BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    NSK

    MDR report key: 6070303 · Received November 1, 2016

    Report

    Report Number
    9611253-2016-00062
    Event Type
    Malfunction
    Date Received
    November 1, 2016
    Date of Event
    October 1, 2016
    Report Date
    March 10, 2017
    Manufacturer
    NAKANISHI INC.
    Product Code
    EGS
    PMA / PMN Number
    K972569
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    CA, US
    Reporter Occupation
    DENTIST

    Narratives

    Additional Manufacturer Narrative · 0

    EXEMPTION NUMBER E2016004. (B)(4). (B)(4) TOOK THE FOLLOWING ACTIONS FOR MORE INFORMATION ABOUT THE EVENT, HOWEVER, THE DETAILED INFORMATION WAS NOT PROVIDED. ON OCTOBER 6, 2016, RIGHT AFTER BECOMING AWARE OF THE EVENT, (B)(4) CONTACTED THE DENTAL OFFICE AND SPOKE WITH THE OFFICE MANAGER. THE MANAGER EXPLAINED THAT THE PATIENT WAS NOT INJURED AND REQUESTED (B)(4) TO EMAIL THE INFORMATION REQUEST FORM (QA-011) TO THE OFFICE. THE MANAGER PROMISED TO COMPLETE AND SEND BACK THE FORM IMMEDIATELY. (B)(4) SENT THE INFORMATION FORM AS REQUESTED. NO RESPONSE WAS RETURNED FROM THE DENTAL OFFICE. ON OCTOBER 7, 2016, (B)(4) MADE A FOLLOW-UP CALL TO THE OFFICE MANAGER AND INQUIRED IF ANY ASSISTANCE WAS NEEDED. THE OFFICE MANAGER STATED THAT SHE WOULD COMPLETE AND EMAIL THE FORM BACK TO (B)(4). (B)(4) RECEIVED NO RESPONSE. ON OCTOBER 11, 2016, (B)(4) LEFT A VOICE MAIL MESSAGE FOR THE OFFICE MANAGER, BUT (B)(4) DID NOT RECEIVE ANY RESPONSE. DESPITE ALL THE ABOVE EFFORTS, (B)(4) COULD NOT OBTAIN THE FURTHER INFORMATION INCLUDING THE PATIENT INFORMATION.

    Description of Event or Problem · 0

    ON OCTOBER 13, 2016, NAKANISHI RECEIVED AN E-MAIL FROM A DISTRIBUTOR ((B)(4)) ABOUT HANDPIECE PARTS COMING OFF. DETAILS ARE AS FOLLOWS. ON OCTOBER 6, 2016, (B)(4) WAS MADE AWARE OF THE EVENT BY INCOMING SERVICE REPAIR PAPERWORK. THE EVENT OCCURRED ON (B)(6) 2016. A HEADCAP AND WAVE WASHERS CAME OFF FROM AN NSK HANDPIECE, Z95L (SERIAL NO.: (B)(4)) AND DROPPED IN A PATIENT'S MOUTH. THE PATIENT WAS NOT INJURED BY THE DETACHMENT OF THE PARTS.

