Aging and Fracture Resistance of Screw-Retained Implant-Supported Molar Crowns Fabricated from Lithium Disilicate Containing Virgilite.

PURPOSE: To investigate the aging and fracture resistance of screw-retained implant-supported single crowns (iSCs) fabricated from lithium disilicate containing virgilite (VLD).

MATERIALS AND

METHODS

iSCs were fabricated from VLD (CEREC Tessera, Dentsply Sirona) and lithium disilicate (control, n = 8; IPS e.max CAD, Ivoclar) and bonded to a Ti-base abutment. VLD crowns were luted either with (VLDc, n = 8) or without (VLDw, n = 8) a coupling agent. iSCs were cleaned, sterilized, and screw-retained on implants. Fracture force was determined after thermal cycling and mechanical loading (TCML).

RESULTS

All crowns survived TCML. No significant differences in mean fracture forces were identified between VLDc (1,583 N), VLDw (1,694 N), and control (1,797 N; P = .639 ANOVA, P = 1.000 Bonferroni).

CONCLUSIONS

Screw-retained iSCs fabricated from VLD provide acceptable stability, which is independent on the usage of a coupling agent for bonding to Ti-base abutments and sterilization.