The effect of storage media upon the surface microhardness and abrasion resistance of three composites

doi:10.1016/S0109-5641(05)80042-9

Dental Materials

Volume 6, Issue 2, April 1990, Pages 123-128

https://doi.org/10.1016/S0109-5641(05)80042-9 Get rights and content

Abstract

The effects of various storage media [distilled water, lactate (pH 4.0), and citrate (pH 6.0) buffers] upon the hardness and wear factor values of three composites [Occlusin (O), P-30 (P), and FulFil (F)] were studied.

Over the one-year storage period, the hardness of all three materials stored in citrate buffer was unchanged. In the case of P in water and all materials stored in lactate buffer, a reduction was observed.

There was no significant difference (P > 0.05) between the wear factors of specimens after one year or one week of water storage. Specimens of F stored in citrate buffer had a wear factor (P < 0.01) higher than that of those stored in water. The other materials were not affected by storage in the lactate or citrate buffers.

A reduction in surface hardness for some materials did not result in an increase in wear rate. This indicates that the softening effect was limited to a thin surface layer. Although not significant in vitro, this effect would probably increase the rate of in vivo wear, since the softened material would be lost, exposing a fresh surface to further attack. This would adversely prejudice the material's long-term clinical durability by impairing its resistance to abrasion.

References (16)

DraughnR.A. et al.
Relationship between Abrasive Wear and Microstructure of Composite Resins
J Prosthet Dent
(1978)
HarrisonA. et al.
Abrasive Wear, Tensile Strength and Hardness of Dental Composite Resins—Is there a Relationship?
J Prosthet Dent
(1976)
RouletJ.F. et al.
Influence of Oral Fluid on Composite Resin and Glass Ionomer Cement
J Prosthet Dent
(1984)
WattsD.C. et al.
Surface Hardness Development in Light-cured Composites
Dent Mater
(1987)
Revised American Dental Association Specification No. 1 for Dental Amalgam
J Am Dent Assoc
(1977)
AsmussenE.
Softening of BISGMA-based Polymers by Ethanol and by Organic Acids of Plaque
Scand J Dent Res
(1984)
BradenM. et al.
Diffusion of Water in Composite Filling Materials
J Dent Res
(1976)
HansenE.K.
After Polymerisation of Visible Light Activated Resins: Surface Hardness vs. Light Source
Scand J Dent Res
(1983)

There are more references available in the full text version of this article.

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Dental Materials

Abstract

References (16)

Relationship between Abrasive Wear and Microstructure of Composite Resins

J Prosthet Dent

Abrasive Wear, Tensile Strength and Hardness of Dental Composite Resins—Is there a Relationship?

J Prosthet Dent

Influence of Oral Fluid on Composite Resin and Glass Ionomer Cement

J Prosthet Dent

Surface Hardness Development in Light-cured Composites

Dent Mater

Revised American Dental Association Specification No. 1 for Dental Amalgam

J Am Dent Assoc

Softening of BISGMA-based Polymers by Ethanol and by Organic Acids of Plaque

Scand J Dent Res

Diffusion of Water in Composite Filling Materials

J Dent Res

After Polymerisation of Visible Light Activated Resins: Surface Hardness vs. Light Source

Scand J Dent Res

Cited by (99)

Surface degradation effects of carbonated soft drink on a resin based dental compound

Erosion of CAD/CAM restorative materials and human enamel: An in situ/in vivo study

In vitro evaluation of enamel surface roughness and morphology after orthodontic debonding: Traditional cleanup systems versus polymer bur

Influence of simulated gastric juice on surface characteristics of CAD-CAM monolithic materials

Effect of a demineralization model on the microhardness, surface roughness and topography of giomers: An in vitro study

Investigation of aging resistance for dental resin composites with and without glass flakes