    Additional Manufacturer Narrative · 1

    UPON RECEIVING THE DEVICE INVOLVED IN THE MDR EVENT FROM A DISTRIBUTOR, NAKANISHI CONDUCTED A FAILURE ANALYSIS OF THE RETURNED DEVICE [C161014-10-1]. THESE ACTIVITIES ARE DESCRIBED IN MORE DETAIL BELOW. METHODOLOGY USED: A) NAKANISHI EXAMINED THE DEVICE HISTORY RECORD AND THE REPAIR HISTORY FOR THE SUBJECT Z95L DEVICE [SERIAL NUMBER (B)(4)]. THERE WERE NO PROBLEMS OBSERVED DURING THE MANUFACTURING OR TESTING NOTED IN THE DHR. THERE WERE ALSO NO REPAIR HISTORY RECORDS SINCE THE DEVICE WAS SHIPPED. B) NAKANISHI CONDUCTED A VISUAL INSPECTION OF THE RETURNED DEVICE. OTHER THAN WASHER AND RETAINER MISSING FROM THE HANDPIECE WHEN THE DEVICE WAS RETURNED, THERE WERE NO VISIBLE ABNORMALITIES, SUCH AS CRACKS, DENTS OR DEFORMATION, ON THE OUTSIDE OF THE HANDPIECE. NAKANISHI ALSO OBSERVED NO ABRASIONS, DETERIORATION OR DIMENSIONAL ABNORMALITY OF THE HEADCAP/HEAD THREAD IN THE VISUAL INSPECTION. C) NAKANISHI OBSERVED WHETHER OR NOT THE HEADCAP OF THE RETURNED HANDPIECE (WITH A NEW WASHER AND RETAINER ATTACHED) WOULD LOOSEN UNDER THE FOLLOWING CONDITIONS. - TIGHTENING TORQUE: 50N?ECM/45N?ECM/35N?ECM/30N?ECM/25N?ECM/20N?ECM/15N?ECM/10N?ECM/5N?ECM - BUR: TEST BUR (DIA.:1.598MM, LENGTH:19.01MM)/2 CARBIDE BURS (DIA.:1.594MM, LENGTH:19.40MM & DIA.:1.594MM, LENGTH:19.42MM)/DIAMOND BUR (DIA.:1.592MM, LENGTH:19.18MM) - MOTOR ROTATION SPEED: TEST BUR (40,000RPM)/CARBIDE BUR (40,000RPM)/DIAMOND BUR (16,000RPM) (NOTE) NAKANISHI USED A SIMILAR DIAMOND BUR PRODUCED BY KOMET IN THE EVALUATION. - LOAD: UNDER NO-LOAD AND UNDER LOAD (LINE ENGRAVING OF PHOSPHOR BRONZE/MELAMINE PLATE) - EVALUATION PERIOD: 3 MINUTES FOR EACH EVALUATION UNDER NO-LOAD AND LOAD NAKANISHI DREW A LINE ON THE HEADCAP AND HEAD AND OBSERVED FOR OCCURRENCE OF MISALIGNMENT. THERE WAS NO HEADCAP LOOSENING OBSERVED UNDER ANY CONDITIONS DESCRIBED ABOVE IN THE EVALUATION. CONCLUSIONS REACHED BASED ON THE INVESTIGATION AND ANALYSIS RESULTS: 1) ALTHOUGH NAKANISHI COULD NOT REPLICATE THE REPORTED EVENT, NAKANISHI CONSIDERS THE POSSIBILITY, FROM SIMILAR PHENOMENON NSK HAS EXPERIENCE IN THE PAST, THAT THE COMBINATION OF A REDUCTION IN HEADCAP TIGHTENING FORCE WITH ABNORMAL VIBRATION (E.G. BUR RUNOUT, CUTTING UNDER HIGH LOAD, ETC.) COULD RESULT IN THE REPORTED HEADCAP LOOSENING/COMING OFF. 2) FAILURE TO CHECK THE HEADCAP TIGHTENESS BEFORE EACH USE AS INSTRUCTED IN THE OPERATION MANUAL, CONTRIBUTES TO THE HEADCAP LOOSENING/COMING OFF WHEN COMBINED WITH ABNORMAL VIBRATION. 3) IN ORDER TO PREVENT A RECURRENCE OF THE HEADCAP LOOSENING/COMING OFF, NAKANISHI TOOK THE FOLLOWING ACTIONS: 3.1) NAKANISHI REVIEWED THE OPERATION MANUAL AND RECONFIRMED CLARITY AND UNDERSTANDABILITY OF THE INSTRUCTIONS. 3.2) NAKANISHI REPORTED THE ABOVE EVALUATION RESULTS TO NSK AMERICA AND DIRECTED NSK AMERICA TO REMIND THE USER OF THE IMPORTANCE OF FOLLOWING INSTRUCTIONS IN THE OPERATION MANUAL.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    722588 NSK HANDPIECE, CONTRA- AND RIGHT-ANGLE ATTACHMENT, DENTAL EGS NAKANISHI INC. Z95L

    Patients

    Seq Age Sex Outcome Treatment
    1 Other