BEUDAMED
    FDA Adverse Event Injury Summary report: N

    NSK X95

    MDR report key: 4805670 · Received May 26, 2015

    Report

    Report Number
    9611253-2015-00026
    Event Type
    Injury
    Date Received
    May 26, 2015
    Date of Event
    November 21, 2013
    Report Date
    May 19, 2015
    Manufacturer
    NAKANISHI, INC.
    Product Code
    EGS
    PMA / PMN Number
    K972563
    Adverse Event
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    JA
    Reporter Occupation
    SERVICE PERSONNEL

    Narratives

    Additional Manufacturer Narrative · 1

    UPON RECEIPT OF THE DEVICE INVOLVED IN THE MDR EVENT, NAKANISHI CONDUCTED A FAILURE ANALYSIS OF THE RETURNED DEVICE THAT INCLUDED MEASUREMENT OF THE TEMPERATURE OF THE OPERATING (C131129-02-1). THESE ACTIVITIES ARE DESCRIBED IN MORE DETAIL BELOW: METHODOLOGY USED: NAKANISHI EXAMINED THE DEVICE HISTORY RECORD FOR THE SUBJECT X95 DEVICE (SERIAL NUMBER (B)(4)). THERE WERE NO PROBLEMS OBSERVED DURING THE MANUFACTURING OR TESTING NOTED IN THE DHR. NAKANISHI CONDUCTED A VISUAL INSPECTION OF THE RETURNED DEVICE AND PERFORMED A SIMPLE MOVEMENT TEST. THERE WERE NO VISIBLE ABNORMALITIES, SUCH AS CRACKS OR DENTS, ON THE OUTSIDE OF THE HANDPIECE. THE DEVICE WAS CONFIGURED FOR TEMPERATURE TESTING IN THE EXACT STATE IN WHICH IT WAS RETURNED. SPECIFICALLY, NO LUBRICATION OR CLEANING WAS PERFORMED ON THE RETURNED DEVICE BEFORE THIS FIRST TEST IN ORDER TO CHARACTERIZE THE DEVICE UNDER CONDITIONS THAT WOULD DUPLICATE THE USE SITUATION AT THE TIME OF EVENT. TEMPERATURE SENSORS WERE FIRST ATTACHED TO THE EXTERIOR OF THE DEVICE AT TEST POINT (E.G., MOST PROXIMAL TO THE PATIENT AND ALONG POINTS FARTHER TOWARD THE DISTAL END OF THE DEVICE). THE TEST SETUP WAS PREPARED TO TAKE TEMPERATURE MEASUREMENTS AT ALL POINTS SIMULTANEOUSLY, INCLUDING A REFERENCE MEASUREMENT AT AMBIENT ROOM TEMPERATURE. WITH WATER AND COOLANT AIR: NAKANISHI ATTACHED A THERMOCOUPLE (SENSOR TO MEASURE A TEMPERATURE) TO EACH OF THE TESTING POINTS FOR THE HANDPIECE TO MEASURE THE EXOTHERMIC SITUATION WITH WATER SPRAY AND COOLANT AIR. NAKANISHI MEASURED THE TEMPERATURE RISE OF THE RETURNED HANDPIECE SET AT 200,000 RPM (MOTOR REVOLUTION 40,000 RPM. NAKANISHI CONFIRMED THAT ONE OF THE TEST POINTS REACHED 48 DEGREES C WITHIN 50 SECONDS AFTER BEGINNING OF THE MEASUREMENT, THEN THE TEMPERATURE WENT DOWN TO 40 DEGREES C. WITHOUT WATER AND COOLANT AIR: NAKANISHI ATTACHED A THERMOCOUPLE (SENSOR TO MEASURE A TEMPERATURE) TO EACH OF THE TESTING POINTS FOR THE HANDPIECE TO MEASURE THE EXOTHERMIC SITUATION WITHOUT WATER SPRAY AND COOLANT AIR. NAKANISHI MEASURED THE TEMPERATURE RISE OF THE RETURNED HANDPIECE SET AT 200,000 RPM (MOTOR REVOLUTION 40,000 RPM). NAKANISHI CONFIRMED THE TEMPERATURE AT EACH OF THE TEST POINTS AS FOLLOWS AFTER THE BEGINNING OF THE MEASUREMENT; IT ROSE TO 70 DEGREES C SUDDENLY. NAKANISHI DISCONTINUED THE MEASUREMENT IN ORDER TO PRESERVE THE HANDPIECE. IDENTIFICATION OF THE SPECIFIC FAILURE MODE(S) AND/OR MECHANISM(S) AND THE ASSOCIATED DEVICE COMPONENT(S) INVOLVED: NAKANISHI DISASSEMBLED THE HANDPIECE AND PERFORMED A VISUAL INSPECTION OF THE INSIDE PARTS. NAKANISHI DID NOT OBSERVE ANY BROKEN PARTS, BUT OBSERVED SOME DIRT AND INSUFFICIENT OIL THAT MIGHT HAVE CAUSED THE HEAT-UP OF THE SUBJECT HANDPIECE. CONCLUSIONS REACHED BASED ON THE INVESTIGATION AND ANALYSIS RESULTS: THE SUBJECT HANDPIECE WAS HEATED UP BECAUSE OF THE DIRT ON THE CARTRIDGE INSIDE THE HANDPIECE ALONG WITH THE USAGE WITHOUT WATER SPRAY AND COOLANT AIR. INSUFFICIENT MAINTENANCE OF THE HANDPIECE CAUSED DIRT ON THE CARTRIDGE. ADDITIONALLY, THE USER DID NOT USE THE HANDPIECE ACCORDING TO NAKANISHI USER MANUAL. THE COMBINATION OF THESE FACTORS CAUSED THE HEAT-UP OF THE SUBJECT HANDPIECE.

    Description of Event or Problem · 1

    THIS MDR IS BEING REPORTED AT THIS TIME AS PART OF OUR INTERNAL REVIEW OF PAST COMPLAINTS AND SERVICE RECORDS. DUE TO THE INCIDENT BEING IN THE PAST, WE ARE LIMITED IN THE INFORMATION WE CAN OBTAIN FROM THE INITIAL COMPLAINANT. THE FOLLOWING INFORMATION IS FROM THE DISTRIBUTOR TO NAKANISHI INC. (NSK) REGARDING A DEVICE MANUFACTURED BY NSK. EVENT SUMMARY: ON (B)(4) 2013, NSK RECEIVED AN ELECTRIC DENTAL HANDPIECE MODEL X95, SERIAL NUMBER (B)(4) FOR REPAIR FROM A DISTRIBUTOR REPAIR FACILITY. ON THE DISTRIBUTOR'S DOCUMENTATION WAS STATEMENT: PATIENT BURNED WITH THIS HANDPIECE. NAKANISHI DID NOT GET ANY DETAILED INFORMATION. COMPLAINT REVIEW: THERE WERE NO PREVIOUS REPAIRS ON FILE FOR THIS HANDPIECE. INVESTIGATION: THE EVALUATION FINISHED ON 12/09/2013.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    339902 NSK X95 EGS NAKANISHI, INC. X95

    Patients

    Seq Age Sex Outcome Treatment
    1 Other