BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    AARHUS SCREW

    MDR report key: 8055191 · Received November 9, 2018

    Report

    Report Number
    8010099-2018-00001
    Event Type
    Malfunction
    Date Received
    November 9, 2018
    Date of Event
    April 1, 2017
    Report Date
    November 9, 2018
    Manufacturer
    MEDICON E.G.
    Product Code
    DZE
    UDI-DI
    04046826385484
    PMA / PMN Number
    K041527
    Adverse Event
    Yes
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    IT
    Reporter Occupation
    OTHER

    Narratives

    Additional Manufacturer Narrative · 1

    THE SCREW WAS SUBJECT TO VISUAL AND MICROSCOPIC INSPECTION. IT HAD BROKEN AT THE SECOND THREAD CLOSE TO THE SCREW HEAD. THE SCREW HEAD PROFILE SHOWED CLEAR SIGNS OF STRESS, INDICATING THAT A HIGH TORQUE WAS APPLIED WITH THE SCREWDRIVER. THE FRACTURE SITE ITSELF SHOWED AN ALVEOLAR, CIRCULAR FRACTURE PATTERN. THE FRACTURE WAS A TORSIONAL FRACTURE CAUSED BY SCREW OVERLOADING. THE SCREW BROKE WHILE IT WAS BEING INSERTED INTO THE BONE. DURING INSERTION OF A SCREW INTO BONE, THE TORSIONAL FORCE INCREASES WITH EVERY TURN. THE SCREW FRACTURED AT THE SPOT WHERE THE TORSIONAL FORCE IS TRANSLATED FROM THE TIP OF THE THREAD TO THE SHAFT. WHEN A SCREW IS OVERWOUND IT ALWAYS FRACTURES AT THIS POINT. OVERWINDING OCCURS WHEN THE TORSION FORCE PRODUCED BY THE SCREWDRIVER IS INCREASED ALTHOUGH THE SCREW CANNOT BE INSERTED ANY FURTHER. THE SCREW HAS REACHED ITS POINT OF MAXIMAL FIXATION IN THE BONE, THE USER DOES NOT RECOGNIZE THIS AND CONTINUES TURNING THE SCREW ALTHOUGH THE BONE IS TOO HARD FOR INSERTION OF THE FULL SCREW LENGTH WITHOUT PREDRILLING. MANUFACTURING RECORDS WERE REVIEWED AND SHOWED NO DEVIATIONS FROM SPECIFICATIONS. THE FRACTURE WAS DUE TO USER ERROR.

    Description of Event or Problem · 1

    THE ORTHODONTIC SCREW BROKE AS IT WAS BEING INSERTED INTO THE PATIENT'S JAW. THE BROKEN PIECE WAS REMOVED IMMEDIATELY. NO HARM TO PATIENT.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    895715 AARHUS SCREW ORTHODONTIC SCREW DZE MEDICON E.G. 094283//200115 04046826385484

    Patients

    Seq Age Sex Outcome Treatment
    1 Required Intervention