MAUDE Adverse Event Report: NAKANISHI INC. NSK; HANDPIECE, AIR-POWERED, DENTAL

Model Number NL4500

Device Problems Break (1069); Entrapment of Device (1212); Detachment of Device or Device Component (2907)

Patient Problems Choking (2464); Foreign Body In Patient (2687); Cough (4457)

Event Date 02/18/2021

Event Type  Injury  

Manufacturer Narrative

The dentist refused to provide the patient's ethnicity and race.

Event Description

On (b)(6), 2021, nakanishi received an email from a distributor (b)(4) about a patient's accidental ingestion of a dental bur.Details are as follows.The event occurred on (b)(6), 2021.The dentist was performing a lower anterior ridge of a patient with copd and emphysema using an nl4500 handpiece (serial no.(b)(4).The patient was on plavix up until 5 days prior.During the procedure, the dentist was trying to remove 2 root tips with the bur after removing 6 anterior teeth on the mandible.The bur touched the bone and fell out of the chuck of the nl4500 handpiece, and went into the patient's throat.The patient coughed and aspirated the bur, and had difficulty in breathing.The patient underwent an x-ray immediately after on the dmd's recommendation.The bur, about 2 centimeters long, was found to be in the lower right bronchia in the x-ray.The bur was a 557 surgical length carbide bur from a competitor.The patient will need a thoracic surgery to remove the bur.

Manufacturer Narrative

On april 28, 2021, nakanishi received additional information about the event from the distributor.- the cardiothoracic surgeon was able to surgically remove the entire bur from the patient's bronchi and the patient is healing nicely.- the office manager acknowledged that the user (dental assistant or dentist) most likely did not seat the bur entirely into the handpiece, therefore it came out and was aspirated.

Manufacturer Narrative

Upon receiving the device involved in the mdr event from the distributor, nakanishi conducted a failure analysis of the returned device [report no.(b)(4)].These activities are described in more detail below.Methodology used: a) nakanishi examined the device history record and the repair history for the subject nl4500 device [serial no.(b)(6)].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 conducted a visual inspection of the returned device and observed that the tip of the bur attached to the handpiece was broken.C) nakanishi measured the bur retention force and observed a value within device specifications.D) nakanishi rotated the device to observe whether or not the bur would rotate off-center.No abnormal rotation was confirmed in the evaluation.Conclusions reached based on the investigation and analysis results: a) despite the fact that nakanishi did not observe a decrease in bur retention force nor off-center rotation leading to the reported bur removal, nakanishi identified from the visual inspection that the cause of the event was that the bur had been broken during the rotation and fallen in the patient's mouth.B) in spite of the fact that nakanishi could not identify the cause, nakanishi took the following actions to be safe: b.1) nakanishi reviewed the operation manual and reconfirmed the clarity and understandability of the instructions.B.2) nakanishi reported the above evaluation results to brasseler usa and directed brasseler usa to remind the user of the importance of using the device as instructed in the operation manual.

• Brand Name: NSK
• Type of Device: HANDPIECE, AIR-POWERED, DENTAL
• Manufacturer (Section D): NAKANISHI INC.; 700 shimohinata; kanuma-shi, tochigi-ken 322-8 666; JA 322-8666
• MDR Report Key: 11521324
• MDR Text Key: 254840440
• Report Number: 9611253-2021-00017
• Device Sequence Number: 1
• Product Code: EFB
• Combination Product (y/n): N
• PMA/PMN Number: K112024
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: distributor
• Type of Report: Initial,Followup,Followup
• Report Date: 05/25/2021

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 03/18/2021
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: NL4500
• Device Catalogue Number: 5025051U0
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 04/02/2021
• Date Manufacturer Received: 04/28/2021
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Outcome(s): Other
• Patient Age: 85 YR
• Patient Weight: 70