BEUDAMED
    FDA Adverse Event Injury Summary report: N

    NSK

    MDR report key: 4772365 · Received May 12, 2015

    Report

    Report Number
    9611253-2015-00030
    Event Type
    Injury
    Date Received
    May 12, 2015
    Report Date
    May 7, 2015
    Manufacturer
    NAKANISHI, INC.
    Product Code
    EGS
    Adverse Event
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    JA
    Reporter Occupation
    OTHER

    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 DEVICE. THESE ACTIVITIES ARE DESCRIBED IN MORE DETAIL BELOW. METHODOLOGY USED: NAKANISHI MEASURED THE TEMPERATURE RISE OF THE RETURNED HANDPIECE AS FOLLOWS: A. TEMPERATURE SENSORS WERE FIRST ATTACHED TO THE EXTERIOR OF THE DEVICE AT VARIOUS TEST POINTS (E.G. MOST PROXIMAL TO THE PATIENT AND ALONG POINTS FURTHER 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. B. NAKANISHI ATTACHED A THERMOCOUPLE (SENSOR TO MEASURE A TEMPERATURE) TO EACH OF THE TESTING POINTS. NAKANISHI ROTATED THE HANDPIECE AND MEASURED THE EXOTHERMIC SITUATION. C. NAKANISHI CONFIRMED A MAXIMUM TEMPERATURE OF 54.9 DEGREES C, WHICH IS OUTSIDE NAKANISHI SPECIFICATION. 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 OBSERVED DAMAGES ON THE INNER SIDE OF A PUSH BUTTON AND ROTATING SHAFT OF A CARTRIDGE. CONCLUSIONS REACHED BASED ON THE INVESTIGATION AND ANALYSIS RESULTS: FROM THE OBSERVATION OF THE DAMAGED INNER PARTS NAKANISHI BELIEVE THAT THERE WAS A CONTACT BETWEEN THE PUSH BUTTON AND ROTATING SHAFT DURING OPERATION. THERE IS A POSSIBILITY THAT THE PUSH BUTTON WAS ACCIDENTLY PRESSED BY THE OPERATOR. CONTACT OF THE INNER PARTS CAUSE ABNORMAL ROTATION RESISTANCE THAT CONTRIBUTES TO THE HANDPIECE OVERHEATING. IN ORDER TO PREVENT THE REOCCURRENCE, NAKANISHI REMINDED THE OPERATOR OF THE DESCRIPTION INCLUDED IN THE USER MANUAL. THIS EVENT OCCURRED IN (B)(4), BUT THE SIMILAR PRODUCTS ARE MARKETED IN THE US UNDER K972569.

    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 THAT WE CAN OBTAIN FROM THE INITIAL COMPLAINANT. NAKANISHI RECEIVED THE INFORMATION THAT A PATIENT WAS BURN ON THE MOUTH CORNER DUE TO OVERHEATING OF THE HANDPIECE. THE DENTIST PRESCRIBED AN ANTIBIOTIC TO THE PATIENT. THIS EVENT OCCURED IN (B)(4), BUT THE SIMILAR PRODUCTS ARE MARKETED IN THE USE UNDER K972569.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    311017 NSK EGS NAKANISHI, INC. IS10

    Patients

    Seq Age Sex Outcome Treatment
    1 Other