BEUDAMED
    FDA Adverse Event Injury Summary report: N

    NSK

    MDR report key: 19068370 · Received April 8, 2024

    Report

    Report Number
    9611253-2024-00019
    Event Type
    Injury
    Date Received
    April 8, 2024
    Date of Event
    March 7, 2024
    Report Date
    August 22, 2024
    Manufacturer
    NAKANISHI INC.
    Product Code
    KMW
    PMA / PMN Number
    K171155
    Removal / Correction Number
    9611253-060818-001-R
    Adverse Event
    Yes
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    GA, US
    Reporter Occupation
    DENTIST
    Health Professional
    Yes

    Narratives

    Additional Manufacturer Narrative · 0

    THE SAME ADVERSE EVENT IN THIS REPORT HAS BEEN REPORTED TO THE FDA SEPARATELY BY THE DISTRIBUTOR, NSK AMERICA CORPORATION, UNDER REPORT NUMBER (B)(4). THE DENTIST REFUSED TO PROVIDE ANY INFORMATION ABOUT THE PATIENT'S ETHNICITY AND RACE.

    Additional Manufacturer Narrative · 0

    UPON RECEIVING THE DEVICE INVOLVED IN THE MDR EVENT FROM THE DISTRIBUTOR, NAKANISHI CONDUCTED A FAILURE ANALYSIS OF THE RETURNED DEVICE [REPORT NO. C240319-01]. THESE ACTIVITIES ARE DESCRIBED IN MORE DETAIL BELOW. METHODOLOGY USED: A) NAKANISHI EXAMINED THE DEVICE HISTORY RECORD AND THE REPAIR HISTORY FOR THE SUBJECT SGS-E2S DEVICE [B2310156]. 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. B) NAKANISHI CONNECTED THE HANDPIECE TO THE MOTOR AND TRIED TO ROTATE THE MOTOR. HOWEVER, THE HANDPIECE WAS LOCKED, AND THE MOTOR DID NOT ROTATE AT ALL. THEREFORE, NAKANISHI WAS NOT ABLE TO CONDUCT TEMPERATURE TESTING OF THE DEVICE. IDENTIFICATION OF THE SPECIFIC FAILURE MODE(S) AND/OR MECHANISM(S) OF THE ASSOCIATED DEVICE COMPONENTS WAS CONDUCTED AS FOLLOWS: A) NAKANISHI DISASSEMBLED THE HANDPIECE AND PERFORMED A VISUAL INSPECTION OF THE INTERNAL PARTS. NAKANISHI OBSERVED THAT THE BEARING WAS SOILED, DISCOLORED, AND BROKEN. B) NAKANISHI TOOK PHOTOGRAPHS OF ALL THE DISASSEMBLED PARTS AND KEPT THEM IN THE INVESTIGATION REPORT NO. (B)(4). CONCLUSIONS REACHED BASED ON THE INVESTIGATION AND ANALYSIS RESULTS: A) NAKANISHI COULD NOT REPLICATE THE TEMPERATURE INCREASE FROM THE EVENT, BUT BASED ON THE FINDINGS IN THE VISUAL INSPECTION, NAKANISHI IDENTIFIED THAT THE CAUSE OF THE HANDPIECE OVERHEATING WAS ABNORMAL RESISTANCE DURING ROTATION DUE TO THE BROKEN BEARING. B) NAKANISHI CONSIDERS THE POSSIBILITY FROM MANY YEARS OF EXPERIENCE THAT THE CAUSE OF THE BROKEN BEARING WAS THE INGRESS OF UNDESIRABLE MATERIALS INTO THE BEARING, LEADING TO ABRASION. C) A LACK OF MAINTENANCE CAUSED THE ACCUMULATION OF DEBRIS ON THE INTERNAL PARTS, WHICH CONTRIBUTED TO THE HANDPIECE OVERHEATING. D) IN ORDER TO PREVENT A RECURRENCE OF THE HANDPIECE OVERHEATING, NAKANISHI TOOK THE FOLLOWING ACTIONS: D.1) NAKANISHI REVIEWED THE OPERATION MANUAL AND RECONFIRMED THE CLARITY AND UNDERSTANDABILITY OF THE INSTRUCTIONS. D.2) NAKANISHI REPORTED THE ABOVE EVALUATION RESULTS TO THE DISTRIBUTOR AND DIRECTED THE DISTRIBUTOR TO REMIND THE USER OF THE IMPORTANCE OF MAINTENANCE, AS INSTRUCTED IN THE OPERATION MANUAL.

    Description of Event or Problem · 0

    ON MARCH 19, 2024, NAKANISHI BECAME AWARE OF A HANDPIECE OVERHEATING THROUGH A COMPLAINT INPUT INTO THE COMPLAINT DATABASE BY A DISTRIBUTOR (NSK AMERICA). DETAILS ARE AS FOLLOWS: - THE EVENT OCCURRED ON MARCH 7, 2024. - THE DENTIST WAS CUTTING A WISDOM TOOTH ON A PATIENT USING THE SGS-E2S HANDPIECE (SERIAL NO. (B)(6)) - DURING THE PROCEDURE, THE ATTACHMENT LOCKED UP AND OVERHEATED, AND THE PATIENT RECEIVED A BURN INJURY TO THEIR TONGUE. - NO MEDICAL TREATMENT WAS REQUIRED AT THE TIME OF THE INCIDENT. - THE PATIENT HAS NOT HAD A FOLLOW-UP VISIT WITH THE DENTIST AT THIS TIME AND THE DENTIST HAS NOT RECEIVED ANY REPORT OF COMPLICATIONS OR THE NEED FOR FURTHER MEDICAL TREATMENT FROM THE PATIENT AS A RESULT OF THE INJURY.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    456323 NSK HANDPIECE, ROTARY BONE CUTTING KMW NAKANISHI INC. SGS-E2S

    Patients

    Seq Age Sex Outcome Treatment
    1 20 YR Male Other