Coronal microleakage of permanent lingual access restorations in endodontically treated anterior teeth

Forty-six intact extracted human anterior teeth were treated endodontically with laterally condensed gutta-percha and sealer. The teeth were restored with a base of either zinc phosphate or temporary stopping and a permanent restoration of either acid etched composite resin with GLUMA as the dentin bonding agent or with Ketac-Fil glass ionomer. The teeth were thermocycled, coated with nail varnish (except for the access), immersed in silver nitrate, developed, and sectioned longitudinally. The linear dye penetration was measured. All restorations permitted leakage into the base. All groups had specimens which leaked into the gutta-percha. There was a tendency for the glass ionomer/zinc phosphate group to leak least, but there were no statistically significant differences among the groups.