BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    NSK

    MDR report key: 12791423 · Received November 10, 2021

    Report

    Report Number
    9611253-2021-00063
    Event Type
    Malfunction
    Date Received
    November 10, 2021
    Date of Event
    October 14, 2021
    Report Date
    November 11, 2021
    Manufacturer
    NAKANISHI INC.
    Product Code
    EGS
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    JA
    Reporter Occupation
    003

    Narratives

    Additional Manufacturer Narrative · 0

    THE DENTIST REFUSED TO PROVIDE THE PATIENT'S WEIGHT. THIS EVENT OCCURRED IN (B)(6), BUT SIMILAR PRODUCTS ARE MARKETED IN THE US UNDER K182999. UPON RECEIVING THE DEVICE INVOLVED IN THE MDR EVENT FROM THE DISTRIBUTOR, NAKANISHI CONDUCTED A FAILURE ANALYSIS OF THE RETURNED DEVICE [REPORT NO. (B)(4)]. THESE ACTIVITIES ARE DESCRIBED IN MORE DETAIL BELOW. METHODOLOGY USED: NAKANISHI EXAMINED THE DEVICE HISTORY RECORD AND THE REPAIR HISTORY FOR THE SUBJECT DA-800C5L DEVICE (SERIAL NO. (B)(4)) THERE WERE NO PROBLEMS OBSERVED DURING MANUFACTURING OR TESTING NOTED IN THE DHR. THERE WERE ALSO NO REPAIR HISTORY RECORDS SINCE THE DEVICE WAS SHIPPED. NAKANISHI CONDUCTED A VISUAL INSPECTION OF THE DEVICE AND OBSERVED THE FOLLOWING: THE PUSH BUTTON WAS SEPARATED FROM THE DEVICE. THE FORCE FIT RING IN THE PUSH BUTTON WAS ABRADED. NAKANISHI MEASURED THE SIZE OF THE BUR USED AT THE TIME OF THE EVENT. THE ABNORMAL VALUES NAKANISHI OBTAINED IN THE MEASUREMENT ARE AS FOLLOWS. TOTAL LENGTH: 25.14MM (SPECIFICATION IN OPERATION MANUAL: 19MM). MAXIMUM WORKING DIAMETER: 2.20MM (SPECIFICATION IN OPERATION MANUAL: 2.0MM). NAKANISHI ALSO FOUND SCRATCHES ON THE BUR HOLDING AREA. NAKANISHI TOOK PHOTOGRAPHS OF WHAT NAKANISHI OBSERVED IN THE EVALUATION AND KEPT THEM IN INVESTIGATION REPORT #(B)(4). CONCLUSIONS REACHED BASED ON THE INVESTIGATION AND ANALYSIS RESULTS: NAKANISHI COULD NOT IDENTIFY THE EXACT CAUSE OF THE PUSH BUTTON BREAKAGE. HOWEVER, NAKANISHI CONSIDERS THE POSSIBILITY FROM MANY YEARS OF EXPERIENCE AND BASED ON THE FINDINGS IN THE VISUAL INSPECTION, THAT THE FORCE FIT RING CAME OFF DUE TO A COMBINATION OF STRONG IMPACT ON THE DEVICE AND VIBRATION DURING CUTTING, LEADING TO THE BREAKAGE OF THE PUSH BUTTON. NAKANISHI ALSO CONSIDERS THE POSSIBILITY THAT THE USE OF THE OUT-OF-SPECIFICATION BUR INCREASED THE VIBRATION DURING CUTTING, WHICH COULD BE THE CAUSE OF THE FORCE FIT RING COMING OFF, WHICH LED TO THE BREAKAGE OF THE PUSH BUTTON. MISUSE BY THE USER LED TO THE ABOVE ISSUE, WHICH CONTRIBUTED TO THE REPORTED EVENT. ORDER TO PREVENT A RECURRENCE OF THE PUSH BUTTON BREAKAGE/SEPARATION, NAKANISHI TOOK THE FOLLOWING ACTIONS: NAKANISHI REVIEWED THE OPERATION MANUAL AND RECONFIRMED CLARITY AND UNDERSTANDABILITY OF THE INSTRUCTIONS. NAKANISHI REPORTED THE ABOVE EVALUATION RESULTS TO THE USER AND REMINDED THE USER OF THE IMPORTANCE OF USING THE DEVICE AS INSTRUCTED IN THE OPERATION MANUAL.

    Description of Event or Problem · 0

    ON OCTOBER 20, 2021, NAKANISHI RECEIVED A PHONE CALL FROM AN OEM ABOUT A MALFUNCTION OF AN NSK PRODUCT. DETAILS ARE AS FOLLOWS. THE EVENT OCCURRED ON (B)(6) 2021. THE DENTIST WAS PERFORMING A TOOTH EXTRACTION ON THE PATIENT USING THE DA-800C5L HANDPIECE (SERIAL NO. (B)(4)). THE PATIENT WAS UNDER LOCAL ANESTHESIA. DURING THE PROCEDURE, THE PUSH BUTTON BROKE AND FELL IN THE PATIENT MOUTH. THE PUSH BUTTON WAS RETRIEVED FROM THE PATIENT MOUTH, AND THE PATIENT UNDERWENT AN X-RAY TO BE SAFE. ACCORDING TO THE DENTIST, THERE WERE NO ABNORMALITIES OBSERVED IN THE DEVICE PRIOR TO USE.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    1683737 NSK HANDPIECE, CONTRA- AND RIGHT-ANGLE ATTACHMENT, DENTAL EGS NAKANISHI INC. DA-800C5L

    Patients

    Seq Age Sex Outcome Treatment
    1 18 YR Female Other