INFLUENCE OF A BASE ON CORONAL MICROLEAKAGE OF POST-PREPARED TEETH

This study compared the coronal microleakage of post-prepared teeth wi th and without the placement of a zinc oxide-eugenol cement seal coron al to the gutta-percha. Forty single-rooted extracted teeth were prepa red and obturated with sealer and gutta-percha. These teeth were divid ed into two groups of teeth 20 each. A post space was prepared for eac h tooth so that 5 to 6 mm of gutta-percha remained in one group and 3 to 4 mm in the other group. To the latter group, 2 to 3 mm of zinc oxi de-eugenol cement base was placed directly coronal to the gutta-percha . The sealer was allowed to set for 48 h and the outer root surfaces o f the teeth were covered with finger nail varnish and sticky wax, exce pt for the access openings. The teeth were immersed in dye for 1 wk to allow coronal microleakage. The specimens were sectioned and measurem ents were made on the extent of dye penetration into the root filling. The teeth without a zinc oxide-eugenol base showed significantly grea ter microleakage than those protected with a zinc oxide-eugenol base.