MAUDE Adverse Event Report: NAKANISHI INC. NSK; HANDPIECE, CONTRA- AND RIGHT-ANGLE ATTACHMENT, DENTAL

Model Number X85L

Device Problems Use of Device Problem (1670); Device Handling Problem (3265)

Patient Problems Injury (2348); Patient Problem/Medical Problem (2688)

Event Date 02/19/2020

Event Type  Injury  

Manufacturer Narrative

The dentist provided the patient's nationality only, refusing to disclose other information about the patient.Upon receiving the device involved in the mdr event from the dealer, 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 x85l device [serial no.(b)(4).There were no problems observed during the manufacturing or testing noted in the dhr.The repair history showed 2 service records since the device was shipped.The repair details are as follows: on (b)(6) 2013: the cartridge, drive shaft, and dog clutch were replaced.On (b)(6) 2013: no problems were observed with the device in the repair work.The device was returned to the customer without being repaired.With respect to the repairs in the above list, the service records indicate that nakanishi performed all of the necessary operation checks, and confirmed that all of the criteria were met.Nakanishi conducted a visual inspection of the returned device.There were no visible abnormalities, such as deformation or dents, on the outside of the push button.There was also no screw loose of the headcap.Nakanishi activated the handpiece to perform a simple movement test.Nakanishi observed abnormal noise and a decrease in retaining force of the chuck.However, no handpiece overheating was confirmed in the test.Nakanishi then disassembled the handpiece and performed a visual inspection of the internal parts.Nakanishi observed the following phenomena: there was an evidence of contact between the push button and the cartridge.There were debris and discoloration on the other parts.Nakanishi took photographs of all of the disassembled parts and kept them in investigation report #(b)(4).Conclusions reached based on the investigation and analysis results: nakanishi identified that the cause of the patient's injury, based on what nakanishi observed in the visual inspection, was the patient's buccal mucous membrane being caught between the button and the cap when the push button was depressed.Misuse by the user led to the contact between the headcap and the cartridge, which contributed to the reported injury.In order to prevent a recurrence of the patient's injury, nakanishi took the following actions: nakanishi reviewed the operation manual and reconfirmed clarity and understandability of the instructions.Nakanishi will report the above evaluation results to the dentist, and remind the dentist of the importance of using the device as instructed in the operation manual.

Event Description

On (b)(6) 2020, an nsk x85l handpiece was returned from a dealer to nakanishi for repair.There was a note with the device stating that the device had caused an injury to a patient.Upon receipt of the information, nakanishi made a phone call to the dentist for further information about the event.The details nakanishi obtained from the communication are as follows: the event occurred on (b)(6) 2020.The dentist was carrying out a preparation for #7 and #8 of the patient's lower jaw using the handpiece x85l (serial no.(b)(4).The patient was under anesthesia.During the procedure, the dentist found bleeding from a 2-3 millimeters injury on the mucosa of the patient's cheek.The dentist determined that no medical attention was required for the injury.According to the dentist, there were no abnormalities observed in the device prior to use.

• Brand Name: NSK
• Type of Device: HANDPIECE, CONTRA- AND RIGHT-ANGLE ATTACHMENT, DENTAL
• Manufacturer (Section D): NAKANISHI INC.; 700 shimohinata; kanuma-shi, tochigi-ken 322-8 666; JA 322-8666
• Manufacturer (Section G): NAKANISHI INC.; 700 shimohinata; kanuma-shi, tochigi-ken 322-8 666; JA 322-8666
• Manufacturer Contact: kenneth block ; 800 e campbell rd.; suite 202; richardson, tx ; 4809554
• MDR Report Key: 9936956
• MDR Text Key: 194140479
• Report Number: 9611253-2020-00014
• Device Sequence Number: 1
• Product Code: EGS
• Combination Product (y/n): N
• Reporter Country Code: JA
• PMA/PMN Number: K972569
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: foreign,other
• Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial
• Report Date: 04/08/2020

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: X85L
• Device Catalogue Number: C604
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 03/21/2020
• Initial Date Manufacturer Received: 03/21/2020
• Initial Date FDA Received: 04/08/2020
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 03/31/2008
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Reuse
• Patient Sequence Number: 1
• Patient Outcome(s): Other