Abstract
Glass ionomers chemically and mechanically bond to enamel. Repeated bonding may deplete calcium in enamel and reduce the bond strength. Seventy-five non-carious molars were randomly divided into three equal groups and metal brackets were bonded with either Ketac-Cem, Photac-Bond, or Fuji Ortho LC. The samples were stored in 100% humidity at 37° C for 7 days then shear/peel tested with an Instron machine. New brackets were repeatedly cemented with the same cement to the same tooth and shear/peel tested a total of five times. After each shear/peel test the tooth with the mean bond strength from each cement was set aside for SEM analysis.
From week 1-5, the bond strength of each glass ionomer increased. The increase in bond strength was statistically significant between weeks 1 to 2 and 2 to 5 for each cement and each week for Ketac-Cem (p < 0.001). After the fifth week, teeth bonded with Ketac-Cem or Fuji Ortho LC possessing the highest and lowest bond strengths were evaluated by energy dispersive x-ray analysis (EDX). EDX revealed no significant difference in calcium at the rebonded area when compared with an unbonded adjacent area. SEM images reveal micro-mechanical glass ionomer adhesions. It is thought that these provide the increased bond strength.
LLU Discipline
Orthodontics
Department
Dentistry
School
Graduate School
First Advisor
Willis L. Schlenker
Second Advisor
Daniel A. Flores
Third Advisor
V. Leroy Leggitt
Fourth Advisor
Carlos Muñoz
Degree Name
Master of Science (MS)
Degree Level
M.S.
Year Degree Awarded
1996
Date (Title Page)
8-1996
Language
English
Library of Congress/MESH Subject Headings
Dental Bonding; Dental Enamel; Glass Ionomer Cements; Dental Materials
Type
Thesis
Page Count
2 vii; 40
Digital Format
Digital Publisher
Loma Linda University Libraries
Copyright
Author
Usage Rights
This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.
Recommended Citation
Wilkinson, David L., "Change in Bracket Bond Strength and Enamel Calcium : Due to Repeated Bonding with Conventional and Resinomer Glass Ionomer Cements" (1996). Loma Linda University Electronic Theses, Dissertations & Projects. 1975.
https://scholarsrepository.llu.edu/etd/1975
Collection
Loma Linda University Electronic Theses and Dissertations
Collection Website
http://scholarsrepository.llu.edu/etd/
Repository
Loma Linda University. Del E. Webb Memorial Library. University Archives