Journal of Dental Research, Vol 70, 55-58, Copyright © 1991 by International & American Associations for Dental Research Online Journals
Microleakage of three cement bases
R. J. Heys and M. Fitzgerald
University of Michigan, School of Dentistry, Department of Restorative Dentistry, Ann Arbor 48109-1078.
The purpose of this study was to evaluate the ability of a glass-ionomer
cement-base material to prevent bacterial penetration along the dentin
interface and to compare it with two conventional cement-base materials. A
total of 107 Class 5 restorations was placed in Rhesus monkey teeth by
means of three test materials [zinc oxide-eugenol (ZOE), copalite varnish +
zinc phosphate cement base (V + ZP), and a glass-ionomer lining cement
(GI)], with unetched and unbonded resin composite used alone as a control
material and as a final restoration over the test base materials. Following
disinfection, Class 5 cavities were prepared on the buccal surfaces of the
teeth to the inner one-half of dentin. A sterile filter-paper disk was then
placed on the axial wall and covered with a Teflon disk. Next, the cavities
were based to the dento-enamel junction with one of the test base materials
and finally restored with unetched and unbonded resin composite. After five
and 16 weeks, the filter-paper disks were retrieved and cultivated for the
presence and type of bacteria. The five-week results showed positive growth
in two groups: the composite-only controls and the V + ZP group. The
16-week results showed growth in all of the test groups, but only one of
nine teeth showed growth in the zinc oxide-eugenol group and one of 16
teeth in the glass-ionomer group. The results of this study indicate that
under the conditions tested, a glass-ionomer base was capable of minimizing
bacterial penetration along the material-tooth interface.
