MAUDE Adverse Event Report: NAKANISHI INC. FORZA M5; HANDPIECE, CONTRA- AND RIGHT-ANGLE ATTACHMENT, DENTAL

Model Number FORZA M5

Device Problems Detachment of Device or Device Component (2907); Device Fell (4014)

Patient Problem No Clinical Signs, Symptoms or Conditions (4582)

Event Date 04/05/2022

Event Type  malfunction  

Manufacturer Narrative

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

Event Description

On (b)(6) 2022, nakanishi received an email from a distributor (brasseler usa) about an adverse event in which an nsk handpiece had been involved.Details are as follows: - the event occurred on (b)(6) 2022.- the dentist was performing a crown preparation on a patient using the forza m5 handpiece (serial no.(b)(4).) - during the procedure, the headcap of the handpiece including the bearings and the cover fell off into the patient's mouth.- the headcap was retrieved, and the patient was not injured.

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)(6)].These activities are described in more detail below.Methodology used: a) nakanishi examined the device history record and the repair history for the subject forza m5 device [(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 disassembled the handpiece and conducted a visual inspection of the internal parts.Nakanishi observed the following: - there were no bearing balls in the cartridge.- the cartridge and the shaft were soiled and abraded.C) nakanishi mounted a new cartridge to the head of the handpiece and cut a melamine plate while rotating the handpiece motor under no load at the maximum speed (200,000min-1) to check whether or not the headcap would loosen.The reported loosening of the headcap was not replicated in the device evaluation.D) nakanishi took photographs of all the disassembled parts and kept them in the investigation report no.(b)(6).Conclusions reached based on the investigation and analysis results: a) although nakanishi could not replicate the reported event, nakanishi considers the possibility from similar event that nsk has experienced in the past, the combination of a strong impact on the device together with cutting vibration could result in the reported headcap loosening/separation.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 headcap loosening/separation, 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 maintenance as instructed in the operation manual.

• Brand Name: FORZA M5
• 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: sean kaufman ; 1800 global parkway; hoffman estates, IL 60192 ; 2245128921
• MDR Report Key: 14482899
• MDR Text Key: 300430350
• Report Number: 9611253-2022-00027
• Device Sequence Number: 1
• Product Code: EGS
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: K182999
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Distributor
• Reporter Occupation: Other
• Type of Report: Initial,Followup
• Report Date: 06/30/2022

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 05/24/2022
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: FORZA M5
• Device Catalogue Number: 5027608RF
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Is the Reporter a Health Professional?: No
• Date Manufacturer Received: 06/14/2022
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 10/17/2019
• 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: 56 YR
• Patient Sex: Male