Document Detail


Esthetic brackets: the influence of filler level on color stability.
MedLine Citation:
PMID:  17628243     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
INTRODUCTION: An undesirable effect of plastic brackets is their discoloration after a short time in the oral cavity. The objective of this study was to investigate the influence of the filler level of plastic brackets on color stability after exposure to food dyes or ultraviolet (UV) light. METHODS: Three bracket groups were produced with silicon dioxide as the filler: an unfilled urethane-dimethacrylate (UDMA) bracket, a UDMA bracket with filler content of 35% by volume, and a UDMA bracket with filler level of 70% by volume. All brackets were exposed for 72 hours to UV light in an aging device with a xenon lamp to simulate natural daylight or to food dyes (cola or tea). Color measurements were made with a spectrophotometer according to the CIE L*a*b* system, and color changes (DeltaE*) were computed. RESULTS: Greater exogenous discoloration was observed by raising the filler level of UDMA brackets. Almost all investigated polymer brackets showed clinically acceptable color stability during in-vitro exposure to colorants. However, almost all brackets seemed more yellow after UV light treatment. CONCLUSIONS: Silicon-dioxide filler-reinforced UDMA brackets showed an obvious trend for increased exogenous discoloration when filler level was raised. Highly filled brackets were less susceptible to endogenous discoloration caused by UV light.
Authors:
Andreas Faltermeier; Michael Behr; Dieter Müssig
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Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics     Volume:  132     ISSN:  1097-6752     ISO Abbreviation:  Am J Orthod Dentofacial Orthop     Publication Date:  2007 Jul 
Date Detail:
Created Date:  2007-07-13     Completed Date:  2007-07-24     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8610224     Medline TA:  Am J Orthod Dentofacial Orthop     Country:  United States    
Other Details:
Languages:  eng     Pagination:  5.e13-6     Citation Subset:  D; IM    
Affiliation:
Department of Orthodontics, University Medical Center of Regensburg, Regensburg, Germany. Andreas.Faltermeier@klinik.uni-regensburg.de
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MeSH Terms
Descriptor/Qualifier:
Color
Colorimetry
Esthetics, Dental*
Food Coloring Agents
Materials Testing
Methacrylates* / chemistry,  radiation effects
Orthodontic Brackets*
Polyurethanes* / chemistry,  radiation effects
Silicon Dioxide / radiation effects
Ultraviolet Rays
Chemical
Reg. No./Substance:
0/Food Coloring Agents; 0/Methacrylates; 0/Polyurethanes; 0/polyurethane dimethacrylate; 7631-86-9/Silicon Dioxide

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


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