Implant-Supported Cantilever Fixed Dental Prosthesis in the Anterior Region: Effect of Implant Type and Aging In Vitro.

OBJECTIVES

To investigate if the fracture load of implant-supported cantilever fixed dental prostheses (ICFDPs) in the anterior region is affected by the implant type and the aging protocol.

MATERIALS AND

METHODS

Sixty ICFDPs were prepared using multilayer monolithic zirconia for restoring bone-level (BL) and tissue-level (TL) titanium-zirconium implants. Fracture load was measured at baseline (no aging) or after aging in a chewing simulator loading the implant crown or the cantilever in a 30° angle (n = 10 per group). A two-way ANOVA was applied (α = 0.05) for the effects of implant type and aging protocol.

RESULTS

Implant type (p < 0.001) and aging (p < 0.001) had a significant effect on fracture load values. Baseline specimens of both BL (665 ± 62 N) and TL (554 ± 23 N) had significantly higher mean fracture load values than those of aged specimens(BL implant crown 545 ± 46 N, BL cantilever 563 ± 45 N, TL implant crown 455 ± 32 N, TL cantilever 476 ± 24 N) (p < 0.001). The loading position during aging did not affect fracture load values for BL (p = 0.980) nor TL (p = 0.749). BL implants failed by cement fracture and abutment deformation, while for TL the transmucosal part of the implant deformed.

CONCLUSIONS

The fracture load values of anterior ICFDPs decrease with aging in a chewing simulator. BL implants are preferable over TL implants for anterior ICFDPs as higher fracture load values were achieved, and no implant deformation occurred.