|
KMID : 0362320060310040290
|
|
Journal of Korean Academy of Operative Dentistry
2006 Volume.31 No. 4 p.290 ~ p.299
|
|
|
THE EFFECT OF ETHYLENE GLYCOL ANALOGS ON MECHANICAL PROPERTIES OF MOIST DEMINERALIZED DENTIN MATRIX
|
|
Lee Kyung-Ha
Cho Young-Gon
Lee Kwang-Won
|
|
|
Abstract
|
|
|
Objectives: The purpose of this study is to evaluate the effect of ethylene glycol analogs on modulus of elasticity and ultimate tensile strength of moist, demineralized dentin matrix.
Methods: Dentin disks 0.5 mrn thick were prepared from mid-coronal dentin of extracted. unerupted, human third molars. ’’I’’ beam and hour-glass shaped specimens were prepared from the disks, the ends protected with nail varnish and the central regions completely demineralized in 0.5M EDTA for 5 days. Ultimate tensile stress (UTS) and low strain modulus of elasticity (E) were determined with specimens immersed for 60 min in distilled water (H2O), ethylene glycol (HO-CH2-CH2-OH), 2-methoxyethanol (H3CO-CH2-CH2-OH), and 1,2-dimethoxyethane (H3CO-CH2-CH3-OCH3) prior to testing in those same media. Modulus of elasticity was measured on the same specimens in a repeated measures experimental design. The results were analyzed with a one-way ANOVA on ranks, followed by Dunn’’s test at alpha=;0.05. Regression analysis examined the relationship between UTS or E and hoy’’s solubility parameter for hydrogen bonding (delta h) of each solvent.
Results: The UTS of demineralized dentin in water, ethylene glycol, 2-methoxyethanol, and 1,2-dimethoxyethane was 24 (3), 30 (5), 37 (6), and 45 (6) MPa, X (SD) N = 10. Low strain E for the same media were 16 (13), 23 (14), 52 (24), and 62 (22) MPa. Regression analysis of UTS vs delta h revealed a significant (p < 0.0001,r = -0.99,R2 = 0.98) inverse, exponential relationship. A similar inverse relationship was obtained between low strain E vs delta h(p < 0.0005, r = -0.93, R2 = 0.86).
Significance: The tensile properties of demineralized dentin are dependent upon the hydrogen bonding ability of polar solvents (delta h). Solvents with low delta h values may permit new interpeptide H-bonding in collagen that increases its tensile properties. Solvents with high delta h values prevent the development of these new interpeptide H-bonds.
|
|
|
KEYWORD
|
|
|
Polar Solvents, Ethylene Glycol Analogs, Hydrogen Bonding Ability
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
|
|