Objective: To compare the clinical effects of the restoration of residual crowns and roots with direct and indirect cast dowel-core crowns.
Methods: The direct and indirect techniques were applied to fabricate cast dowel-core in 119 teeth of 91 patients. The direct dowel-cores were made by fabricating wax patterns in the prepared teeth in the patients' mouth; and the indirect dowel-cores were fabricated with wax patterns on casts poured by injecting agar impression material into the canal. Then the completed wax patterns were invested. After finishing the dowel-cores, they were cemented in the teeth. The metalceramic crowns were made to restore these teeth.
Results: Of the 119 teeth, 71 succeeded and 5 failed in 76 dowel-cores made by the direct method; and only 1 tooth failed among the 43 dowel-cores made by the indirect method.
Conclusion: The indirect method using agar impression material can be manipulated easily and conveniently with accurate impressions. The dowel-core fits the root canal and the margin has good adaption. The retention is good and this method is practicable.