Purpose: To evaluate the fatigue and fracture resistance of anterior implant-supported and tooth-supported crowns made of different monolithic ceramics. Materials and Methods: Anterior crowns were fabricated of lithium disilicate or one of two zirconia ceramics and were tested as tooth-supported (reference) or as implant-supported crowns with chairside or labside (screw channel) procedures. After thermocycling and mechanical loading (TCML), crowns were loaded to fracture. Results: All crowns survived TCML. Implant-supported crowns (chairside and labside) showed higher fracture values than tooth-supported crowns. Fracture resistance was comparable or higher for zirconia than for lithium disilicate crowns. Conclusion: Implant-supported ceramic crowns may withstand clinical anterior loading forces.