Clinical Evaluation of Chairside CAD/CAM Lithium Disilicate Implant Restorations

Objectives: Chairside CAD/CAM implant restorations with the CEREC system (Dentsply Sirona) became available in January 2014. This retrospective clinical study evaluated the clinical performance of chairside CAD/CAM monolithic lithium disilicate (LD) restorations for single implants.
Methods: Patients who had at least one implant restored with a chairside CAD/CAM workflow were recalled between 6-months and 3-years following placement of the final restoration. Four clinicians experienced with chairside CAD/CAM restorations delivered all restorations. The restorations were fabricated from an intraoral digital scan (OmniCam/Dentsply Sirona), designed and milled (MCX Mill/Dentsply Sirona) from lithium disilicate blocks (emaxCAD/Ivoclar), crystallized, and adhesively bonded to a TiBase (Dentsply Sirona) according to the implant specifications per manufacturers instructions.
Results: A total of 55 restorations were evaluated; 50 were screw-retained and 5 were cement-retained LD crowns with custom chairside CAD/CAM LD abutments. There were 26 cases recalled up to one year, 20 cases up to 2 years, and 9 cases up to 3 years from restoration placement. There were no documented mechanical problems with any restoration including screw failures or restoration chipping or fracture. 50 of the cases had an average of 2.5 mm keratinized gingiva and 5 cases had no keratinized gingiva, all without gingival recession exposing the implant. Lateral guidance was present on 14 of the implant restorations and 40 of the patients had clinical evidence of bruxism with no signs of mobility to the restoration. 24 cases had less than 50% of the embrasure space filled by the gingival papilla, 19 cases had greater than 50% of the embrasure filled, and an additional 11 cases had the entire embrasure space filled by the gingival papilla.
Conclusions: Chairside CAD/CAM monolithic lithium disilicate implant restorations have performed well clinically for a period of up to 3 years. This study was supported by a grant from Ivoclar.