Retentive Forces of the Prefabricated Post and Composite Resin Cores in Comparison with the Cast Post and Cores
1998 Volume 42 Issue 6 Pages 1054-1065
Details
1998 Volume 42 Issue 6 Pages 1054-1065
Recently, adhesive dentistry has made a lot of progress, and now its effects should be shared by post and core techniques for restoration of endodontically treated teeth. The purpose of this study was to compare the prefabricated metal postand composite resin cores with the conventional cast post and cores with respectto retention. Three kinds of luting cement for the cast post and cores, that is, zinc phosphate cement (EC), Panavia 21 (P 21), and Super-bond C&B (SB) were examined. In addition, three kinds of core build-up technique for the prefabricated post and composite resin cores were prepared for dislodgment tests. They were the prefabricated post cemented with P 21 and light polymerized Clearfil photo core (P 21+PC), the same post and dual polymerized Clearfil DC core (P 21+DC), and the prefabricated post cemented with DC and DC core (DC + DC).
The results were as follows:
1. The dislodgment forces of the cast post and cores cemented with EC were the smallest, although the forces did not decrease after thermocycling.
2. Three kinds of the prefabricated post and composite resin core were equal in retention to the cast metal post and cores cemented with resin cements, P 21 and SB.
3. The cast post and cores cemented with SB, and two types of the prefabricated post and core, P 21+PC and DC+ DC, showed significantly lower values in retention after thermocycling.
4. SEM photographs showed different images in each post and core technique. Fractured dentin surfaces in EC were covered with a smear layer. P 21 and SB were covered using a resin cement layer, and P 21+ PC, P 21 + DC, and DC + DC were covered using a bonding layer.
