OP application. The color difference of OP for all alloys, regardless of their type, was not visually perceivable when compared to the target shade (ΔE<2.6). (J Prosthet Dent 2011;106:38-47).
Tuncer Burak Ozçelik; Burak Yilmaz; Isil Ozcan; Alvin G Wee
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The Journal of prosthetic dentistry     Volume:  106     ISSN:  1097-6841     ISO Abbreviation:  J Prosthet Dent     Publication Date:  2011 Jul 
Date Detail:
Created Date:  2011-07-04     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0376364     Medline TA:  J Prosthet Dent     Country:  United States    
Other Details:
Languages:  eng     Pagination:  38-47     Citation Subset:  D; IM    
Copyright Information:
Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.
Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Başkent University, Faculty of Dentistry, Ankara, Turkey.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Shear bond strengths of pressed and layered veneering ceramics to high-noble alloy and zirconia core...
Next Document:  Survey of partial removable dental prosthesis (partial RDP) types in a distinct patient population.