Journal of Dental Research, Vol 63, 1315-1320, Copyright © 1984 by International & American Associations for Dental Research Online Journals
Intermediate restoratives from n-hexyl vanillate-EBA-ZnO-glass composites
G. M. Brauer and J. W. Stansbury
Vanillate esters such as n-hexyl vanillate (HV) dissolved in a suitable
chelating agent - e.g., o-ethoxybenzoic acid (EBA) - react with zinc oxide,
aluminum oxide, and hydrogenated rosin powder to yield
non-eugenol-containing cements that do not inhibit polymerization and are
compatible with acrylic monomers. These cements can be modified by adding
methyl methacrylate, or the less-volatile, higher-molecular-weight
dicyclopentenyloxyethyl, or cyclohexyl methacrylate to the HV-EBA liquid,
and silanized glass to the powder. On incorporating a suitable
initiator-accelerator system, one can prepare powder-liquid mixes that have
good working properties and harden in five to 10 min. The cured materials
containing monomethacrylate ingredients have compressive and tensile
strength one and one-half to three times that of eugenol-based intermediate
restoratives. Cements with even better mechanical properties are obtained
using dimethacrylates as monomeric components. Storage stability of the
liquids comprising vanillates-EBA and monomethacrylates is excellent. The
vanillate-EBA-dimethacrylate liquid containing amine accelerators
polymerizes within days when left standing at 45 degrees C. The cement
composites adhere strongly to composites, non-precious metals, or
porcelains. Rupture of the bond occurs cohesively within the cement.
Because of their high strength, low solubility, and excellent adhesion,
these cements, subject to their biocompatibility with dental tissues, show
great promise as intermediate restorative resins and in the repair of
fractured porcelain or porcelain-to-metal crowns and bridges.
