Short fiber reinforced composite in restoring severely damaged incisors

To evaluate the static-load-bearing capacity of severely damaged endodontically-treated incisors restored with short fiber composite (SFC) as a direct post-core-crown complex and to investigate the effect of SFC on the failure mode of the restorations.

The clinical crowns of 40 maxillary incisors were prepared by cutting 2/3 parts of the crown horizontally. Five groups were fabricated (n = 8) using the direct technique; Group A: Crown restorations from conventional composite (CC); Group B: FRC-posts with core-crown restorations from CC; Group C: Crown restorations from SFC; Group D: FRC-posts and core-crown restorations from SFC; Group E: Post-core-crown restorations from SFC. The posts were cemented with dual-cure resin cement. The restorations were polymerized with a hand-light curing unit. All restored teeth were stored in distilled water at 37°C for 5 days before they were statically loaded. Initial fracture (IF) and final fracture (FF) were recorded. Failure modes were visually examined.

ANOVA revealed that SFC restorations had greater IF (469.8 N) and FF load values (515.8 N) (p < 0.05) than the CC restorations (164.8 N). No significant difference for both IF and FF was observed among groups C, D and E. Group E revealed a more favorable fracture mode than any other material combination used.

The use of SFC as a restorative material for fabricating the direct composite post-core-crown restorations of severely damaged incisors provided improved load-bearing capacity than CC used alone or with FRC post reinforcement.