About three years after the restoration was completed, the patient comes into the office with the two crowns in his hand. In the top picture you can see the crowns and a broken retentive screw. The right crown has a portion of the implant stillattached to it. The x-ray shows the broken implant.

What happened here is that one retentive screw fractured in the implant and the other did not. Instead, the preassure on the implant caused it to fracture and the entire restoration to come loose.

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