MAUDE Adverse Event Report: NAKANISHI INC. NSK; SCALER, ULTRASONIC

Model Number VA2-HP

Device Problems Break (1069); Fracture (1260); Detachment of Device or Device Component (2907)

Patient Problems Foreign Body In Patient (2687); No Clinical Signs, Symptoms or Conditions (4582)

Event Date 03/10/2023

Event Type  malfunction  

Manufacturer Narrative

Nakanishi is still trying to obtain further information about the event, including information about the patient, and a follow up report will be made if more information becomes available.

Event Description

On (b)(6) 2023, nakanishi received an email from a distributor (nsk united kingdom) about a patient's accidental ingestion of an nsk scaler tip.The details are as follows: the event occurred on (b)(6) 2023.The dentist was scaling a patient's lower jaw using the g4 scaler tip (lot no.Unknown) with an nsk handpiece, va2-hp (serial no.(b)(6) ).During the procedure, the scaler tip fell into the patient's mouth, and the dentist immediately asked the patient to sit up and spit out the tip but the patient said "i swallowed the tip.It felt like a tooth".The dentist found that the scaler tip had broken off and said to the patient "people often swallow crowns which are similar size.In an ideal world, you would sieve the faeces to confirm that the tip has passed through ok but you may not be willing to do that.The main thing is that you are absolutely certain that you have not inhaled it." the patient said, "i definitely swallowed it".

Event Description

On (b)(6) 2023, nakanishi received the va2-hp handpiece (serial no.(b)(6) ) and the g4 tip (lot no.Ag6) involved in the event and on (b)(6) nakanishi finished an investigation of the handpiece and the tip and identified the following: - the tip was recovered, and the patient did not swallow the tip and was not injured.- the tip was not broken but the thread of the handpiece for attaching the tip was broken and the tip fell into the patient's mouth.

Manufacturer Narrative

The dentist refused to provide information about the patient's weight.This event occurred in the united kingdom, but similar products are marketed in the us under k113530.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 va2-hp device [(b)(4)].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 the following: - the thread of the returned handpiece for attaching the tip was broken.- the tip returned together with the handpiece was worn down to 2mm.- the broken piece of the thread of the handpiece remained in the tip.C) nakanishi removed the remained broken thread from the tip and conducted a visual inspection of the fractured surfaces of the threads and observed the following: - the fractured surfaces were brittle fracture.- both fractured surfaces were symmetrical.D) nakanishi took photographs of all the parts and kept them in the investigation report no.(b)(4).Conclusions reached based on the investigation and analysis results: a) nakanishi identified from the findings in the visual inspection that the cause of the reported event was breakage of the thread of the returned handpiece.Nakanishi considered the possibilities from the similar event that nsk has experienced in the past that the combination of high-load scaling together with impact caused by drops had damaged the thread of the handpiece, leading to the thread fracture b) misuse by the user led to the above issue, which contributed to the reported event.C) in order to prevent a recurrence of the broken thread of the handpiece , nakanishi took the following actions: c.1) nakanishi reviewed the operation manual and reconfirmed the clarity and understandability of the instructions.C.2) nakanishi will report the above evaluation results to the distributor and directed the distributor to remind the user of the importance of using the device as instructed in the operation manual.

• Brand Name: NSK
• Type of Device: SCALER, ULTRASONIC
• 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: sean kaufman ; 1800 global parkway; hoffman estates, IL 60192 ; 2245128921
• MDR Report Key: 17035483
• MDR Text Key: 316291865
• Report Number: 9611253-2023-00035
• Device Sequence Number: 1
• Product Code: ELC
• Combination Product (y/n): N
• Reporter Country Code: UK
• PMA/PMN Number: K113530
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Foreign,Distributor
• Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial,Followup
• Report Date: 07/28/2023

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: VA2-HP
• Device Catalogue Number: E350050
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Initial Date Manufacturer Received: 05/08/2023
• Initial Date FDA Received: 05/31/2023
• Supplement Dates Manufacturer Received: 07/10/2023
• Supplement Dates FDA Received: 07/27/2023
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 07/19/2016
• 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
• Patient Age: 63 YR
• Patient Sex: Female
• Patient Ethnicity: Non Hispanic
• Patient Race: White