NSK
Report
- Report Number
- 9611253-2021-00050
- Event Type
- Malfunction
- Date Received
- August 23, 2021
- Date of Event
- August 2, 2021
- Report Date
- September 22, 2021
- Manufacturer
- NAKANISHI INC.
- Product Code
- ELC
- PMA / PMN Number
- K113530
- Product Problem
- Yes
- Report Source
- Manufacturer report
- Reporter Location
- JA
- Reporter Occupation
- 003
Narratives
ON SEPTEMBER 6, 2021, NAKANISHI RECEIVED ADDITIONAL INFORMATION ABOUT THE EVENT. THE PROCEDURE THE DENTIST WAS PERFORMING AT THE TIME OF THE EVENT WAS AN IMPLANT MAINTENANCE PROCEDURE. THE DENTIST CHECKED THE CONNECTION BETWEEN THE TIP AND TIP HOLDER BY PULLING THEM PRIOR TO USE. THE PATIENT WAS NOT UNDER ANESTHESIA. NO INJURY WAS CAUSED TO THE PATIENT IN THE EVENT. UPON RECEIVING THE DEVICE INVOLVED IN THE MDR EVENT, NAKANISHI CONDUCTED A FAILURE ANALYSIS OF THE RETURNED DEVICE [REPORT NO. C210802-01]. THESE ACTIVITIES ARE DESCRIBED IN MORE DETAIL BELOW. METHODOLOGY USED: A) NAKANISHI EXAMINED THE DEVICE HISTORY RECORD AND THE REPAIR HISTORY FOR THE SUBJECT V10 DEVICE [LOT NO. 0KX]. 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 SET THE RETURNED TIP AND TIP HOLDER IN A COMPANY-OWNED HANDPIECE CONNECTED TO A COMPANY-OWNED UNIT AND ACTIVATED THE TIP AT MAXIMUM POWER TO OBSERVE WHETHER OR NOT THE REPORTED EVENT COULD BE REPLICATED. NAKANISHI OBSERVED NEITHER TIP SEPARATION FROM THE TIP HOLDER NOR AN ABNORMAL CONNECTION BETWEEN THE TIP AND TIP HOLDER DURING THE OPERATION TEST. C) NAKANISHI DISASSEMBLED THE TIP HOLDER AND PERFORMED A VISUAL INSPECTION OF THE INTERNAL PARTS. NAKANISHI DID NOT OBSERVE ANY ABNORMALITY, SUCH AS SCRATCHES, DEFORMATION, OR ABRASION. THE INNER DIAMETER OF THE TIP HOLDER WHEN INSERTING A TIP ALSO MET COMPANY CRITERIA. THEN, NAKANISHI PERFORMED A VISUAL INSPECTION OF THE V-P10 TIP. THE TIP HAD NO ABNORMALITIES, SUCH AS ABRASION OF THE WORKING PART OR SHAFT, AND THE DIAMETER OF THE SHAFT WAS WITHIN THE DEVICE SPECIFICATION. D) NAKANISHI TOOK PHOTOGRAPHS OF ALL THE DISASSEMBLED PARTS AND KEPT THEM IN INVESTIGATION REPORT NO. C210802-01. CONCLUSIONS REACHED BASED ON THE INVESTIGATION AND ANALYSIS RESULTS: A) NAKANISHI COULD NOT IDENTIFY THE EXACT CAUSE OF THE TIP SEPARATION FROM THE RETURNED DEVICE BECAUSE NAKANISHI WAS NOT ABLE TO REPLICATE THE REPORTED EVENT AND DID NOT OBSERVE ANY ABNORMALITIES IN THE VISUAL INSPECTION. B) NAKANISHI DID NOT IDENTIFY THE CAUSE, BUT BASED ON NO ABNORMALITIES OBSERVED IN THE VISUAL INSPECTION, AS WELL AS MANY YEARS OF EXPERIENCE, NAKANISHI CONSIDERS THE POSSIBILITY THAT THE CAUSE OF THE TIP SEPARATION IS THAT THE TIP WAS NOT FIRMLY TIGHTENED IN THE TIP HOLDER. C) MISUSE BY THE USER LED TO LOOSE TIGHTENING OF THE TIP, WHICH CONTRIBUTED TO THE BUR SEPARATION. D) IN ORDER TO PREVENT A RECURRENCE OF THE TIP SEPARATION, 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 DENTIST, AND REMINDED THE DENTIST OF THE IMPORTANCE OF USING AND CHECKING THE DEVICE PRIOR TO USE TO PREVENT THE BUR SEPARATION, AS INSTRUCTED IN THE OPERATION MANUAL.
THE DENTIST REFUSED TO PROVIDE ANY INFORMATION ABOUT THE PATIENT.
ON AUGUST 2, 2021, NAKANISHI RECEIVED A PHONE CALL FROM A DISTRIBUTOR ABOUT A MALFUNCTION OF AN NSK PRODUCT. DETAILS ARE AS FOLLOWS. THE EVENT OCCURRED ON (B)(6) 2021. THE DENTIST WAS PERFORMING A DENTAL PROCEDURE ON A PATIENT USING A TIP CONNECTED TO THE V10 TIP HOLDER (LOT NO. 0KX). DURING THE PROCEDURE, THE TIP SUDDENLY SEPARATED FROM THE TIP HOLDER AND FELL INTO THE PATIENT'S MOUTH.
Devices
| Seq | Brand | Generic | Product Code | Manufacturer | Model | Lot | UDI-DI |
|---|---|---|---|---|---|---|---|
| 1254204 | NSK | SCALER, ULTRASONIC | ELC | NAKANISHI INC. | V10 | 0KX |
Patients
| Seq | Age | Sex | Outcome | Treatment |
|---|---|---|---|---|
| 1 | Other |